Exploration and exploitation of homologous series of bis(acrylamido)alkanes containing pyridyl and phenyl groups: β-sheet versus two-dimensional layers in solid-state photochemical [2 + 2] reactions

Garai, M.; Biradha, K.

doi:10.1107/S2052252515009987

research papers

IUCrJ

Volume 2| Part 5| September 2015| Pages 523-533

ISSN: 2052-2525

https://doi.org/10.1107/S2052252515009987

CHEMISTRY | CRYSTENG

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Exploration and exploitation of homologous series of bis(acrylamido)alkanes containing pyridyl and phenyl groups: β-sheet versus two-dimensional layers in solid-state photochemical [2 + 2] reactions

Mousumi Garai ^a and Kumar Biradha ^a ^*

^aDepartment of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India
^*Correspondence e-mail: kbiradha@yahoo.com

Edited by C.-Y. Su, Sun Yat-Sen University, China (Received 25 March 2015; accepted 22 May 2015; online 31 July 2015)

The homologous series of phenyl and pyridyl substituted bis(acrylamido)alkanes have been synthesized with the aim of systematic analysis of their crystal structures and their solid-state [2 + 2] reactivities. The changes in the crystal structures with respect to a small change in the molecular structure, that is by varying alkyl spacers between acrylamides and/or by varying the end groups (phenyl, 2-pyridyl, 3-pyridyl, 4-pyridyl) on the C-terminal of the amide, were analyzed in terms of hydrogen-bonding interference (N—H⋯N_py versus N—H⋯O=C) and network geometries. In this series, a greater tendency towards the formation of N—H⋯O hydrogen bonds (β-sheets and two-dimensional networks) over N—H⋯N hydrogen bonds was observed. Among all the structures seven structures were found to have the required alignments of double bonds for the [2 + 2] reaction such that the formations of single dimer, double dimer and polymer are facilitated. However, only four structures were found to exhibit such a solid-state [2 + 2] reaction to form a single dimer and polymers. The two-dimensional hydrogen-bonding layer via N—H⋯O hydrogen bonds was found to promote solid-state [2 + 2] photo-polymerization in a single-crystal-to-single-crystal manner. Such two-dimensional layers were encountered only when the spacer between acryl amide moieties is butyl. Only four out of the 16 derivatives were found to form hydrates, two each from 2-pyridyl and 4-pyridyl derivatives. The water molecules in these structures govern the hydrogen-bonding networks by the formation of an octameric water cluster and one-dimensional zigzag water chains. The trends in the melting points and densities were also analyzed.

Keywords: homologous series; hydrogen bonds; solid-state [2 + 2] reaction; organic polymer.

CCDC references: 1055532; 1055533; 1055534; 1055535; 1055536; 1055537; 1055538; 1055539; 1055540; 1055541; 1055542

1. Introduction

The systematic exploration of solid-state ensembles of organic molecules containing functional groups which possess similar interactive capabilities albeit minor variations laid the foundation for the gigantic rise of the field of crystal engineering (Schmidt, 1971 ; Desiraju, 1989 ; Lehn, 1995 ; Whitesides et al., 1995 ; Aakeröy et al., 2001 ; Moulton & Zaworotko, 2001 ; Zaworotko, 2001 ; Desiraju, 2002 ; Biradha, 2003 ; Vangala et al., 2005 ; Rajput et al., 2007 a; Mukherjee & Biradha, 2011b ). The comparison between various halogen derivatives, either by changing the halogen atoms or by changing their position on the aromatic ring is one of the finest examples of such systematic explorations (Bent, 1968 ; Legon, 1999 ; Metrangolo & Resnati, 2001 ; Metrangolo et al., 2005 , 2008 ; Marras et al., 2006 ; Shirman et al., 2008 ; Samai & Biradha, 2009 ). On the other hand, the similarities or anomalies in the properties of homologues series of n-alkanes and α,ω-substituted dithiols, diols, diamines and diacids are well understood from their crystal structures (Hicks & Nodwell, 2000 ; Xu et al., 2002 ; Vishweshwar et al., 2003 ; Gibson et al., 2003 ; Lee et al., 2007 ). Apart from these very few homologous series, in particular molecules containing more than one functional group that are capable of hydrogen bonding, are characterized crystallographically. The increase in functional groups and flexibility increases the complexity and decreases the probability of having isostructurality in the series. Further, the isostructurality of homologous series is not an obvious fact as the process of crystallization depends on several factors such as aggregation, size and solvation apart from the structure of a molecule.

In these lines we have previously reported our studies on homologous series of N,N′-bis(pyridinecarboxamido)alkanes (amides) (Sarkar & Biradha, 2006 ) and N,N′-bis(pyridyl)alkanediamides (reverse amides) (Rajput et al., 2007 b) in which amide moieties are separated by alkyl (—(CH₂)_n—) spacers (Fig. 1). From these studies it was evident that both series exhibit an odd–even effect on the nature of the hydrogen bond and their network features (Mukherjee & Biradha, 2011a ). As these classes of compounds contain two each of amide and pyridine moieties, the molecules were assembled through either N—H⋯O or N—H⋯N or both the interactions. The β-sheets or (4,4)-networks, via N—H⋯O or N—H⋯N hydrogen bonds, are the two most common motifs displayed by the derivatives containing an even number of —CH₂— groups. The amide molecules were found to assemble mostly via amide-to-amide recognitions in amides, while pyridine interferences to the amide-to-amide hydrogen bond was found to be more prominent in the case of the reverse amide series, i.e. the N—H⋯N interaction is preferred over the N—H⋯O hydrogen bond. In contrast to the formation of the β-sheets or (4,4)-networks by the even ones, the formation of three-dimensional structures were found to be more frequent in the case of odd ones.

Figure 1
Amides and reverse amides

From these studies it was understood that the hydrogen bonded (4,4)-networks can promote solid-state [2 + 2] reactions (Garai et al., 2013 ) to form polymers containing cyclobutanes and amides in the chain with the phenyl/pyridyl groups as dangling attachments, provided the bis-amide molecules contain double bonds at the terminals. In order to test this hypothesis several derivatives of 1–4 were prepared by changing the spacers between the amide functionalities (Fig. 2). The crystal structures were analyzed in comparison with those of homologues series of amides and reverse amides. Further, the solid-state [2 + 2] reactions were explored wherever possible. It was shown by us earlier that the crystal structures of molecules 1c and 3c containing the butane spacer possess such unique features to form the hydrogen bonded (4,4)-layer which promotes the polymerization reaction as anticipated in a single-crystal-to-single-crystal (SCSC) manner to yield crystalline organic polymers (Garai et al., 2013). Such polymerization reactions are very rare and the only example in the literature is 2,5-distyrylpyrazine reported by Hasegawa et al. (Hasegawa, 1983 ; Hasegawa et al., 1986 ). In this manuscript the following points will be addressed by analyzing homologous series of crystal structures of 1–4: (1) competition between the O atom of the amide and the N atom of pyridine to form hydrogen bonds with the amide N—H group; (2) similarities or differences with previously published bis-amide analogues; (3) formation of the two-dimensional layer versus the β-sheet hydrogen-bond networks (Fig. 3); (4) propensity for the formation of hydrates; (5) trends in their melting points; (6) alignment of double bonds for solid-state [2 + 2] reactions; (7) exploration of their reactivities and characterization of their products wherever possible.

Figure 2
1: R = phenyl; 2: R = 2-pyridyl; 3: R = 3-pyridyl; 4: R = 4-pyridyl, a: X = —HN—NH—, b: X = —HN—(CH₂)₂—NH, c: X = —HN—(CH₂)₄—NH—; d: X = —HN—(CH₂)₆—NH—.

Figure 3
Representation of (a) β-sheet and (b) two-dimensional layers.

2. Experimental

FTIR spectra were recorded with a Perkin–Elmer Instrument Spectrum Rx Serial No. 73713. Powder XRD patterns were recorded with a Bruker AXS-D8-ADVANCE diffractometer (Cu target). ¹H NMR (200/600 MHz) spectra were recorded on a Bruker AC 200/600 MHz spectrometer. The MALDI-TOF experiment was carried out using a Bruker ultrafleXtreme MALDI TOF/TOF mass spectrometer.

2.1. Synthesis of 1a

In a round-bottom flask cinnamic acid (1.21 g, 0.0081 mol) and pyridine (15 ml) were taken and hydrazine hydrate (0.194 ml, 0.004 mol) was added to the reaction mixture and stirred for ∼ 15–20 min. After that triphenyl phosphite (2.25 ml, 0.0086 mol) was added to it and the reaction mixture was refluxed for 7–8 h.

After cooling to room temperature, the pyridine was distilled out to reduce the volume up to 5 ml. For the work up process, EtOH was added and then the solid product was filtered and washed with EtOH. The white solid product was recrystallized from methanol–DMF.

1a. Yield: 78%; m.p.: 280°C. Anal.: calc. for C₁₈H₁₆N₂O₂: C 74.0, H 5.5, N 9.6; found: C 69.49, H 4.79, N 8.59%.

Compounds 1b–1d, 2a–2d and 3a–3d were prepared by following the above procedure, but by using corresponding diamine and cinnamic acid, (E)-3-(pyridin-2-yl)-acrylic acid and (E)-3-(pyridin-3-yl)-acrylic acid, respectively.

1b. Yield: 84%; m.p.: 250°C. Anal.: calc. for C₂₀H₁₈N₂O₂: C 75.4, H 5.7, N 8.8; found: C 64.67, H 4.76, N 7.68%.

1c. Yield: 72%; m.p.: 268°C. Anal.: calc. for C₂₂H₂₄N₂O₂: C 75.83, H 6.94, N 8.04; found: C 75.20, H 6.72, N 7.84%.

2a. Yield: 56%; m.p.: 248°C. Anal.: calc. for C₁₆H₁₄N₄O₂: C 68.6, H 7.5, N 20.0; found: C 68.2, H 6.82, N 19.8%.

2b. Yield: 42%; m.p.: 210°C. Anal.: calc. for C₁₈H₁₈N₄O₆: C 56.0, H 4.7, N 14.5; found: C 55.2, H 4.52, N 13.8%.

2d. Yield: 60%; m.p.: 182°C. Anal.: calc. for C₂₂H₂₆N₄O₄: C 64.4, H 6.4, N 13.7; found: C 63.9, H 5.82, N 12.8%.

3a. Yield: 57.2%; m.p. 272°C. Anal.: calc. for C₁₆H₁₄N₄O₂: C 65.68, H 4.42, N 18.76; found: C 65.30, H 4.79, N 19.04%.

3b. Yield: 78%; m.p.: 235°C. Anal.: calc. for C₁₈H₁₈N₄O₂: C 67.1, H 5.6, N 17.4; found: C 66.43, H 5.62, N 16.52%.

3c. Yield: 60%; m.p.: 249°C. Anal.: calc. for C₂₀H₂₂N₄O₂: C 68.55, H 6.33, N 15.99; found: C 67.74, H 6.63, N 14.96%.

2.2. Synthesis of 4a

In a round-bottom flask (E)-3-(pyridine-4-yl) acrylic acid (0.596 g, 0.000399 mol), pentafluorophenol (0.8 g, 0.00434 mol) and DCC (0.908 g, 0.0044 mol) were taken in 20 ml of dry THF solvent and stirred over 24 h at room temperature, then the solvent was distilled out to collect the solid product. The solid product was recrystallized from pet-ether. The recrystallized ester (1 g, 0.00313 mol) and hydrazine hydrate (0.077 ml, 0.00109 mol) were taken in dry DMF solvent and stirred at room temperature for 24 h. Then the solid product was filtered and recrystallized with MeOH. Yield: 62.8%; m.p. 279°C. Anal.: calc. for C₁₆H₁₄N₄O₂: C 65.30, H 4.79, N 19.04; found: C 64.94, H 4.53, N 18.76%.

Similar procedures were followed for the synthesis of 4b–4d by using the corresponding diamines and pentafluoroester of (E)-3-(pyridine-4-yl) acrylic acid. In these cases, dry THF was used as the solvent.

4b. Yield: 58%; m.p.: 275°C. Anal.: calc. for C₁₈H₁₈N₄O₂: C 67.1, H 5.6, N 17.4; found: C 66.9, H 5.49, N 16.69%.

4c. Yield: 66%; m.p.: 235–238°C. Anal.: calc. for C₂₀H₂₆N₄O₄: C 62.2, H 6.8, N 14.5; found: C 61.49, H 5.59, N 14.19%.

4d. Yield: 58%; m.p.: 175°C. Anal.: calc. for C₂₂H₃₀N₄O₄: C 63.7, H 7.3, N 13.5; found: C 62.79, H 6.49, N 12.46%.

2.3. Crystallographic data and refinement details

All the single-crystal data were collected on a Bruker APEX-II CCD X-ray diffractometer that uses graphite monochromated Mo Kα radiation (λ = 0.71073 Å) at room temperature (293 K) by the hemisphere method. The structures were solved by direct methods and refined by least-squares methods on F² using SHELX97 (Sheldrick, 2015 ). Non-hydrogen atoms were refined anisotropically and hydrogen atoms were fixed at calculated positions and refined using a riding model.

3. Results and discussion

The compounds 1a–1d, 2a–2d and 3a–3d are synthesized by refluxing the corresponding diamines with cinnamic acid, (E)-3-(pyridin-2-yl)-acrylic acid and (E)-3-(pyridin-3-yl)-acrylic acid, respectively, in the presence of triphenyl phosphate in pyridine. The same procedure was found to be incompatible for the syntheses of derivatives of 4. Therefore, compounds 4a–4d are synthesized by reacting the pentafluoroester of (E)-3-(pyridin-4-yl)-acrylic acid with corresponding diamines. Single crystals suitable for X-ray diffraction were obtained by the slow evaporation technique from methanol, ethanol or methanol–DMF, methanol–THF solutions of the corresponding compounds. Despite several trails the single crystals suitable for X-ray diffraction analyses could not be obtained for 2c and 3d. The comparison of X-ray powder diffraction (XRPD) patterns with the related analogues hinted at their probable crystal structures. The crystal structures of all the derivatives have been analyzed in terms of hydrogen-bonding networks and comparisons were made with respect to the related derivatives of amides and reverse amides. Further, these studies revealed that the series of these 16 structures can be categorized as four types: (1) β-sheet via N—H⋯O hydrogen bonds; (2) β-sheet via N—H⋯N hydrogen bonds; (3) two-dimensional layer via N—H⋯O hydrogen bonds; (4) two-dimensional layer via N—H⋯N hydrogen bonds. In the following sections the results will be described based on the spacers as listed in Fig. 2. The photochemical [2 + 2] reactions were carried out on 1c, 2b, 2c, 3a, 3c, 4a and 4c as the structures indicated the possibility of such reactions. The pertinent crystallographic details are given in Table 1 and the hydrogen-bonding parameters are given in Table 2.

Table 1
Crystallographic data and structure refinement parameters for compounds

	1a	1b	1d	2a	2b	2d
Chemical formula	C₁₈H₁₆N₂O₂	C₂₀H₂₀N₂O₂	C₂₄H₂₈N₂O₂	C₁₆ H₁₄N₄O₂	C₁₈H₁₈N₄O₆	C₂₂H₂₆N₄O₄
M_r	292.33	320.38	376.48	294.31	394.43	414.50
T (K)	293	293	293	100	293	293
Crystal system	Monoclinic	Monoclinic	Monoclinic	Monoclinic	Monoclinic	Monoclinic
Space group	C2/c	P2₁/c	P2₁/c	P2₁/n	P2₁/c	P2₁/c
a (Å)	18.451 (9)	17.899 (3)	20.243 (5)	4.7315 (10)	9.3530 (6)	7.6364 (14)
b (Å)	10.540 (5)	4.8544 (9)	4.9756 (14)	9.213 (2)	10.9015 (7)	30.058 (5)
c (Å)	8.157 (4)	9.5259 (16)	20.839 (6)	16.390 (4)	19.9985 (14)	4.8885 (9)
α (°)	90.00	90.00	90.00	90.00	90.00	90.00
β (°)	98.824 (12)	101.847 (4)	99.148 (8)	97.020 (6)	94.547 (2)	95.523 (6)
γ (°)	90.00	90.00	90.00	90.00	90.00	90.00
V (Å³)	1567.6 (13)	810.1 (2)	2072.2 (10)	709.1 (3)	2032.7 (2)	1116.9 (3)
Z	4	2	4	2	4	2
D_x (mg m⁻³)	1.239	1.313	1.207	1.378	1.289	1.233
R₁ [I > 2(σI))]	0.0549	0.00373	0.0785	0.0401	0.0638	0.0714
wR₂ (on F², all data)	0.1930	0.1071	0.2013	0.1319	0.2030	0.1999

	3a	3b	4b	4c	4d
Chemical formula	C₁₆H₁₄N₄O₂	C₁₈H₁₈N₄O₂	C₁₈H₁₈N₄O₂	C₂₀H₂₆N₄O₄	C₂₂H₃₀N₄O₄
M_r	294.31	322.36	322.36	386.45	414.50
T (K)	293	293	293	100	293
Crystal system	Monoclinic	Monoclinic	Monoclinic	Monoclinic	Monoclinic
Space group	P2₁/c	C2/c	P2₁/n	P2₁/c	P2₁/n
a (Å)	10.403 (6)	34.566 (5)	4.7967 (15)	12.78 (2)	7.3720 (7)
b (Å)	7.160 (4)	9.3338 (13)	11.547 (4)	4.681 (9)	4.9035 (4)
c (Å)	19.202 (11)	10.4191 (15)	14.726 (5)	16.21 (3)	31.586 (3)
α (°)	90.00	90.00	90.00	90.00	90.00
β (°)	101.156 (17)	100.401 (4)	96.451 (10)	93.42 (3)	90.197 (3)
γ (°)	90.00	90.00	90.00	90.00	90.00
V (Å³)	1403.1 (14)	3306.3 (8)	810.5 (4)	968 (3)	1141.78 (18)
Z	4	8	2	2	2
D_x (mg m⁻³)	1.393	1.295	1.321	1.326	1.206
R₁ [I > 2(σI)]	0.0430	0.0599	0.0646	0.0853	0.0599
wR₂ (on F², all data)	0.0801	0.2079	0.1403	0.2241	0.2079

Table 2
Geometrical parameters (Å, °) of hydrogen bonds

	Type	H⋯A (Å)	D⋯A (Å)	D—H⋯A (°)
1a	N—H⋯O	1.97	2.823 (3)	173
1a	C—H⋯O	2.51	2.843 (3)	101
1b	N—H⋯O	2.04	2.889 (2)	171
1d	N—H⋯O	2.13	2.974 (4)	166
	N—H⋯O	2.09	2.939 (4)	170
	C—H⋯O	2.53	2.858 (5)	101
2a	N—H⋯O	2.06	2.817	147
	C—H⋯N	2.58	3.442 (6)	155
	C—H⋯O	2.58	3.400 (3)	148
	C—H⋯O	2.54	2.847 (5)	100
2b	N—H⋯O	2.20	3.056 (3)	174
	N—H⋯O	2.23	3.037 (3)	156
	C—H⋯O	2.47	2.809 (3)	101
	C—H⋯O	2.49	3.381 (3)	160
	C—H⋯O	2.56	2.875 (3)	100
	C—H⋯O	2.43	2.767 (3)	100
2d	N—H⋯O	2.11	2.943 (4)	162
	C—H⋯O	2.60	3.443 (6)	152
	C—H⋯O	2.51	2.838 (5)	101
3a	N—H⋯O	2.20	3.032 (3)	163
	N—H⋯O	2.32	3.165 (3)	169
	C—H⋯O	2.46	3.144 (3)	131
	C—H⋯O	2.50	2.839 (3)	101
	C—H⋯O	2.55	3.222 (3)	130
	C—H⋯O	2.50	3.198 (3)	132
	C—H⋯O	2.50	2.841 (3)	102
3b	N—H⋯O	2.06	2.910 (3)	167
	N—H⋯O	1.97	2.809 (3)	166
	C—H⋯O	2.49	2.828 (3)	101
	C—H⋯O	2.52	2.848(3)	101
4b	N—H⋯N	2.15	2.980 (5)	161
	C—H⋯O	2.48	3.219 (6)	137
	C—H⋯O	2.54	2.861 (5)	100
	C—H⋯O	2.45	2.825 (5)	103
4c	O—H⋯O	1.83 (5)	2.763 (7)	153 (3)
	O—H⋯N	2.06 (4)	2.805 (7)	169 (5)
	N—H⋯O	1.97	2.803 (7)	164
	C—H⋯O	2.42	3.112 (8)	131
	C—H⋯O	2.52	3.463 (8)	165
	C—H⋯O	2.45	2.822 (7)	103
4d	N—H⋯O	2.07	2.921 (2)	168
	O—H⋯N	2.02 (3)	2.891 (4)	169.3 (19)
	C—H⋯O	2.53	2.849 (3)	100

3.1. β-sheet and two-dimensional layers with the —HN—NH— spacer

Molecules 1a, 2a, 3a and 4a all crystallize in monoclinic space groups C2/c, P2₁/n, P2₁/c and P2₁/n, respectively. With the exception of 3a, which contains one molecule, all the other three contain half molecules in the asymmetric unit. Interestingly no solvent inclusion was found in all four lattices, making the comparison between these structures more realistic. With the exception of 1a, the hydrazine moieties (C—N—N—C: 164° in 2a and 3a and 180° in 4a) exhibited near co-planar geometry. In 1a the hydrazine moiety resembles that of a simple hydrazine or H₂O₂ with C—N—N—C torsion of 115°. The molecules in 1a (along the c-axis with a repeat distance of 4.07 Å) and 2a (along the a-axis with a repeat distance of 4.73 Å) assemble via N—H⋯O hydrogen bonds to form β-sheets containing ten-membered rings. Although both form β-sheets the differences in both the structures are apparent given the differences in the geometry of the spacer and molecules: non-coplanar in 1a and nearly planar in 2a. In 1a the molecules are aligned in a zigzag manner, while in 2a they are aligned in a plane containing the hydrogen bonds. In 1a the hydrogen bonds [N⋯O, N—H⋯O: 2.823 (3) Å, 173.5°] are more linear than those in 2a (N⋯O, N—H⋯O: 2.817 Å, 147.4°) (Fig. 4). Given these differences the packing of β-sheets also differ significantly: in 1a the sheets have a parallel packing (C—H⋯π and π⋯π interactions), while in 2a they have herringbone packing (C—H⋯N, C—H⋯π and π⋯π interactions) (Fig. S33).

Figure 4
Illustrations for the crystal structures of 1a and 2a: packing diagrams for (a) 1a and (c) 2a; β-sheets in (b) 1a and (d) 2a. Notice the difference in alignment of molecules within the β-sheet between 1a and 2a.

In 3a and 4a the pyridyl groups are found to exhibit interference and form N—H⋯N hydrogen bonds. Although both are nearly planar molecules the hydrogen-bonding patterns and packing are found to differ drastically. In 3a the molecules assemble to form a one-dimensional chain that resembles a β-sheet but via N—H⋯N hydrogen bonds and also the molecules are off-set. These one-dimensional chains pack in a parallel fashion which is somewhat similar to that of 1a (Fig. 5). Whereas in 4a, the molecules assemble to form a herringbone layer via N—H⋯N hydrogen bonds containing rectangular cavities which are filled by the adjacent layers. The layers pack such that the double bonds are aligned for double [2 + 2] reaction (Fig. 6).

Figure 5
Illustrations for the crystal structure of 3a: (a) packing diagram; (b) one-dimensional chain via N—H⋯N hydrogen bonds; (c) off-set packing of 3a; (d) stacking of 3a for single [2 + 2] reaction.

Figure 6
Illustrations for the crystal structure of 4a: (a) a two-dimensional herringbone layer via N—H⋯N hydrogen; (b) packing of layers on top of each other to form infinite stacks. Note that the double bonds are aligned within the stacks to undergo double [2 + 2] reaction.

3.2. β-sheet, two-dimensional layers and water inclusion with —HN—(CH₂)₂—NH— spacer

The molecules 1b and 2b crystallized in space group P2₁/c, while 3b and 4b crystallized in space groups C2/c and P2₁/n, respectively. The asymmetric units of 1b and 4b are constituted by a half unit of the corresponding molecules, while that of 3b is constituted by two half units of 3b. The asymmetric unit of 2b contains one full molecule and four H₂O molecules. The geometries of these molecules were found to be different, although all contain the HN—CH₂—CH₂—NH moiety with anti geometry (N—C—C—N: 180° in 1b, 3b and 4b and 176° in 2b). The interplanar angles between the amide planes are 0° in 1b, 3b and 4b, while it is 61° in 2b. Further, the plane of C=C—C=O creates the following angles with the central N—C—C—N plane: 19° in 1b, 80° and 19° in 2b, 77° and 12° in 3b and 72° in 4b.

In 1b and 3b, the molecules assemble via N—H⋯O hydrogen bonds to form the usual β-sheets along the b-axis. The molecules within the sheet are in-plane in 1b with a repeat distance of 4.85 Å, while they are not in-plane in 3b and contain a repeat distance of 4.65 Å. The sheets pack in a parallel fashion in the case of 1b, while the sheets exhibit some angularity in the packing in 3b (Fig. 7).

Figure 7
Illustrations for the crystal structures of 1b and 3b: packing diagrams for (a) 1b and (b) 3b; β-sheets observed in (c) 1b and (d) 3b. Notice the difference in alignment of molecules within the β-sheet between 1b and 3b.

The crystal structure of 2b is drastically different from all the structures presented here as the crystal lattice contains four water molecules which govern the overall hydrogen-bonding interactions. No amide-to-amide or amide-to-pyridine hydrogen bonding was found in this structure. The water molecules form an octamer via O—H⋯O hydrogen bonds. The octamer contains a flat six-membered ring with the other two water molecules linked at 1,4 positions. These octamers link the molecules of 2b into a three-dimensional network with a plethora of hydrogen-bonding interactions. In the octamer, in terms of hydrogen bonding three types of water molecules exists: (1) four water molecules involved in four hydrogen bonds each, two O—H⋯O with H₂O, one N—H⋯Ow with the amide and one O—H⋯N with the pyridine N-atom; these O atoms exhibit near tetrahedral geometry in terms of hydrogen bonding; (2) two involved in exclusively three Ow—H⋯Ow hydrogen bonds each with water molecules; (3) two involved in one Ow—H⋯Ow and two Ow—H⋯O=C hydrogen bonds each. The second and third categories exhibit nearly planar geometry in terms of hydrogen bonding. In this three-dimensional network, it was found that the double bonds are aligned for a single [2 + 2] reaction (Fig. 8).

Figure 8
Illustrations for the crystal structure of 2b: (a) linking of molecules of 2b into the three-dimensional network by the O—H⋯O and N—H⋯O hydrogen bonds with lattice water molecules; (b) octameric water cluster via O—H⋯O hydrogen bonds; (c) alignment of double bonds of 2b for a single [2 + 2] reaction.

The crystal structure of 4b bears a close resemblance to that of 4a as it forms a similar herringbone layer via N—H⋯N hydrogen bonds. However, here the double bonds are not aligned for the [2 + 2] reaction as the packing of the layers differ due to the presence of the —CH₂—CH₂— spacer. Further, this structure is found to be isostructural with that of the amide analogues with 4-pyridyl substitution and the ethyl spacer.

3.3. N—H⋯O hydrogen-bonded two-dimensional layers and β-sheet with —HN—(CH₂)₄—NH— spacer

In this series the single crystals suitable for X-ray diffraction were obtained for 1c, 3c and 4c. Compound 2c failed to form suitable single crystals despite several trails. The crystal structures and the solid-state reactivates of 1c and 3c were published by us earlier. Molecules 1c and 3c were found to exhibit two-dimensional layers via amide-to-amide hydrogen bonds [1c: N⋯O, N—H⋯O: 2.901 (4) Å, 161°] and contain the required double bond alignment for [2 + 2] polymerization as anticipated. In particular, within the layers the double bonds are aligned with a distance (d₁) of 3.812 Å and C=C⋯C=C torsion (τ₂) of 0°. The comparison of XRPD patterns of 2c with those of 1c indicates that the crystal structures of 2c could be similar to that of 1c (Fig. 9). Both 1c and 3c contain half molecules in the asymmetric units. The geometries of the molecules of 1c and 3c were found to be somewhat similar to those of the above structures as the planes of C=C—C=O create almost right angles (73.6° in 1c and 74.8° in 3c) with that of the spacer —C—C—C—C— plane, and the amide planes are parallel to each other. Further, the central butyl amine moiety is found to have non-planar geometry with the N—C—C—C torsion angles of 59° and 62° in 1c and 3c, respectively.

Figure 9
XRPD patterns of (a) 1c (calculated); (b) 2c (observed); note the matching of patterns.

The crystal structure of 4c is found to be totally different from the above structures as it includes water in the crystal lattice. The crystals exhibit space group P2₁/c and the asymmetric unit is constituted by half a unit of 4c and one water molecule. The geometry also differs from the above structures as the central plane of the alkyl spacer makes an angle of 64° with that of C=C—C=O. Unlike the above two structures the —N—(CH₂)₄—N— fragment exhibits all anti geometry with N—C—C—C angles of 180°. The molecules assemble via amide-to-amide N—H⋯O hydrogen bonds to form the β-sheet network along the b axis with a repeat distance of 4.68 Å. These sheets are further connected via Ow—H⋯N_pyridine hydrogen bonds to the chain of water molecules leading to the formation of a two-dimensional layer in which each water has three connectivity (Fig. 10). These layers stack on each other via C—H⋯π and C—H⋯O interactions.

Figure 10
Illustrations for the crystal structure of 4c: (a) linking of β-sheets via H₂O molecules to form a two-dimensional layer; (b) packing of the layers such that the double bonds are aligned for a possible [2 + 2] photopolymerization reaction.

3.4. β-sheets with —HN—(CH₂)₆—NH— spacer

In accordance with our previous studies the introduction of a hexyl spacer resulted in the β-sheet structures in a consistent manner. Molecules 1d and 2d crystallized in P2₁/c and 4d crystallized in P2₁/n. Single crystals of 3d could not be obtained despite several trails by varying solvents and their combinations. The asymmetric unit of 1d is constituted by one molecule while those of 2d and 4d are constituted by half a unit of the corresponding molecule and one H₂O molecule. The molecular geometries are somewhat similar in all three cases as the amide planes are in-plane with the plane of hexyl spacer, which exhibits all anti geometry. In all three structures the molecules assemble in β-sheets via amide-to-amide N—H⋯O hydrogen bonds, along the b-axis in 1d and 4d, and along the c-axis in 2d with the same repeat distance of 4.9 Å. In 2d and 4d, neither the water molecules nor the pyridyl groups interfere in amide-to-amide. Rather water molecules form zigzag chains via O—H⋯O hydrogen bonds and join the β-sheets in two-dimensional layers via Ow—H⋯N_pyridine hydrogen bonds. Interestingly, given the positional differences of pyridines in 2d and 4d, the layers have different geometries although they have the same hydrogen-bonding connectivities. In 2d the layers are highly corrugated, while they are planar in 4d (Fig. 11). In both layers water molecules exhibit 3-connectivity: two Ow—H⋯Ow with neighbouring water molecules and O—H⋯N with pyridine moieties. We note here that the crystal structure of 4d was found to be isostructural with that of 4c. The layers pack on each other with an interlayer separation of 4 Å in 2d and 4d, whereas in 1d the β-sheets pack in a parallel fashion. The XRPD of 3d was found to be similar to that of 1d, indicating it may also have similar β-sheet formation (Fig. S30).

Figure 11
Illustrations for the crystal structure of 2d: (a) packing diagram, note the linking of β-sheets into the three-dimensional network by water molecules; (b) linking of β-sheets of 2d by the zigzag chain of water molecules.

3.5. Molecular structure versus hydrogen-bonding networks

In previous studies on amides and reverse amides it was found that the geometry of the molecule and position of the pyridine groups play a key role in the competition of acceptors C=O of amide and the N atom of pyridine to form hydrogen bonds with the N—H group of amides. In particular, the inter-planar angle (θ) between the amide group and the terminal aromatic ring tailors the resultant hydrogen bonds. The θ-value of less than 20° results in the formation of N—H⋯N hydrogen bonds, while above 20° results in the formation of N—H⋯O hydrogen bonds. This phenomenon was also explored using a larger set of compounds from the CSD. In the present series it was found that this hypothesis holds good with the exception of three compounds, namely 1a, 1c and 3c, which form amide-to-amide hydrogen bonds despite having a θ-value below 20°, i.e. 8.45°, 12.83° and 8.42°, respectively (Table S2).

The probable reasons could be due to their unusual molecular geometries which differ totally from the rest of the structures presented here as they deviate heavily from linearity. Further, it was found earlier that the phenyl and the 3-pyridyl substituted derivatives do not form hydrates, while the 4-pyridyl derivatives do exhibit such a tendency. Similarly, out of four 4-pyridyl derivatives studied here, two form hydrates. Interestingly, the present studies show that the 2-pyridyl groups also have a similar tendency to form such hydrates as two out of three form hydrates.

3.6. Trends in the melting points of the homologues series

We are in agreement with the general conception that the decrease in melting points was observed with an increase in the number of CH₂ groups, with the caveat that the derivatives with a butyl spacer (1c, 2c, 3c and 4c) deviate from such trends (Hall & Reid, 1943 ; Thalladi, Boese & Weiss, 2000 ; Thalladi, Nüsse & Boese, 2000 ). The butyl derivatives 1c, 2c and 3c are found to exhibit higher melting points than the corresponding ethyl (1b, 2b, 3b) and hexyl derivatives (1d, 2d, 3d and 4d). A further decrease in the melting point was observed for hydrates compared with their respective analogues. Phenyl and 4-pyrydyl derivatives have been shown to have higher melting points than the 3-pyridyl and 2-pyridyl derivatives. A similar tendency was also observed in the melting points of amides and reverse amides (Mukherjee & Biradha, 2011a). No correlation of melting points was observed with either the dimensionality of the network or nature of the hydrogen bonds (N—H⋯O versus N—H⋯N) (Fig. 12). Further, in a given series a linear increase in the densities of the derivatives was observed with an increase in the number of —(CH₂)— groups with the exception of 1a. Interestingly, the densities of 4-pyridyl derivatives are found to be higher than those of the other three homologues. In contrast, the homologous series containing a phenyl substituent was found to exhibit lower densities than the other three series (Fig. S38).

Figure 12
Trends observed in the melting points of the homologous series.

3.7. Solid-state reactivities of 1c, 2b, 2c, 3a, 4a, 3c and 4c

The crystal structure analysis of 2b reveals that the double bonds are aligned for a single [2 + 2] reaction with a C⋯C distance (d₁) between the double-bonded C atoms of 3.84 Å and C=C⋯C=C torsion of (τ₂) 0°. The ¹H NMR spectra of irradiated 2b in DMSO-d⁶ shows the appearance of cyclobutane protons at 4.44 and 4.03 p.p.m. with the presence of olefinic protons. From these observations it can be concluded that 2b was converted to a single dimer product in 59% yield after 72 h of irradiation in sunlight (Fig. 13).

Figure 13
¹H NMR in DMSO-d⁶ (a) of 2b, the peaks at 7.45 and 7.04 p.p.m. represent olefin protons; (b) of the single dimer of 2b, the presence of cyclobutane protons at 4.44 and 4.03 p.p.m. with unreacted olefin doublet (H_a and H_b) confirms the single [2 + 2] product.

As it was described earlier, the materials 1c, 2c, 3c and 4c have a required alignment for solid-state [2 + 2] polymerization reactions. The compounds 1c and 3c were shown by us earlier to undergo a polymerization reaction in a SCSC manner to yield crystalline covalent polymers. Although single crystals of 2c were not obtained, the comparison of XRPD patterns of 2c revealed that it also contains similar packing with two-dimensional (4,4)-layers as in 1c and 3c. Therefore, a polycrystalline material of 2c was irradiated in sunlight for 96 h. The irradiated product was found to be insoluble in common organic solvents similar to those of 1c and 3c. However, it was found to be soluble in DMSO or aqueous solution with a drop of HCl, HNO₃ or H₂SO₄.

The ¹H NMR spectra of an irradiated sample of 2c in DMSO-d⁶ and one drop of H₂SO₄ revealed that the reaction proceeds through the formation of oligomers as the resultant spectra contains some new peaks in addition to the peaks of the monomer and polymer. In the spectra the cyclobutane peaks of a polymer appeared at 4.27 and 4.64 p.p.m. and also the n-butyl protons of the polymer were found to exhibit an up-field shift from monomer to polymer, i.e. 3.22 to 2.56 p.p.m. and 1.51 to 0.77 p.p.m. For oligomers, the cyclobutane peaks appeared at the same p.p.m. as the polymer, however, the corresponding n-butyl peaks appeared at 3.05, 1.22 and 1.08 p.p.m.. From ¹H NMR, the yield of the reaction including oligomers was found to be 45%. The result of the polymerization reaction observed here is in line with that of 3c albeit the yield of the polymer is not 100% in the present case. The unreacted 2c and oligomers were removed by repeatedly washing the irradiated material of 2c with hot methanol. The ¹H NMR of the separated polymer in DMSO-d⁶ with one drop of H₂SO₄ reveals the presence of cyclobutane protons at 4.27 and 4.64 p.p.m. with n-butyl protons at 2.57 and 0.77 p.p.m. and the absence of olefin protons (Fig. 14). However, unlike the polymer of 3c, the polymeric material of 2c does not result in the formation of plastic films.

Figure 14
¹H-NMR spectra recorded at various stages of irradiation of compound 2c: (a) before irradiation, (b) after irradiation (monomer, oligomers and polymer) and (c) after separation of polymer from monomer and oligomers.

The molecular weight of the polymer (2c) was determined using MALDI-TOF (matrix-assisted laser desorption/ionization time-of-flight) with 2,5-dihydroxy benzoic acid (DHB) as a matrix in solution. The highest molecular ion peak was observed at 4415 (m/z), which corresponds to 12-mer of 2c (Fig. 15).

Figure 15
MALDI-TOF mass data for 2c (irradiated).

Although 4c forms β-sheet type N—H⋯O hydrogen bonds, the double bonds of 4c are aligned with the other layer and fulfil [2 + 2] photopolymerization criteria with appropriate geometrical parameters: d₁ = 4.18 Å and τ₂ = 0°. However, 4c was found to be photostable even after prolonged irradiation. The probable reason could be loss of the lattice water which triggers the structural transformation to an unreactive form. Indeed, it was found that the XRPD pattern of 4c which is recorded at room temperature does not match the calculated XRPD pattern of 4c indicating the loss of water. The single-crystal data for this material was collected at low temperature.

Similarly, compounds 3a and 4a were found to be photostable despite the possibility of single and double [2 + 2] reactions, respectively. The d₁ and τ₂ values for 3a and 4a are 3.909 Å and 0.74°, and 3.779 Å and 0°, respectively. The probable reason could be that in 3a the double bonds exhibit the higher displacement value of 1.9 Å, whereas in 4a the existence of infinite stacks rather than discrete dimers might have prevented the reaction (Gnanaguru et al., 1985 ; Murthy et al., 1987 ; Nagarathinam et al., 2008 ; Yang et al., 2009 ).

4. Conclusions

The homologous series exhibit variation in their crystal structures depending upon the spacers and end groups such as phenyl, 2-pyridyl, 3-pyridyl or 4-pyridyl. Unlike in previously studied series, in the current one the hydrazine spacer and 2-pyridyl derivatives were included for the first time. Some of the structural aspects observed here have direct correlations with those of amide/reverse amide homologues. For example, amide derivatives with a butyl spacer have previously been shown to form two-dimensional layers via N—H⋯O hydrogen bonds for both 3-pyridyl and 4-pyridyl derivatives (Sarkar & Biradha, 2006). Similarly, in the current study the phenyl, 2-pyridyl and 3-pyridyl derivatives containing a butyl spacer form such a two-dimensional N—H⋯O hydrogen-bonded layer. However, the 4-pyridyl derivative deviates as it forms β-sheets which are linked further by water molecules. Further, all the derivatives containing a hexyl spacer exhibited β-sheets irrespective of the end attachments, which is in agreement with the amide derivatives containing a hexyl spacer and 3-pyridyl or 4-pyridyl attachments.

Supporting information

CCDC references: 1055532; 1055533; 1055534; 1055535; 1055536; 1055537; 1055538; 1055539; 1055540; 1055541; 1055542

Crystal structure: contains datablocks 1a, 1b, 1d, 2a, 2b, 2d, 3a, 3b, 4b, 4c, 4d. DOI: https://doi.org/10.1107/S2052252515009987/yc5005sup1.cif

Structure factors: contains datablock kb_mg_080. DOI: https://doi.org/10.1107/S2052252515009987/yc50051asup2.hkl

Structure factors: contains datablock kb_mg_2. DOI: https://doi.org/10.1107/S2052252515009987/yc50051bsup3.hkl

Structure factors: contains datablock kbmg109. DOI: https://doi.org/10.1107/S2052252515009987/yc50051dsup4.hkl

Structure factors: contains datablock kbmg181. DOI: https://doi.org/10.1107/S2052252515009987/yc50052asup5.hkl

Structure factors: contains datablock kbmg146. DOI: https://doi.org/10.1107/S2052252515009987/yc50052bsup6.hkl

Structure factors: contains datablock kbmg154. DOI: https://doi.org/10.1107/S2052252515009987/yc50052dsup7.hkl

Structure factors: contains datablock kb_rs_501. DOI: https://doi.org/10.1107/S2052252515009987/yc50053asup8.hkl

Structure factors: contains datablock kbmg011. DOI: https://doi.org/10.1107/S2052252515009987/yc50053bsup9.hkl

Structure factors: contains datablock kbgt001. DOI: https://doi.org/10.1107/S2052252515009987/yc50054bsup10.hkl

Structure factors: contains datablock kbmg176. DOI: https://doi.org/10.1107/S2052252515009987/yc50054csup11.hkl

Structure factors: contains datablock kbmg112. DOI: https://doi.org/10.1107/S2052252515009987/yc50054dsup12.hkl

Computing details top

For all compounds, program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997).

(1a) top

Crystal data top

C₁₈H₁₆N₂O₂	F(000) = 616
M_r = 292.33	D_x = 1.239 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 18.451 (9) Å	θ = 2.2–25.0°
b = 10.540 (5) Å	µ = 0.08 mm⁻¹
c = 8.157 (4) Å	T = 293 K
β = 98.824 (12)°	Block, white
V = 1567.6 (13) Å³	0.22 × 0.15 × 0.10 mm
Z = 4

Data collection top

Bruker CCD APEX-2 diffractometer	1377 independent reflections
Radiation source: fine-focus sealed tube	775 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.064
hemisphere scans	θ_max = 25.0°, θ_min = 2.2°
Absorption correction: empirical (using intensity measurements) Sadabs	h = −21→21
T_min = 0.985, T_max = 0.992	k = −12→12
7785 measured reflections	l = −9→9

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.055	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.193	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
S = 1.10	(Δ/σ)_max < 0.001
1377 reflections	Δρ_max = 0.18 e Å⁻³
101 parameters	Δρ_min = −0.16 e Å⁻³
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.010 (3)

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C11	0.29320 (13)	0.1397 (2)	0.3674 (3)	0.0535 (7)
C12	0.31705 (16)	0.0734 (3)	0.5099 (4)	0.0767 (10)
H12	0.2837	0.0235	0.5559	0.092*
C13	0.38838 (16)	0.0781 (4)	0.5870 (4)	0.0885 (12)
H13	0.4028	0.0311	0.6829	0.106*
C14	0.43840 (16)	0.1518 (3)	0.5235 (5)	0.0802 (10)
H14	0.4871	0.1547	0.5744	0.096*
C15	0.41553 (15)	0.2205 (3)	0.3847 (4)	0.0778 (10)
H15	0.4490	0.2720	0.3416	0.093*
C16	0.34386 (15)	0.2158 (3)	0.3057 (4)	0.0681 (9)
H16	0.3296	0.2640	0.2107	0.082*
C17	0.21756 (14)	0.1355 (2)	0.2808 (3)	0.0544 (8)
H17	0.2075	0.1839	0.1847	0.065*
C18	0.16157 (13)	0.0706 (2)	0.3239 (3)	0.0522 (7)
H18	0.1687	0.0219	0.4201	0.063*
C19	0.08865 (13)	0.0747 (2)	0.2220 (3)	0.0487 (7)
O11	0.07633 (9)	0.12526 (18)	0.0847 (2)	0.0639 (7)
N21	0.03594 (10)	0.0154 (2)	0.2903 (2)	0.0557 (7)
H21	0.0469	−0.0226	0.3842	0.067*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C11	0.0421 (15)	0.0630 (17)	0.0538 (16)	−0.0005 (13)	0.0018 (12)	−0.0037 (13)
C12	0.0461 (18)	0.097 (2)	0.082 (2)	−0.0161 (15)	−0.0058 (15)	0.0215 (18)
C13	0.057 (2)	0.102 (3)	0.097 (3)	−0.0147 (18)	−0.0181 (18)	0.032 (2)
C14	0.0464 (18)	0.087 (2)	0.102 (3)	−0.0051 (17)	−0.0070 (17)	−0.003 (2)
C15	0.0503 (19)	0.076 (2)	0.108 (3)	−0.0194 (16)	0.0150 (18)	−0.007 (2)
C16	0.0615 (19)	0.0664 (19)	0.0742 (19)	−0.0075 (15)	0.0035 (15)	0.0068 (15)
C17	0.0487 (16)	0.0618 (18)	0.0503 (15)	0.0012 (13)	0.0003 (12)	−0.0058 (13)
C18	0.0429 (16)	0.0663 (17)	0.0440 (15)	0.0055 (12)	−0.0043 (12)	−0.0052 (12)
C19	0.0420 (15)	0.0592 (16)	0.0411 (14)	0.0047 (12)	−0.0051 (11)	−0.0094 (12)
O11	0.0557 (12)	0.0826 (15)	0.0483 (12)	0.0018 (10)	−0.0083 (9)	0.0032 (10)
N21	0.0361 (11)	0.0785 (16)	0.0467 (13)	−0.0017 (10)	−0.0115 (9)	0.0045 (11)

Geometric parameters (Å, º) top

C11—C12	1.370 (4)	C15—C16	1.380 (4)
C11—C16	1.384 (3)	C17—C18	1.330 (3)
C11—C17	1.465 (4)	C18—C19	1.470 (3)
C12—C13	1.370 (4)	C19—O11	1.229 (3)
C13—C14	1.367 (4)	C19—N21	1.347 (3)
C14—C15	1.356 (4)	N21—N21ⁱ	1.387 (4)

C12—C11—C16	117.2 (3)	C15—C16—C11	120.2 (3)
C12—C11—C17	123.5 (3)	C18—C17—C11	127.5 (3)
C16—C11—C17	119.3 (3)	C17—C18—C19	121.1 (3)
C11—C12—C13	122.1 (3)	O11—C19—N21	122.3 (2)
C14—C13—C12	120.3 (3)	O11—C19—C18	123.6 (2)
C15—C14—C13	118.5 (3)	N21—C19—C18	114.1 (2)
C14—C15—C16	121.6 (3)	C19—N21—N21ⁱ	120.2 (2)

Symmetry code: (i) −x, y, −z+1/2.

(1b) top

Crystal data top

C₂₀H₂₀N₂O₂	F(000) = 340
M_r = 320.38	D_x = 1.313 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 17.899 (3) Å	Cell parameters from 1579 reflections
b = 4.8544 (9) Å	θ = 1.2–26.0°
c = 9.5259 (16) Å	µ = 0.09 mm⁻¹
β = 101.847 (4)°	T = 273 K
V = 810.1 (2) Å³	Block, white
Z = 2	0.22 × 0.17 × 0.11 mm

Data collection top

Bruker CCD APEX-2 diffractometer	1579 independent reflections
Radiation source: fine-focus sealed tube	1244 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.037
hemisphere scans	θ_max = 26.0°, θ_min = 1.2°
Absorption correction: empirical (using intensity measurements) sadabs	h = −22→22
T_min = 0.983, T_max = 0.991	k = −5→5
6423 measured reflections	l = −11→11

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.037	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.107	w = 1/[σ²(F_o²) + (0.010P)² + 0.9374P] where P = (F_o² + 2F_c²)/3
S = 1.21	(Δ/σ)_max < 0.001
1579 reflections	Δρ_max = 0.24 e Å⁻³
110 parameters	Δρ_min = −0.25 e Å⁻³
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0086 (11)

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
C7	0.26742 (11)	0.2184 (5)	0.7661 (2)	0.0168 (5)
H7	0.2641	0.4049	0.7433	0.020*
C8	0.32637 (11)	0.0795 (5)	0.7378 (2)	0.0152 (5)
H8	0.3322	−0.1050	0.7641	0.018*
C9	0.38338 (11)	0.2092 (5)	0.6654 (2)	0.0145 (5)
N1	0.42726 (9)	0.0302 (4)	0.61157 (17)	0.0150 (4)
H10	0.4210	−0.1435	0.6226	0.018*
C11	0.48509 (11)	0.1220 (5)	0.5351 (2)	0.0159 (5)
H11A	0.5267	0.2094	0.6015	0.019*
H11B	0.4633	0.2560	0.4628	0.019*
O1	0.38996 (8)	0.4614 (3)	0.65419 (15)	0.0190 (4)
C1	0.08866 (12)	−0.1368 (5)	0.9407 (2)	0.0207 (5)
H1	0.0493	−0.2168	0.9768	0.025*
C2	0.16255 (12)	−0.2346 (5)	0.9828 (2)	0.0210 (5)
H2	0.1728	−0.3792	1.0479	0.025*
C3	0.22127 (11)	−0.1179 (5)	0.9283 (2)	0.0180 (5)
H3	0.2707	−0.1850	0.9570	0.022*
C4	0.20683 (11)	0.0993 (5)	0.8308 (2)	0.0158 (5)
C5	0.13232 (12)	0.1988 (5)	0.7911 (2)	0.0199 (5)
H5	0.1219	0.3464	0.7279	0.024*
C6	0.07364 (12)	0.0795 (5)	0.8453 (2)	0.0215 (5)
H6	0.0241	0.1456	0.8171	0.026*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C7	0.0190 (10)	0.0140 (12)	0.0176 (10)	−0.0018 (9)	0.0044 (8)	−0.0004 (9)
C8	0.0173 (10)	0.0122 (12)	0.0163 (10)	−0.0021 (9)	0.0038 (8)	0.0007 (9)
C9	0.0141 (9)	0.0141 (12)	0.0144 (9)	−0.0018 (9)	0.0006 (7)	0.0000 (9)
N1	0.0177 (8)	0.0086 (10)	0.0206 (9)	−0.0014 (8)	0.0085 (7)	0.0011 (7)
C11	0.0171 (10)	0.0140 (12)	0.0178 (10)	−0.0005 (9)	0.0064 (8)	0.0021 (9)
O1	0.0209 (8)	0.0118 (9)	0.0259 (8)	−0.0016 (7)	0.0085 (6)	0.0005 (7)
C1	0.0198 (10)	0.0247 (14)	0.0202 (10)	−0.0052 (10)	0.0103 (8)	−0.0030 (10)
C2	0.0251 (11)	0.0224 (13)	0.0163 (10)	−0.0002 (10)	0.0066 (8)	0.0028 (9)
C3	0.0165 (10)	0.0206 (13)	0.0167 (10)	0.0016 (10)	0.0032 (8)	−0.0009 (9)
C4	0.0182 (10)	0.0150 (12)	0.0151 (9)	−0.0017 (9)	0.0053 (8)	−0.0053 (9)
C5	0.0217 (11)	0.0181 (13)	0.0210 (10)	0.0040 (10)	0.0070 (8)	0.0021 (9)
C6	0.0167 (10)	0.0252 (14)	0.0237 (11)	0.0034 (10)	0.0070 (8)	−0.0029 (10)

Geometric parameters (Å, º) top

C7—C8	1.326 (3)	C1—C6	1.379 (3)
C7—C4	1.471 (3)	C1—C2	1.385 (3)
C7—H7	0.9300	C1—H1	0.9300
C8—C9	1.484 (3)	C2—C3	1.385 (3)
C8—H8	0.9300	C2—H2	0.9300
C9—O1	1.237 (3)	C3—C4	1.394 (3)
C9—N1	1.342 (3)	C3—H3	0.9300
N1—C11	1.452 (2)	C4—C5	1.396 (3)
N1—H10	0.8600	C5—C6	1.388 (3)
C11—C11ⁱ	1.511 (4)	C5—H5	0.9300
C11—H11A	0.9700	C6—H6	0.9300
C11—H11B	0.9700

C8—C7—C4	124.8 (2)	C6—C1—C2	119.8 (2)
C8—C7—H7	117.6	C6—C1—H1	120.1
C4—C7—H7	117.6	C2—C1—H1	120.1
C7—C8—C9	122.0 (2)	C3—C2—C1	120.3 (2)
C7—C8—H8	119.0	C3—C2—H2	119.8
C9—C8—H8	119.0	C1—C2—H2	119.8
O1—C9—N1	122.29 (18)	C2—C3—C4	120.5 (2)
O1—C9—C8	123.17 (19)	C2—C3—H3	119.7
N1—C9—C8	114.53 (19)	C4—C3—H3	119.7
C9—N1—C11	121.77 (18)	C3—C4—C5	118.58 (19)
C9—N1—H10	119.1	C3—C4—C7	121.65 (19)
C11—N1—H10	119.1	C5—C4—C7	119.7 (2)
N1—C11—C11ⁱ	109.6 (2)	C6—C5—C4	120.6 (2)
N1—C11—H11A	109.8	C6—C5—H5	119.7
C11ⁱ—C11—H11A	109.8	C4—C5—H5	119.7
N1—C11—H11B	109.8	C1—C6—C5	120.2 (2)
C11ⁱ—C11—H11B	109.8	C1—C6—H6	119.9
H11A—C11—H11B	108.2	C5—C6—H6	119.9

Symmetry code: (i) −x+1, −y, −z+1.

(1d) top

Crystal data top

C₂₄H₂₈N₂O₂	F(000) = 808
M_r = 376.48	D_x = 1.207 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 20.243 (5) Å	Cell parameters from 1665 reflections
b = 4.9756 (14) Å	θ = 2.0–25.0°
c = 20.839 (6) Å	µ = 0.08 mm⁻¹
β = 99.148 (8)°	T = 293 K
V = 2072.2 (10) Å³	Plate like, white
Z = 4	0.32 × 0.21 × 0.18 mm

Data collection top

Bruker CCD APEX-2 diffractometer	3439 independent reflections
Radiation source: fine-focus sealed tube	1665 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.123
hemisphere scans	θ_max = 25.0°, θ_min = 2.0°
Absorption correction: empirical (using intensity measurements) sadabs	h = −24→24
T_min = 0.985, T_max = 0.986	k = −5→5
21630 measured reflections	l = −23→24

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.079	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.201	H atoms treated by a mixture of independent and constrained refinement
S = 0.95	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
3439 reflections	(Δ/σ)_max < 0.001
253 parameters	Δρ_max = 0.18 e Å⁻³
0 restraints	Δρ_min = −0.18 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O11	0.16814 (14)	0.8440 (5)	0.31534 (13)	0.0701 (9)
C11	0.31957 (17)	0.5752 (8)	0.47170 (17)	0.0496 (10)
C12	0.3636 (2)	0.3761 (10)	0.4615 (2)	0.0873 (15)
H12	0.3567	0.2789	0.4229	0.105*
C13	0.4182 (2)	0.3192 (11)	0.5082 (3)	0.1016 (18)
H13	0.4478	0.1841	0.5007	0.122*
C14	0.4291 (2)	0.4584 (12)	0.5649 (2)	0.0903 (16)
H14	0.4657	0.4193	0.5964	0.108*
C15	0.3858 (3)	0.6547 (13)	0.5747 (2)	0.1003 (18)
H15	0.3927	0.7512	0.6134	0.120*
C16	0.3318 (2)	0.7138 (10)	0.5286 (2)	0.0784 (14)
H16	0.3030	0.8514	0.5363	0.094*
C17	0.26320 (17)	0.6471 (7)	0.42176 (17)	0.0492 (9)
H17	0.2448	0.8165	0.4256	0.059*
C18	0.23513 (18)	0.5011 (7)	0.37177 (17)	0.0523 (10)
H18	0.2495	0.3248	0.3685	0.063*
C19	0.18211 (18)	0.6045 (8)	0.32079 (17)	0.0480 (9)
O21	−0.18393 (13)	−0.4679 (5)	−0.06957 (13)	0.0716 (9)
C21	−0.33587 (19)	−0.1893 (8)	−0.22411 (17)	0.0547 (10)
C22	−0.3266 (2)	0.0151 (9)	−0.26633 (19)	0.0695 (12)
H22	−0.2860	0.1065	−0.2609	0.083*
C23	−0.3760 (2)	0.0858 (10)	−0.3160 (2)	0.0800 (14)
H23	−0.3691	0.2276	−0.3432	0.096*
C24	−0.4357 (2)	−0.0507 (10)	−0.3260 (2)	0.0758 (14)
H24	−0.4687	−0.0055	−0.3607	0.091*
C25	−0.4462 (2)	−0.2517 (10)	−0.2850 (2)	0.0819 (14)
H25	−0.4871	−0.3411	−0.2904	0.098*
C26	−0.3964 (2)	−0.3228 (9)	−0.2354 (2)	0.0810 (14)
H26	−0.4037	−0.4653	−0.2085	0.097*
C27	−0.28519 (18)	−0.2705 (7)	−0.16984 (18)	0.0552 (10)
H27	−0.2868	−0.4483	−0.1564	0.066*
C28	−0.23715 (17)	−0.1197 (7)	−0.13755 (17)	0.0513 (10)
H28	−0.2330	0.0577	−0.1504	0.062*
C29	−0.19003 (17)	−0.2248 (8)	−0.08177 (18)	0.0519 (10)
N31	0.15168 (14)	0.4220 (6)	0.27998 (13)	0.0507 (8)
H31	0.1623	0.2559	0.2866	0.061*
N32	−0.15478 (14)	−0.0403 (6)	−0.04425 (14)	0.0538 (8)
H32	−0.1598	0.1261	−0.0551	0.065*
C31	0.10147 (18)	0.4888 (7)	0.22482 (17)	0.0533 (10)
H31A	0.1228	0.5774	0.1921	0.064*
H31B	0.0697	0.6139	0.2386	0.064*
C32	0.06463 (17)	0.2459 (7)	0.19545 (17)	0.0519 (10)
H32A	0.0964	0.1207	0.1819	0.062*
H32B	0.0432	0.1577	0.2282	0.062*
C33	0.01243 (18)	0.3140 (7)	0.13789 (17)	0.0536 (10)
H33A	0.0335	0.4119	0.1064	0.064*
H33B	−0.0207	0.4312	0.1521	0.064*
C34	−0.02279 (17)	0.0675 (7)	0.10498 (17)	0.0516 (10)
H34A	0.0104	−0.0520	0.0917	0.062*
H34B	−0.0449	−0.0280	0.1362	0.062*
C35	−0.07410 (17)	0.1373 (7)	0.04596 (17)	0.0504 (10)
H35A	−0.1074	0.2563	0.0592	0.061*
H35B	−0.0521	0.2327	0.0147	0.061*
C36	−0.10849 (17)	−0.1082 (7)	0.01383 (17)	0.0509 (10)
H36A	−0.0750	−0.2316	0.0026	0.061*
H36B	−0.1326	−0.1986	0.0443	0.061*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O11	0.077 (2)	0.0424 (18)	0.081 (2)	0.0035 (14)	−0.0183 (16)	0.0017 (15)
C11	0.044 (2)	0.057 (3)	0.045 (2)	−0.0105 (19)	−0.0007 (18)	0.002 (2)
C12	0.089 (3)	0.085 (4)	0.077 (3)	0.022 (3)	−0.022 (3)	−0.020 (3)
C13	0.085 (4)	0.100 (4)	0.106 (4)	0.033 (3)	−0.024 (3)	−0.009 (4)
C14	0.073 (3)	0.106 (4)	0.079 (4)	−0.008 (3)	−0.026 (3)	0.022 (3)
C15	0.083 (4)	0.155 (5)	0.057 (3)	0.003 (4)	−0.008 (3)	−0.024 (3)
C16	0.069 (3)	0.101 (4)	0.061 (3)	0.002 (3)	−0.003 (3)	−0.020 (3)
C17	0.049 (2)	0.046 (2)	0.052 (2)	−0.0014 (18)	0.0065 (19)	−0.0045 (19)
C18	0.055 (2)	0.040 (2)	0.058 (2)	0.0024 (19)	−0.002 (2)	0.006 (2)
C19	0.052 (2)	0.042 (2)	0.048 (2)	0.0004 (19)	0.0020 (19)	−0.0010 (19)
O21	0.082 (2)	0.0348 (17)	0.085 (2)	−0.0017 (14)	−0.0250 (16)	0.0029 (14)
C21	0.062 (3)	0.049 (2)	0.050 (2)	0.006 (2)	0.001 (2)	−0.005 (2)
C22	0.061 (3)	0.082 (3)	0.063 (3)	0.002 (2)	0.003 (2)	0.012 (3)
C23	0.086 (3)	0.084 (3)	0.067 (3)	0.002 (3)	0.006 (3)	0.024 (3)
C24	0.070 (3)	0.105 (4)	0.048 (3)	0.022 (3)	−0.004 (2)	0.008 (3)
C25	0.064 (3)	0.099 (4)	0.075 (3)	−0.007 (3)	−0.015 (3)	0.010 (3)
C26	0.082 (3)	0.069 (3)	0.079 (3)	−0.017 (3)	−0.029 (3)	0.019 (3)
C27	0.063 (3)	0.038 (2)	0.060 (2)	0.001 (2)	−0.006 (2)	0.0050 (19)
C28	0.052 (2)	0.036 (2)	0.062 (2)	−0.0025 (18)	−0.0038 (19)	0.0001 (19)
C29	0.047 (2)	0.043 (2)	0.064 (3)	0.0012 (19)	0.002 (2)	0.002 (2)
N31	0.0564 (19)	0.0383 (19)	0.0519 (18)	0.0074 (15)	−0.0079 (16)	−0.0042 (15)
N32	0.0546 (19)	0.0328 (18)	0.066 (2)	−0.0034 (15)	−0.0150 (16)	−0.0028 (16)
C31	0.061 (2)	0.041 (2)	0.053 (2)	−0.0013 (19)	−0.0030 (19)	0.0029 (19)
C32	0.056 (2)	0.046 (2)	0.051 (2)	−0.0042 (19)	0.0012 (19)	−0.0009 (18)
C33	0.061 (2)	0.043 (2)	0.052 (2)	0.0013 (19)	−0.0063 (19)	−0.0008 (19)
C34	0.046 (2)	0.049 (2)	0.056 (2)	−0.0037 (18)	−0.0018 (18)	−0.001 (2)
C35	0.051 (2)	0.042 (2)	0.055 (2)	0.0008 (18)	−0.0029 (19)	−0.0016 (18)
C36	0.050 (2)	0.041 (2)	0.058 (2)	0.0025 (17)	−0.0019 (19)	−0.0016 (19)

Geometric parameters (Å, º) top

O11—C19	1.226 (4)	C22—C23	1.365 (5)
C11—C16	1.360 (5)	C23—C24	1.374 (6)
C11—C12	1.372 (5)	C24—C25	1.354 (6)
C11—C17	1.462 (5)	C25—C26	1.371 (5)
C12—C13	1.380 (6)	C27—C28	1.324 (4)
C13—C14	1.357 (6)	C28—C29	1.477 (5)
C14—C15	1.350 (7)	C29—N32	1.336 (4)
C15—C16	1.366 (6)	N31—C31	1.447 (4)
C17—C18	1.322 (4)	N32—C36	1.448 (4)
C18—C19	1.477 (5)	C31—C32	1.499 (5)
C19—N31	1.327 (4)	C32—C33	1.505 (5)
O21—C29	1.238 (4)	C33—C34	1.525 (5)
C21—C26	1.381 (5)	C34—C35	1.518 (5)
C21—C22	1.377 (5)	C35—C36	1.509 (5)
C21—C27	1.458 (5)

C16—C11—C12	117.9 (4)	C22—C23—C24	120.6 (4)
C16—C11—C17	120.7 (4)	C25—C24—C23	119.5 (4)
C12—C11—C17	121.3 (4)	C24—C25—C26	119.8 (4)
C11—C12—C13	120.4 (4)	C25—C26—C21	122.0 (4)
C14—C13—C12	120.6 (5)	C28—C27—C21	127.3 (4)
C15—C14—C13	118.8 (5)	C27—C28—C29	122.0 (3)
C14—C15—C16	121.0 (5)	O21—C29—N32	121.6 (4)
C15—C16—C11	121.3 (5)	O21—C29—C28	122.6 (3)
C18—C17—C11	128.0 (4)	N32—C29—C28	115.8 (3)
C17—C18—C19	123.2 (4)	C19—N31—C31	123.2 (3)
O11—C19—N31	121.9 (3)	C29—N32—C36	122.9 (3)
O11—C19—C18	122.4 (4)	N31—C31—C32	112.4 (3)
N31—C19—C18	115.6 (3)	C33—C32—C31	112.6 (3)
C26—C21—C22	117.0 (4)	C32—C33—C34	113.3 (3)
C26—C21—C27	119.7 (4)	C35—C34—C33	113.0 (3)
C22—C21—C27	123.3 (4)	C36—C35—C34	112.5 (3)
C23—C22—C21	121.1 (4)	N32—C36—C35	111.9 (3)

(2a) top

Crystal data top

C₁₆H₁₄N₄O₂	F(000) = 308
M_r = 294.31	D_x = 1.378 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 4.7315 (10) Å	Cell parameters from 1426 reflections
b = 9.213 (2) Å	θ = 2.5–26.4°
c = 16.390 (4) Å	µ = 0.10 mm⁻¹
β = 97.020 (6)°	T = 100 K
V = 709.1 (3) Å³	Needle, yellow
Z = 2	0.23 × 0.16 × 0.11 mm

Data collection top

Bruker CCD APEX-2 diffractometer	1426 independent reflections
Radiation source: fine-focus sealed tube	1121 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.045
hemisphere scans	θ_max = 26.4°, θ_min = 2.5°
Absorption correction: empirical (using intensity measurements) sadabs	h = −5→5
T_min = 0.982, T_max = 0.990	k = −11→11
8536 measured reflections	l = −18→19

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.132	H atoms treated by a mixture of independent and constrained refinement
S = 0.97	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
1426 reflections	(Δ/σ)_max < 0.001
100 parameters	Δρ_max = 0.29 e Å⁻³
0 restraints	Δρ_min = −0.26 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O11	0.1033 (2)	0.84218 (10)	0.97965 (7)	0.0269 (3)
N11	0.5765 (3)	0.47208 (12)	0.81372 (8)	0.0240 (3)
C11	0.3809 (3)	0.45491 (14)	0.86617 (9)	0.0195 (4)
C12	0.6391 (3)	0.35610 (16)	0.77069 (11)	0.0289 (4)
H12	0.7725	0.3669	0.7339	0.035*
C13	0.5175 (3)	0.22029 (16)	0.77740 (10)	0.0287 (4)
H13	0.5689	0.1425	0.7462	0.034*
C14	0.3192 (3)	0.20367 (15)	0.83128 (10)	0.0285 (4)
H14	0.2338	0.1140	0.8373	0.034*
C15	0.2479 (3)	0.32260 (14)	0.87673 (10)	0.0246 (4)
H15	0.1138	0.3140	0.9135	0.030*
C16	0.3054 (3)	0.58361 (15)	0.91124 (9)	0.0201 (4)
H16	0.1402	0.5792	0.9366	0.024*
C17	0.4544 (3)	0.70650 (14)	0.91884 (9)	0.0193 (4)
H17	0.6264	0.7130	0.8970	0.023*
C18	0.3481 (3)	0.83227 (13)	0.96160 (9)	0.0192 (4)
N21	0.5390 (2)	0.94039 (11)	0.97844 (7)	0.0190 (3)
H21	0.7055	0.9351	0.9626	0.023*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O11	0.0166 (6)	0.0199 (5)	0.0456 (8)	−0.0006 (4)	0.0091 (5)	−0.0065 (4)
N11	0.0236 (7)	0.0230 (6)	0.0259 (7)	0.0016 (5)	0.0052 (6)	−0.0037 (5)
C11	0.0173 (7)	0.0198 (7)	0.0205 (8)	0.0012 (5)	−0.0014 (6)	0.0001 (5)
C12	0.0282 (9)	0.0306 (9)	0.0283 (9)	0.0050 (6)	0.0057 (7)	−0.0051 (7)
C13	0.0327 (9)	0.0235 (8)	0.0281 (9)	0.0075 (6)	−0.0034 (7)	−0.0086 (6)
C14	0.0330 (9)	0.0184 (7)	0.0317 (10)	−0.0008 (6)	−0.0053 (7)	−0.0003 (6)
C15	0.0259 (8)	0.0214 (7)	0.0260 (9)	−0.0005 (6)	0.0011 (7)	−0.0007 (6)
C16	0.0170 (8)	0.0211 (7)	0.0226 (8)	0.0022 (5)	0.0040 (6)	0.0005 (6)
C17	0.0158 (7)	0.0188 (7)	0.0236 (8)	0.0015 (5)	0.0038 (6)	−0.0006 (6)
C18	0.0152 (7)	0.0184 (7)	0.0240 (8)	−0.0001 (5)	0.0019 (6)	0.0006 (6)
N21	0.0138 (6)	0.0157 (6)	0.0291 (8)	0.0009 (4)	0.0087 (5)	−0.0030 (5)

Geometric parameters (Å, º) top

O11—C18	1.2332 (17)	C13—C14	1.373 (2)
N11—C12	1.3334 (18)	C14—C15	1.390 (2)
N11—C11	1.3471 (19)	C16—C17	1.331 (2)
C11—C15	1.3925 (19)	C17—C18	1.4742 (19)
C11—C16	1.4642 (19)	C18—N21	1.3503 (18)
C12—C13	1.387 (2)	N21—N21ⁱ	1.381 (2)

C12—N11—C11	117.24 (12)	C11—C15—C14	118.72 (15)
N11—C11—C15	122.58 (13)	C17—C16—C11	125.23 (13)
N11—C11—C16	117.12 (12)	C16—C17—C18	120.36 (13)
C15—C11—C16	120.28 (14)	O11—C18—N21	121.39 (12)
N11—C12—C13	124.05 (16)	O11—C18—C17	123.86 (12)
C12—C13—C14	118.30 (14)	N21—C18—C17	114.73 (12)
C13—C14—C15	119.12 (14)	C18—N21—N21ⁱ	118.52 (14)

Symmetry code: (i) −x+1, −y+2, −z+2.

(2b) top

Crystal data top

C₁₈H₁₈N₄O_2.4(H2O)	F(000) = 840
M_r = 394.43	D_x = 1.289 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 9.3530 (6) Å	Cell parameters from 3779 reflections
b = 10.9015 (7) Å	θ = 2.0–25.5°
c = 19.9985 (14) Å	µ = 0.10 mm⁻¹
β = 94.547 (2)°	T = 293 K
V = 2032.7 (2) Å³	Rod like, dark brown
Z = 4	0.22 × 0.17 × 0.13 mm

Data collection top

Bruker CCD APEX-2 diffractometer	3779 independent reflections
Radiation source: fine-focus sealed tube	2449 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.044
hemisphere scans	θ_max = 25.5°, θ_min = 2.0°
Absorption correction: empirical (using intensity measurements) sadabs	h = −11→11
T_min = 0.980, T_max = 0.987	k = −13→12
24231 measured reflections	l = −24→24

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.064	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.203	H atoms treated by a mixture of independent and constrained refinement
S = 1.28	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
3779 reflections	(Δ/σ)_max < 0.001
253 parameters	Δρ_max = 0.47 e Å⁻³
0 restraints	Δρ_min = −0.20 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O11	0.1422 (2)	0.0073 (2)	0.33216 (9)	0.0682 (6)
N11	0.2023 (2)	0.1162 (2)	0.58079 (10)	0.0496 (6)
C11	0.2696 (3)	0.0384 (2)	0.54121 (12)	0.0449 (6)
C12	0.2581 (3)	0.1299 (3)	0.64357 (13)	0.0630 (8)
H12	0.2130	0.1838	0.6712	0.076*
C15	0.3895 (3)	−0.0278 (3)	0.56545 (14)	0.0590 (8)
H15	0.4321	−0.0829	0.5376	0.071*
C13	0.3794 (3)	0.0687 (3)	0.67030 (14)	0.0675 (9)
H13	0.4153	0.0824	0.7144	0.081*
C14	0.4452 (3)	−0.0120 (3)	0.63053 (15)	0.0680 (9)
H14	0.5260	−0.0553	0.6471	0.082*
C16	0.2159 (3)	0.0270 (2)	0.47068 (12)	0.0472 (6)
H16	0.2634	−0.0285	0.4449	0.057*
C17	0.1080 (3)	0.0868 (2)	0.44000 (11)	0.0458 (6)
H17	0.0534	0.1388	0.4646	0.055*
C18	0.0715 (3)	0.0731 (3)	0.36711 (12)	0.0476 (6)
N21	−0.4857 (2)	0.1713 (2)	−0.05237 (10)	0.0528 (6)
O21	−0.4538 (2)	0.1537 (2)	0.20594 (10)	0.0776 (7)
C21	−0.5815 (3)	0.1447 (2)	−0.00779 (12)	0.0439 (6)
C22	−0.5326 (3)	0.1699 (3)	−0.11685 (14)	0.0635 (8)
H22	−0.4673	0.1879	−0.1482	0.076*
C23	−0.6716 (3)	0.1435 (3)	−0.14035 (14)	0.0655 (8)
H23	−0.6994	0.1451	−0.1860	0.079*
C24	−0.7669 (3)	0.1150 (3)	−0.09493 (15)	0.0637 (8)
H24	−0.8614	0.0959	−0.1089	0.076*
C25	−0.7213 (3)	0.1151 (3)	−0.02813 (14)	0.0546 (7)
H25	−0.7850	0.0950	0.0036	0.066*
C26	−0.5347 (3)	0.1488 (2)	0.06425 (12)	0.0492 (7)
H26	−0.6006	0.1226	0.0937	0.059*
C27	−0.4100 (3)	0.1854 (3)	0.09104 (12)	0.0501 (7)
H27	−0.3416	0.2110	0.0628	0.060*
C28	−0.3727 (3)	0.1878 (2)	0.16455 (12)	0.0468 (6)
N31	−0.0411 (2)	0.1383 (2)	0.34218 (9)	0.0529 (6)
H31	−0.0852	0.1844	0.3687	0.064*
N32	−0.2429 (2)	0.2299 (2)	0.18279 (10)	0.0544 (6)
H32	−0.1896	0.2525	0.1519	0.065*
C31	−0.0917 (3)	0.1339 (3)	0.27145 (13)	0.0629 (8)
H31A	−0.1444	0.0583	0.2624	0.075*
H31B	−0.0100	0.1340	0.2445	0.075*
C32	−0.1857 (3)	0.2398 (3)	0.25212 (13)	0.0587 (8)
H32A	−0.2642	0.2430	0.2810	0.070*
H32B	−0.1313	0.3153	0.2582	0.070*
O1W	−0.04088 (19)	0.27366 (19)	0.57118 (9)	0.0622 (6)
O2W	−1.0967 (2)	−0.0129 (2)	−0.11611 (11)	0.0764 (7)
O3W	0.2816 (3)	0.0647 (4)	0.22053 (12)	0.1463 (15)
O4W	−0.18024 (19)	0.29995 (19)	0.44367 (9)	0.0606 (6)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O11	0.0773 (13)	0.0850 (16)	0.0424 (10)	0.0317 (12)	0.0051 (9)	−0.0066 (9)
N11	0.0500 (13)	0.0562 (15)	0.0423 (11)	0.0041 (11)	0.0014 (9)	0.0020 (10)
C11	0.0417 (14)	0.0493 (16)	0.0428 (13)	0.0008 (12)	−0.0021 (11)	0.0056 (11)
C12	0.0701 (19)	0.075 (2)	0.0438 (15)	0.0075 (16)	0.0052 (14)	−0.0037 (13)
C15	0.0562 (17)	0.065 (2)	0.0553 (16)	0.0149 (15)	0.0009 (13)	0.0041 (13)
C13	0.067 (2)	0.092 (2)	0.0416 (15)	0.0000 (18)	−0.0094 (14)	0.0054 (15)
C14	0.0590 (18)	0.085 (2)	0.0579 (17)	0.0132 (17)	−0.0106 (14)	0.0123 (16)
C16	0.0469 (14)	0.0504 (17)	0.0447 (14)	0.0032 (12)	0.0066 (12)	−0.0002 (11)
C17	0.0454 (14)	0.0552 (17)	0.0369 (13)	0.0065 (12)	0.0038 (11)	0.0014 (11)
C18	0.0486 (15)	0.0568 (17)	0.0377 (13)	0.0044 (13)	0.0048 (11)	0.0005 (12)
N21	0.0474 (12)	0.0656 (16)	0.0450 (12)	−0.0110 (11)	0.0015 (10)	0.0019 (10)
O21	0.0568 (12)	0.123 (2)	0.0537 (12)	−0.0086 (12)	0.0082 (10)	0.0167 (12)
C21	0.0438 (14)	0.0448 (16)	0.0427 (13)	0.0019 (12)	0.0008 (11)	0.0003 (11)
C22	0.0594 (18)	0.088 (2)	0.0438 (15)	−0.0121 (16)	0.0064 (13)	0.0025 (14)
C23	0.0668 (19)	0.083 (2)	0.0440 (15)	−0.0037 (17)	−0.0097 (14)	−0.0049 (14)
C24	0.0415 (16)	0.079 (2)	0.0687 (19)	−0.0020 (15)	−0.0088 (14)	−0.0098 (16)
C25	0.0412 (15)	0.065 (2)	0.0579 (16)	−0.0019 (13)	0.0054 (12)	−0.0011 (13)
C26	0.0469 (15)	0.0555 (18)	0.0452 (14)	0.0013 (13)	0.0036 (12)	0.0053 (12)
C27	0.0426 (15)	0.0628 (19)	0.0448 (14)	−0.0009 (13)	0.0021 (11)	0.0050 (12)
C28	0.0472 (15)	0.0533 (17)	0.0400 (13)	0.0047 (13)	0.0053 (11)	0.0079 (11)
N31	0.0545 (13)	0.0712 (17)	0.0325 (11)	0.0161 (12)	−0.0004 (9)	−0.0028 (10)
N32	0.0508 (13)	0.0729 (17)	0.0383 (11)	−0.0083 (12)	−0.0042 (9)	0.0096 (10)
C31	0.0700 (19)	0.080 (2)	0.0375 (14)	0.0149 (16)	−0.0030 (13)	−0.0019 (13)
C32	0.0673 (18)	0.063 (2)	0.0428 (14)	0.0052 (15)	−0.0124 (13)	0.0014 (12)
O1W	0.0507 (11)	0.0800 (15)	0.0557 (11)	0.0107 (10)	0.0031 (9)	−0.0056 (10)
O2W	0.0650 (13)	0.0837 (17)	0.0787 (15)	−0.0005 (11)	−0.0047 (11)	−0.0040 (12)
O3W	0.0964 (19)	0.277 (4)	0.0621 (15)	−0.087 (2)	−0.0112 (14)	0.029 (2)
O4W	0.0501 (11)	0.0769 (15)	0.0545 (11)	0.0095 (10)	0.0027 (8)	−0.0008 (9)

Geometric parameters (Å, º) top

O11—C18	1.230 (3)	O21—C28	1.224 (3)
N11—C12	1.329 (3)	C21—C25	1.377 (3)
N11—C11	1.349 (3)	C21—C26	1.473 (3)
C11—C15	1.388 (4)	C22—C23	1.377 (4)
C11—C16	1.465 (3)	C23—C24	1.357 (4)
C12—C13	1.387 (4)	C24—C25	1.370 (4)
C15—C14	1.374 (4)	C26—C27	1.306 (3)
C13—C14	1.365 (4)	C27—C28	1.484 (3)
C16—C17	1.312 (3)	C28—N32	1.321 (3)
C17—C18	1.478 (3)	N31—C31	1.456 (3)
C18—N31	1.334 (3)	N32—C32	1.450 (3)
N21—C22	1.329 (3)	C31—C32	1.484 (4)
N21—C21	1.344 (3)

C12—N11—C11	117.3 (2)	N21—C21—C26	118.7 (2)
N11—C11—C15	121.6 (2)	C25—C21—C26	119.8 (2)
N11—C11—C16	118.5 (2)	N21—C22—C23	124.3 (3)
C15—C11—C16	119.9 (2)	C24—C23—C22	118.1 (3)
N11—C12—C13	123.9 (3)	C23—C24—C25	118.8 (3)
C14—C15—C11	120.0 (3)	C21—C25—C24	120.2 (2)
C12—C13—C14	118.6 (3)	C27—C26—C21	126.6 (2)
C15—C14—C13	118.6 (3)	C26—C27—C28	122.9 (2)
C17—C16—C11	126.9 (2)	O21—C28—N32	121.6 (2)
C16—C17—C18	121.3 (2)	O21—C28—C27	123.7 (2)
O11—C18—N31	122.8 (2)	N32—C28—C27	114.7 (2)
O11—C18—C17	121.8 (2)	C18—N31—C31	122.1 (2)
N31—C18—C17	115.4 (2)	C28—N32—C32	123.5 (2)
C22—N21—C21	117.1 (2)	N31—C31—C32	111.6 (2)
N21—C21—C25	121.5 (2)	N32—C32—C31	110.9 (2)

(2d) top

Crystal data top

C₂₂H₂₆N₄O_2.2(H2O)	F(000) = 444
M_r = 414.50	D_x = 1.233 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 7.6364 (14) Å	Cell parameters from 2068 reflections
b = 30.058 (5) Å	θ = 2.7–25.5°
c = 4.8885 (9) Å	µ = 0.09 mm⁻¹
β = 95.523 (6)°	T = 293 K
V = 1116.9 (3) Å³	Plate like, deep brown
Z = 2	0.27 × 0.19 × 0.11 mm

Data collection top

Bruker CCD APEX-2 diffractometer	2068 independent reflections
Radiation source: fine-focus sealed tube	820 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.168
hemisphere scans	θ_max = 25.5°, θ_min = 2.7°
Absorption correction: empirical (using intensity measurements) sadabs	h = −8→9
T_min = 0.981, T_max = 0.991	k = −36→35
13588 measured reflections	l = −5→5

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.071	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.200	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
S = 0.90	(Δ/σ)_max < 0.001
2068 reflections	Δρ_max = 0.39 e Å⁻³
137 parameters	Δρ_min = −0.19 e Å⁻³
0 restraints	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.026 (6)

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
N11	−0.5217 (4)	0.32279 (12)	0.3902 (7)	0.0620 (10)
O11	−0.1135 (3)	0.42063 (9)	−0.1004 (5)	0.0597 (9)
C11	−0.5518 (5)	0.34939 (13)	0.1694 (8)	0.0508 (11)
C12	−0.6569 (7)	0.29807 (16)	0.4633 (10)	0.0829 (15)
H12	−0.6372	0.2792	0.6141	0.099*
C13	−0.8229 (7)	0.29939 (18)	0.3253 (13)	0.0828 (17)
H13	−0.9129	0.2821	0.3845	0.099*
C14	−0.8537 (6)	0.32582 (17)	0.1048 (12)	0.0822 (16)
H14	−0.9645	0.3273	0.0082	0.099*
C15	−0.7152 (5)	0.35074 (14)	0.0264 (9)	0.0668 (13)
H15	−0.7332	0.3689	−0.1276	0.080*
C16	−0.4048 (5)	0.37584 (12)	0.0924 (8)	0.0526 (11)
H16	−0.4123	0.3861	−0.0879	0.063*
C17	−0.2626 (4)	0.38682 (12)	0.2506 (7)	0.0443 (10)
H17	−0.2495	0.3770	0.4318	0.053*
C18	−0.1233 (5)	0.41438 (12)	0.1483 (8)	0.0438 (10)
N21	−0.0071 (4)	0.43173 (9)	0.3407 (6)	0.0471 (9)
H21	−0.0159	0.4259	0.5111	0.057*
C21	0.1339 (5)	0.46039 (13)	0.2654 (8)	0.0551 (11)
H21A	0.0856	0.4895	0.2174	0.066*
H21B	0.1804	0.4482	0.1033	0.066*
C22	0.2818 (5)	0.46572 (13)	0.4870 (7)	0.0524 (11)
H22A	0.3310	0.4367	0.5367	0.063*
H22B	0.2371	0.4785	0.6488	0.063*
C23	0.4255 (5)	0.49560 (13)	0.3934 (7)	0.0536 (11)
H23A	0.4718	0.4820	0.2355	0.064*
H23B	0.3733	0.5238	0.3339	0.064*
O1W	0.2085 (4)	0.72650 (10)	0.3993 (6)	0.0878 (11)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N11	0.058 (2)	0.070 (2)	0.060 (2)	−0.0181 (19)	0.0157 (19)	0.003 (2)
O11	0.0675 (19)	0.082 (2)	0.0303 (15)	−0.0229 (15)	0.0056 (13)	0.0044 (14)
C11	0.042 (3)	0.059 (3)	0.053 (3)	−0.009 (2)	0.009 (2)	−0.008 (2)
C12	0.085 (4)	0.082 (4)	0.085 (4)	−0.028 (3)	0.027 (3)	0.004 (3)
C13	0.054 (3)	0.088 (4)	0.110 (5)	−0.021 (3)	0.029 (3)	−0.025 (3)
C14	0.045 (3)	0.083 (4)	0.118 (5)	−0.007 (3)	0.004 (3)	−0.024 (4)
C15	0.052 (3)	0.068 (3)	0.079 (3)	−0.005 (2)	0.000 (3)	−0.009 (3)
C16	0.050 (3)	0.062 (3)	0.047 (2)	−0.007 (2)	0.009 (2)	0.000 (2)
C17	0.040 (2)	0.059 (3)	0.035 (2)	−0.0104 (19)	0.0069 (19)	−0.0003 (19)
C18	0.040 (2)	0.053 (2)	0.038 (2)	−0.0048 (19)	0.0041 (19)	0.001 (2)
N21	0.048 (2)	0.059 (2)	0.0345 (18)	−0.0170 (16)	0.0074 (16)	0.0047 (15)
C21	0.049 (3)	0.068 (3)	0.049 (2)	−0.017 (2)	0.006 (2)	0.010 (2)
C22	0.047 (2)	0.068 (3)	0.042 (2)	−0.013 (2)	0.0016 (19)	0.006 (2)
C23	0.047 (3)	0.070 (3)	0.043 (2)	−0.013 (2)	0.0035 (18)	0.011 (2)
O1W	0.068 (2)	0.115 (3)	0.082 (2)	−0.0028 (18)	0.0144 (18)	−0.0003 (19)

Geometric parameters (Å, º) top

N11—C11	1.345 (5)	C16—C17	1.313 (5)
N11—C12	1.348 (5)	C17—C18	1.473 (5)
O11—C18	1.239 (4)	C18—N21	1.335 (4)
C11—C15	1.371 (5)	N21—C21	1.454 (4)
C11—C16	1.455 (5)	C21—C22	1.497 (5)
C12—C13	1.378 (6)	C22—C23	1.522 (5)
C13—C14	1.341 (6)	C23—C23ⁱ	1.491 (7)
C14—C15	1.380 (6)

C11—N11—C12	117.7 (4)	C16—C17—C18	121.6 (4)
N11—C11—C15	120.2 (4)	O11—C18—N21	122.2 (3)
N11—C11—C16	117.1 (4)	O11—C18—C17	122.1 (3)
C15—C11—C16	122.6 (4)	N21—C18—C17	115.6 (3)
N11—C12—C13	123.1 (5)	C18—N21—C21	120.7 (3)
C14—C13—C12	119.5 (5)	N21—C21—C22	114.0 (3)
C13—C14—C15	117.7 (5)	C21—C22—C23	111.2 (3)
C11—C15—C14	121.8 (5)	C23ⁱ—C23—C22	114.7 (4)
C17—C16—C11	126.9 (4)

Symmetry code: (i) −x+1, −y+1, −z+1.

(3a) top

Crystal data top

C₁₆H₁₄N₄O₂	F(000) = 616
M_r = 294.31	D_x = 1.393 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 10.403 (6) Å	Cell parameters from 2475 reflections
b = 7.160 (4) Å	θ = 2.0–25.0°
c = 19.202 (11) Å	µ = 0.10 mm⁻¹
β = 101.156 (17)°	T = 293 K
V = 1403.1 (14) Å³	Plate like, yellow
Z = 4	0.25 × 0.22 × 0.12 mm

Data collection top

Bruker CCD APEX-2 diffractometer	2475 independent reflections
Radiation source: fine-focus sealed tube	1236 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.060
hemisphere scans	θ_max = 25.0°, θ_min = 2.0°
Absorption correction: empirical (using intensity measurements) sadabs	h = −12→12
T_min = 0.976, T_max = 0.989	k = −8→8
15971 measured reflections	l = −21→22

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.080	H atoms treated by a mixture of independent and constrained refinement
S = 1.68	w = 1/[σ²(F_o²) + (0.010P)²] where P = (F_o² + 2F_c²)/3
2475 reflections	(Δ/σ)_max = 0.007
199 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.23 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
N11	0.14943 (19)	0.3152 (3)	−0.27092 (9)	0.0479 (6)
O11	0.13155 (15)	0.3566 (3)	0.06687 (8)	0.0625 (6)
C11	0.0715 (2)	0.3485 (3)	−0.16133 (12)	0.0340 (6)
C12	0.1688 (2)	0.3313 (3)	−0.20060 (11)	0.0447 (7)
H12	0.2550	0.3309	−0.1759	0.054*
C13	0.0251 (2)	0.3174 (3)	−0.30499 (12)	0.0482 (7)
H13	0.0080	0.3038	−0.3541	0.058*
C14	−0.0786 (2)	0.3384 (4)	−0.27182 (12)	0.0503 (7)
H14	−0.1638	0.3415	−0.2979	0.060*
C15	−0.0548 (2)	0.3551 (3)	−0.19895 (12)	0.0454 (7)
H15	−0.1241	0.3707	−0.1753	0.054*
C16	0.0991 (2)	0.3562 (3)	−0.08336 (11)	0.0408 (6)
H16	0.0268	0.3700	−0.0619	0.049*
C17	0.2131 (2)	0.3460 (3)	−0.04051 (11)	0.0429 (7)
H17	0.2885	0.3380	−0.0596	0.051*
C18	0.2248 (2)	0.3470 (3)	0.03710 (12)	0.0420 (7)
O21	0.58052 (15)	0.3899 (2)	0.15759 (8)	0.0585 (5)
N21	0.55915 (19)	0.2731 (3)	0.49254 (9)	0.0518 (6)
C21	0.6347 (2)	0.3454 (3)	0.38489 (12)	0.0358 (6)
C22	0.5404 (2)	0.2945 (4)	0.42231 (12)	0.0530 (8)
H22	0.4564	0.2731	0.3965	0.064*
C23	0.6812 (3)	0.3037 (3)	0.52792 (12)	0.0531 (8)
H23	0.6983	0.2881	0.5769	0.064*
C24	0.7814 (3)	0.3563 (4)	0.49643 (13)	0.0587 (8)
H24	0.8645	0.3776	0.5234	0.070*
C25	0.7582 (2)	0.3775 (3)	0.42381 (12)	0.0483 (7)
H25	0.8257	0.4134	0.4012	0.058*
C26	0.6090 (2)	0.3616 (3)	0.30736 (11)	0.0411 (6)
H26	0.6800	0.3956	0.2872	0.049*
C27	0.4972 (2)	0.3337 (3)	0.26284 (11)	0.0427 (7)
H27	0.4230	0.3021	0.2806	0.051*
C28	0.4874 (2)	0.3515 (4)	0.18536 (12)	0.0424 (7)
N31	0.34719 (17)	0.3318 (3)	0.07380 (9)	0.0453 (6)
H31	0.4123	0.3273	0.0522	0.054*
N32	0.36744 (17)	0.3237 (3)	0.14676 (9)	0.0444 (6)
H32	0.3029	0.3006	0.1675	0.053*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N11	0.0432 (13)	0.0747 (17)	0.0253 (12)	−0.0046 (12)	0.0053 (10)	−0.0020 (11)
O11	0.0460 (11)	0.1105 (16)	0.0332 (10)	0.0188 (11)	0.0133 (9)	0.0091 (10)
C11	0.0333 (14)	0.0401 (17)	0.0273 (13)	0.0005 (13)	0.0028 (11)	0.0012 (13)
C12	0.0343 (14)	0.0670 (19)	0.0302 (15)	−0.0009 (14)	0.0001 (12)	−0.0002 (14)
C13	0.0527 (17)	0.0600 (19)	0.0285 (15)	−0.0008 (15)	−0.0009 (14)	−0.0025 (14)
C14	0.0370 (15)	0.072 (2)	0.0369 (16)	0.0044 (15)	−0.0048 (13)	−0.0054 (15)
C15	0.0364 (14)	0.0619 (19)	0.0368 (15)	0.0035 (14)	0.0048 (12)	−0.0008 (14)
C16	0.0407 (16)	0.0531 (18)	0.0290 (14)	0.0035 (14)	0.0077 (12)	0.0016 (13)
C17	0.0401 (16)	0.063 (2)	0.0272 (15)	0.0043 (14)	0.0106 (13)	−0.0020 (14)
C18	0.0423 (16)	0.0521 (18)	0.0294 (15)	0.0070 (15)	0.0013 (13)	0.0036 (14)
O21	0.0493 (11)	0.0949 (15)	0.0324 (10)	−0.0171 (10)	0.0100 (9)	−0.0033 (9)
N21	0.0501 (14)	0.0791 (17)	0.0243 (12)	−0.0043 (12)	0.0026 (10)	0.0024 (11)
C21	0.0378 (14)	0.0412 (15)	0.0265 (12)	−0.0044 (15)	0.0019 (11)	0.0003 (15)
C22	0.0435 (16)	0.087 (2)	0.0265 (15)	−0.0108 (15)	0.0009 (12)	0.0001 (14)
C23	0.0640 (19)	0.066 (2)	0.0250 (15)	−0.0023 (16)	−0.0008 (14)	−0.0014 (14)
C24	0.0484 (18)	0.083 (2)	0.0397 (18)	−0.0120 (17)	−0.0050 (14)	0.0012 (16)
C25	0.0419 (16)	0.068 (2)	0.0331 (15)	−0.0077 (14)	0.0014 (13)	0.0032 (14)
C26	0.0412 (15)	0.0521 (18)	0.0302 (14)	−0.0066 (14)	0.0070 (12)	−0.0002 (14)
C27	0.0433 (15)	0.0588 (18)	0.0260 (14)	−0.0074 (15)	0.0070 (12)	0.0022 (14)
C28	0.0406 (16)	0.0537 (18)	0.0306 (15)	−0.0060 (15)	0.0015 (13)	−0.0039 (14)
N31	0.0434 (14)	0.0726 (17)	0.0195 (11)	−0.0042 (12)	0.0049 (10)	−0.0004 (11)
N32	0.0432 (13)	0.0687 (17)	0.0200 (11)	−0.0081 (11)	0.0028 (10)	0.0018 (11)

Geometric parameters (Å, º) top

N11—C13	1.332 (3)	N21—C23	1.337 (3)
N11—C12	1.331 (3)	C21—C22	1.373 (3)
O11—C18	1.219 (2)	C21—C25	1.375 (3)
C11—C12	1.380 (3)	C21—C26	1.465 (3)
C11—C15	1.372 (3)	C22—H22	0.9300
C11—C16	1.470 (3)	C23—C24	1.356 (3)
C12—H12	0.9300	C23—H23	0.9300
C13—C14	1.363 (3)	C24—C25	1.377 (3)
C13—H13	0.9300	C24—H24	0.9300
C14—C15	1.378 (3)	C25—H25	0.9300
C14—H14	0.9300	C26—C27	1.319 (3)
C15—H15	0.9300	C26—H26	0.9300
C16—C17	1.308 (3)	C27—C28	1.477 (3)
C16—H16	0.9300	C27—H27	0.9300
C17—C18	1.472 (3)	C28—N32	1.337 (2)
C17—H17	0.9300	N31—N32	1.377 (2)
C18—N31	1.335 (3)	N31—H31	0.8600
O21—C28	1.224 (2)	N32—H32	0.8600
N21—C22	1.333 (3)

C13—N11—C12	116.1 (2)	C25—C21—C26	120.4 (2)
C12—C11—C15	116.4 (2)	N21—C22—C21	125.5 (2)
C12—C11—C16	122.7 (2)	N21—C22—H22	117.3
C15—C11—C16	120.9 (2)	C21—C22—H22	117.3
C11—C12—N11	125.4 (2)	C24—C23—N21	123.7 (2)
C11—C12—H12	117.3	C24—C23—H23	118.1
N11—C12—H12	117.3	N21—C23—H23	118.1
N11—C13—C14	123.6 (2)	C23—C24—C25	118.9 (2)
N11—C13—H13	118.2	C23—C24—H24	120.6
C14—C13—H13	118.2	C25—C24—H24	120.6
C13—C14—C15	118.7 (2)	C24—C25—C21	119.6 (2)
C13—C14—H14	120.6	C24—C25—H25	120.2
C15—C14—H14	120.6	C21—C25—H25	120.2
C11—C15—C14	119.8 (2)	C27—C26—C21	127.6 (2)
C11—C15—H15	120.1	C27—C26—H26	116.2
C14—C15—H15	120.1	C21—C26—H26	116.2
C17—C16—C11	127.8 (2)	C26—C27—C28	121.3 (2)
C17—C16—H16	116.1	C26—C27—H27	119.3
C11—C16—H16	116.1	C28—C27—H27	119.3
C16—C17—C18	121.6 (2)	O21—C28—N32	121.6 (2)
C16—C17—H17	119.2	O21—C28—C27	123.5 (2)
C18—C17—H17	119.2	N32—C28—C27	114.9 (2)
O11—C18—N31	121.4 (2)	C18—N31—N32	118.88 (19)
O11—C18—C17	123.9 (2)	C18—N31—H31	120.6
N31—C18—C17	114.7 (2)	N32—N31—H31	120.6
C22—N21—C23	115.7 (2)	C28—N32—N31	120.01 (19)
C22—C21—C25	116.6 (2)	C28—N32—H32	120.0
C22—C21—C26	123.0 (2)	N31—N32—H32	120.0

C15—C11—C12—N11	−2.1 (4)	C22—N21—C23—C24	1.0 (4)
C16—C11—C12—N11	176.8 (2)	N21—C23—C24—C25	−0.9 (4)
C13—N11—C12—C11	0.4 (4)	C23—C24—C25—C21	0.0 (4)
C12—N11—C13—C14	1.3 (4)	C22—C21—C25—C24	0.5 (4)
N11—C13—C14—C15	−1.2 (4)	C26—C21—C25—C24	−178.1 (3)
C12—C11—C15—C14	2.1 (4)	C22—C21—C26—C27	0.7 (4)
C16—C11—C15—C14	−176.8 (3)	C25—C21—C26—C27	179.3 (3)
C13—C14—C15—C11	−0.6 (4)	C21—C26—C27—C28	−178.6 (2)
C12—C11—C16—C17	−1.0 (4)	C26—C27—C28—O21	1.1 (4)
C15—C11—C16—C17	177.9 (3)	C26—C27—C28—N32	−178.5 (2)
C11—C16—C17—C18	−177.0 (3)	O11—C18—N31—N32	1.2 (4)
C16—C17—C18—O11	0.2 (4)	C17—C18—N31—N32	−177.4 (2)
C16—C17—C18—N31	178.7 (3)	O21—C28—N32—N31	2.2 (4)
C23—N21—C22—C21	−0.4 (4)	C27—C28—N32—N31	−178.3 (2)
C25—C21—C22—N21	−0.4 (4)	C18—N31—N32—C28	−164.7 (2)
C26—C21—C22—N21	178.2 (2)

(3b) top

Crystal data top

C₁₈H₁₈N₄O₂	F(000) = 1360
M_r = 322.36	D_x = 1.295 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 34.566 (5) Å	Cell parameters from 2951 reflections
b = 9.3338 (13) Å	θ = 2.3–25.5°
c = 10.4191 (15) Å	µ = 0.09 mm⁻¹
β = 100.401 (4)°	T = 293 K
V = 3306.3 (8) Å³	Block, white
Z = 8	0.28 × 0.18 × 0.16 mm

Data collection top

Bruker CCD APEX-2 diffractometer	2951 independent reflections
Radiation source: fine-focus sealed tube	2171 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
?hemisphere scans	θ_max = 25.5°, θ_min = 2.3°
Absorption correction: empirical (using intensity measurements) sadabs	h = −41→41
T_min = 0.981, T_max = 0.986	k = −11→11
18928 measured reflections	l = −12→12

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.059	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.189	H atoms treated by a mixture of independent and constrained refinement
S = 1.37	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
2951 reflections	(Δ/σ)_max = 0.001
217 parameters	Δρ_max = 0.61 e Å⁻³
1 restraint	Δρ_min = −0.36 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
N11A	0.31441 (6)	−0.0114 (2)	1.0199 (2)	0.0647 (6)
O11A	0.44538 (4)	−0.19593 (16)	0.69020 (16)	0.0613 (5)
C18A	0.44102 (6)	−0.0652 (2)	0.67487 (19)	0.0451 (5)
C11A	0.36627 (6)	0.0228 (2)	0.89571 (19)	0.0434 (5)
C12A	0.33994 (7)	−0.0604 (2)	0.9495 (2)	0.0550 (6)
H12A	0.3402	−0.1587	0.9349	0.066*
C13A	0.31418 (7)	0.1301 (3)	1.0385 (2)	0.0649 (7)
H13A	0.2963	0.1678	1.0863	0.078*
C14A	0.33891 (7)	0.2226 (3)	0.9907 (2)	0.0626 (6)
H14A	0.3376	0.3206	1.0057	0.075*
C15A	0.36557 (7)	0.1689 (2)	0.9207 (2)	0.0548 (6)
H15A	0.3831	0.2300	0.8901	0.066*
C16A	0.39322 (6)	−0.0453 (2)	0.82159 (19)	0.0472 (5)
H16A	0.3959	−0.1441	0.8303	0.057*
C17A	0.41437 (6)	0.0175 (2)	0.74317 (19)	0.0459 (5)
H17A	0.4124	0.1161	0.7308	0.055*
N21A	0.46086 (5)	0.01019 (19)	0.59961 (17)	0.0486 (5)
H21A	0.4576	0.1015	0.5944	0.058*
C21A	0.48780 (6)	−0.0566 (2)	0.5263 (2)	0.0479 (5)
H21B	0.4731	−0.1112	0.4544	0.057*
H21C	0.5050	−0.1220	0.5822	0.057*
O11B	0.43663 (6)	0.30857 (18)	0.5644 (3)	0.1003 (8)
N11B	0.30135 (7)	0.6023 (2)	0.8397 (2)	0.0778 (7)
C11B	0.33301 (6)	0.4462 (2)	0.7052 (2)	0.0485 (5)
C12B	0.33255 (7)	0.5606 (2)	0.7899 (2)	0.0600 (6)
H12B	0.3557	0.6122	0.8140	0.072*
C13B	0.26835 (9)	0.5246 (3)	0.8044 (3)	0.0779 (8)
H13B	0.2461	0.5511	0.8373	0.093*
C14B	0.26574 (7)	0.4097 (3)	0.7236 (3)	0.0703 (7)
H14B	0.2423	0.3588	0.7030	0.084*
C15B	0.29828 (7)	0.3690 (3)	0.6722 (2)	0.0600 (6)
H15B	0.2969	0.2909	0.6162	0.072*
C16B	0.36815 (7)	0.4066 (2)	0.6540 (2)	0.0533 (6)
H16B	0.3680	0.3164	0.6160	0.064*
C17B	0.40034 (7)	0.4853 (2)	0.6556 (2)	0.0565 (6)
H17B	0.4014	0.5765	0.6922	0.068*
C18B	0.43419 (8)	0.4332 (2)	0.6018 (3)	0.0711 (8)
N21B	0.46228 (9)	0.5326 (2)	0.5998 (3)	0.1142 (13)
H21D	0.4572	0.6200	0.6168	0.137*
C21B	0.50362 (11)	0.4970 (4)	0.5684 (3)	0.0928 (10)
H21E	0.5231	0.5674	0.6058	0.111*
H21F	0.5124	0.4024	0.5996	0.111*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N11A	0.0653 (13)	0.0662 (13)	0.0707 (13)	−0.0114 (10)	0.0334 (11)	−0.0077 (9)
O11A	0.0662 (10)	0.0444 (9)	0.0815 (11)	0.0039 (7)	0.0352 (8)	0.0022 (7)
C18A	0.0437 (11)	0.0449 (12)	0.0483 (11)	−0.0013 (9)	0.0126 (9)	−0.0042 (8)
C11A	0.0444 (11)	0.0460 (11)	0.0424 (10)	−0.0023 (8)	0.0144 (9)	0.0012 (8)
C12A	0.0596 (13)	0.0455 (13)	0.0653 (14)	−0.0089 (10)	0.0259 (11)	−0.0020 (10)
C13A	0.0634 (14)	0.0697 (17)	0.0687 (14)	0.0010 (12)	0.0313 (12)	−0.0101 (12)
C14A	0.0810 (16)	0.0478 (13)	0.0654 (14)	0.0025 (11)	0.0304 (12)	−0.0071 (10)
C15A	0.0690 (14)	0.0466 (12)	0.0547 (12)	−0.0069 (10)	0.0269 (11)	−0.0007 (9)
C16A	0.0481 (11)	0.0421 (11)	0.0533 (12)	−0.0004 (9)	0.0144 (10)	−0.0025 (8)
C17A	0.0485 (12)	0.0415 (11)	0.0510 (12)	−0.0008 (8)	0.0178 (10)	−0.0038 (8)
N21A	0.0489 (10)	0.0439 (10)	0.0578 (10)	0.0028 (7)	0.0228 (9)	−0.0008 (7)
C21A	0.0446 (11)	0.0468 (12)	0.0556 (12)	0.0022 (9)	0.0181 (10)	−0.0012 (9)
O11B	0.1115 (15)	0.0418 (10)	0.175 (2)	0.0043 (9)	0.1007 (16)	−0.0059 (10)
N11B	0.0761 (14)	0.0602 (13)	0.1127 (17)	−0.0122 (11)	0.0588 (13)	−0.0232 (12)
C11B	0.0539 (13)	0.0417 (11)	0.0543 (12)	−0.0010 (9)	0.0219 (10)	0.0027 (9)
C12B	0.0570 (13)	0.0536 (13)	0.0789 (15)	−0.0106 (10)	0.0378 (12)	−0.0114 (11)
C13B	0.0631 (16)	0.0620 (16)	0.120 (2)	0.0040 (12)	0.0459 (16)	0.0012 (15)
C14B	0.0487 (13)	0.0723 (17)	0.0942 (19)	−0.0075 (11)	0.0242 (12)	0.0007 (14)
C15B	0.0584 (13)	0.0564 (14)	0.0690 (14)	−0.0092 (10)	0.0221 (11)	−0.0061 (11)
C16B	0.0631 (13)	0.0402 (11)	0.0643 (13)	0.0018 (10)	0.0321 (11)	−0.0010 (9)
C17B	0.0632 (15)	0.0397 (11)	0.0742 (15)	0.0033 (10)	0.0334 (12)	−0.0006 (10)
C18B	0.0785 (17)	0.0392 (13)	0.113 (2)	0.0072 (11)	0.0629 (16)	0.0028 (12)
N21B	0.134 (2)	0.0412 (12)	0.204 (3)	−0.0017 (13)	0.127 (3)	−0.0050 (15)
C21B	0.0856 (19)	0.0746 (18)	0.122 (3)	0.0015 (15)	0.029 (2)	0.0052 (19)

Geometric parameters (Å, º) top

N11A—C13A	1.335 (3)	O11B—C18B	1.235 (3)
N11A—C12A	1.327 (3)	N11B—C12B	1.336 (3)
O11A—C18A	1.236 (2)	N11B—C13B	1.346 (4)
C18A—N21A	1.332 (2)	C11B—C12B	1.388 (3)
C18A—C17A	1.479 (3)	C11B—C15B	1.389 (3)
C11A—C12A	1.389 (3)	C11B—C16B	1.460 (3)
C11A—C15A	1.389 (3)	C13B—C14B	1.357 (4)
C11A—C16A	1.459 (3)	C14B—C15B	1.383 (3)
C13A—C14A	1.370 (3)	C16B—C17B	1.331 (3)
C14A—C15A	1.369 (3)	C17B—C18B	1.469 (3)
C16A—C17A	1.327 (3)	C18B—N21B	1.346 (3)
N21A—C21A	1.448 (2)	N21B—C21B	1.559 (4)
C21A—C21Aⁱ	1.514 (4)	C21B—C21Bⁱⁱ	1.402 (7)

C13A—N11A—C12A	116.32 (19)	C12B—N11B—C13B	116.2 (2)
O11A—C18A—N21A	122.24 (18)	C12B—C11B—C15B	116.6 (2)
O11A—C18A—C17A	121.68 (18)	C12B—C11B—C16B	122.2 (2)
N21A—C18A—C17A	116.04 (18)	C15B—C11B—C16B	121.2 (2)
C12A—C11A—C15A	116.01 (19)	N11B—C12B—C11B	125.0 (2)
C12A—C11A—C16A	119.82 (18)	N11B—C13B—C14B	123.6 (2)
C15A—C11A—C16A	124.15 (18)	C15B—C14B—C13B	119.3 (2)
N11A—C12A—C11A	125.4 (2)	C14B—C15B—C11B	119.3 (2)
N11A—C13A—C14A	123.4 (2)	C17B—C16B—C11B	127.2 (2)
C13A—C14A—C15A	119.1 (2)	C16B—C17B—C18B	122.3 (2)
C14A—C15A—C11A	119.7 (2)	O11B—C18B—N21B	123.6 (2)
C17A—C16A—C11A	127.51 (19)	O11B—C18B—C17B	122.5 (2)
C16A—C17A—C18A	121.71 (19)	N21B—C18B—C17B	113.8 (2)
C18A—N21A—C21A	122.14 (17)	C18B—N21B—C21B	123.2 (2)
N21A—C21A—C21Aⁱ	110.1 (2)	C21Bⁱⁱ—C21B—N21B	101.7 (4)

Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1, −y+1, −z+1.

(4b) top

Crystal data top

C₁₈H₁₈N₄O₂	F(000) = 340
M_r = 322.36	D_x = 1.321 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 4.7967 (15) Å	Cell parameters from 1377 reflections
b = 11.547 (4) Å	θ = 2.3–25.0°
c = 14.726 (5) Å	µ = 0.09 mm⁻¹
β = 96.451 (10)°	T = 293 K
V = 810.5 (4) Å³	Block, white
Z = 2	0.26 × 0.13 × 0.11 mm

Data collection top

Bruker CCD APEX-2 diffractometer	1377 independent reflections
Radiation source: fine-focus sealed tube	478 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.242
hemisphere scans	θ_max = 25.0°, θ_min = 2.3°
Absorption correction: empirical (using intensity measurements) sadabs	h = −5→5
T_min = 0.986, T_max = 0.990	k = −13→13
9068 measured reflections	l = −17→15

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.065	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.140	H atoms treated by a mixture of independent and constrained refinement
S = 0.90	w = 1/[σ²(F_o²) + (0.050P)²] where P = (F_o² + 2F_c²)/3
1377 reflections	(Δ/σ)_max < 0.001
109 parameters	Δρ_max = 0.26 e Å⁻³
0 restraints	Δρ_min = −0.19 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O11	0.2469 (6)	0.2568 (3)	−0.0331 (2)	0.0628 (10)
N11	−0.6676 (8)	0.5082 (3)	0.2638 (3)	0.0547 (12)
C11	−0.5401 (10)	0.4068 (4)	0.2855 (3)	0.0541 (13)
H11	−0.5786	0.3703	0.3389	0.065*
C12	−0.3559 (9)	0.3533 (4)	0.2335 (3)	0.0475 (13)
H12	−0.2726	0.2833	0.2525	0.057*
C13	−0.2948 (9)	0.4052 (4)	0.1519 (3)	0.0369 (12)
C15	−0.6103 (10)	0.5564 (4)	0.1858 (4)	0.0573 (15)
H15	−0.6980	0.6259	0.1682	0.069*
C14	−0.4283 (9)	0.5090 (4)	0.1295 (3)	0.0482 (14)
H14	−0.3955	0.5473	0.0762	0.058*
C16	−0.1074 (9)	0.3535 (4)	0.0912 (3)	0.0479 (13)
H16	−0.0927	0.3910	0.0361	0.058*
C17	0.0426 (9)	0.2584 (4)	0.1078 (3)	0.0397 (12)
H17	0.0319	0.2193	0.1625	0.048*
C18	0.2286 (9)	0.2117 (4)	0.0419 (3)	0.0416 (12)
N21	0.3717 (7)	0.1165 (3)	0.0723 (2)	0.0450 (10)
H21	0.3499	0.0906	0.1258	0.054*
C21	0.5613 (9)	0.0558 (3)	0.0185 (3)	0.0472 (14)
H21A	0.7362	0.0403	0.0563	0.057*
H21B	0.6028	0.1047	−0.0318	0.057*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O11	0.081 (3)	0.058 (2)	0.054 (2)	0.0046 (19)	0.028 (2)	0.0084 (18)
N11	0.059 (3)	0.050 (3)	0.056 (3)	0.001 (2)	0.011 (3)	−0.011 (2)
C11	0.056 (3)	0.062 (3)	0.046 (3)	−0.002 (3)	0.014 (3)	0.001 (3)
C12	0.042 (3)	0.045 (3)	0.058 (3)	0.008 (2)	0.017 (3)	0.002 (3)
C13	0.035 (3)	0.037 (3)	0.039 (3)	−0.007 (2)	0.006 (2)	−0.004 (2)
C15	0.057 (4)	0.042 (3)	0.074 (4)	0.009 (3)	0.017 (3)	−0.003 (3)
C14	0.061 (4)	0.042 (3)	0.042 (3)	0.009 (3)	0.007 (3)	0.001 (2)
C16	0.056 (3)	0.047 (3)	0.043 (3)	−0.005 (3)	0.016 (3)	−0.004 (2)
C17	0.052 (3)	0.032 (3)	0.039 (3)	−0.001 (2)	0.021 (3)	−0.006 (2)
C18	0.044 (3)	0.039 (3)	0.045 (3)	−0.010 (3)	0.018 (3)	−0.006 (2)
N21	0.049 (3)	0.040 (2)	0.052 (2)	0.005 (2)	0.030 (2)	0.000 (2)
C21	0.041 (3)	0.042 (3)	0.063 (3)	0.001 (2)	0.022 (3)	−0.004 (2)

Geometric parameters (Å, º) top

O11—C18	1.232 (5)	C15—C14	1.382 (5)
N11—C15	1.332 (5)	C16—C17	1.320 (5)
N11—C11	1.342 (5)	C17—C18	1.492 (5)
C11—C12	1.378 (5)	C18—N21	1.345 (5)
C12—C13	1.403 (5)	N21—C21	1.452 (5)
C13—C14	1.382 (5)	C21—C21ⁱ	1.494 (7)
C13—C16	1.463 (5)

C15—N11—C11	115.9 (4)	C17—C16—C13	125.8 (4)
N11—C11—C12	124.2 (4)	C16—C17—C18	122.3 (4)
C13—C12—C11	119.5 (4)	O11—C18—N21	123.9 (4)
C14—C13—C12	116.0 (4)	O11—C18—C17	122.5 (4)
C14—C13—C16	120.5 (4)	N21—C18—C17	113.5 (4)
C12—C13—C16	123.4 (4)	C18—N21—C21	122.7 (4)
N11—C15—C14	123.9 (4)	N21—C21—C21ⁱ	111.7 (4)
C13—C14—C15	120.5 (4)

Symmetry code: (i) −x+1, −y, −z.

(4c) top

Crystal data top

C₂₀H₂₂N₄O₂·2(H₂O)	Z = 2
M_r = 386.45	F(000) = 412
Monoclinic, P2₁/c	D_x = 1.326 Mg m⁻³
a = 12.78 (2) Å	Mo Kα radiation, λ = 0.71073 Å
b = 4.681 (9) Å	µ = 0.09 mm⁻¹
c = 16.21 (3) Å	T = 100 K
β = 93.42 (3)°	Needles, light brown
V = 968 (3) Å³	0.16 × 0.15 × 0.10 mm

Data collection top

Bruker CCD APEX-2 diffractometer	1533 independent reflections
Radiation source: fine-focus sealed tube	829 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.170
Hemisphere scans	θ_max = 25.0°, θ_min = 1.6°
Absorption correction: empirical (using intensity measurements) sadabs	h = −10→14
T_min = 0.985, T_max = 0.991	k = −5→5
2184 measured reflections	l = −19→6

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.085	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.224	H atoms treated by a mixture of independent and constrained refinement
S = 0.95	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
1533 reflections	(Δ/σ)_max = 0.061
133 parameters	Δρ_max = 0.32 e Å⁻³
0 restraints	Δρ_min = −0.41 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O11	0.2085 (2)	0.1741 (8)	0.90035 (18)	0.0307 (9)
N11	−0.2870 (3)	0.8264 (9)	0.8396 (2)	0.0323 (11)
C22	0.4442 (3)	0.5477 (11)	0.9989 (3)	0.0275 (12)
H22A	0.4416	0.7462	1.0158	0.033*
H22B	0.4070	0.4357	1.0381	0.033*
N21	0.2831 (3)	0.6104 (8)	0.9104 (2)	0.0251 (10)
H21	0.2713	0.7910	0.9128	0.030*
O1W	−0.4900 (3)	1.0206 (8)	0.7952 (2)	0.0329 (10)
H2W	−0.437 (4)	0.970 (13)	0.797 (4)	0.050*
H1W	−0.514 (4)	1.199 (13)	0.768 (3)	0.050*
C12	−0.1199 (4)	0.7891 (10)	0.9105 (3)	0.0261 (12)
H12	−0.0744	0.8515	0.9537	0.031*
C17	0.0995 (4)	0.5784 (11)	0.8974 (3)	0.0263 (12)
H17	0.0945	0.7648	0.9166	0.032*
C18	0.2016 (4)	0.4377 (11)	0.9033 (3)	0.0243 (12)
C14	−0.1617 (4)	0.4945 (11)	0.7965 (3)	0.0309 (13)
H14	−0.1450	0.3518	0.7596	0.037*
C15	−0.2576 (4)	0.6183 (11)	0.7896 (3)	0.0341 (14)
H15	−0.3052	0.5554	0.7479	0.041*
C13	−0.0889 (4)	0.5777 (10)	0.8575 (3)	0.0261 (12)
C16	0.0136 (4)	0.4516 (10)	0.8659 (3)	0.0264 (12)
H16	0.0203	0.2645	0.8475	0.032*
C21	0.3900 (4)	0.5166 (10)	0.9143 (3)	0.0266 (12)
H21A	0.4282	0.6261	0.8751	0.032*
H21B	0.3922	0.3175	0.8979	0.032*
C11	−0.2168 (4)	0.9043 (11)	0.8991 (3)	0.0322 (14)
H11	−0.2354	1.0474	0.9352	0.039*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O11	0.031 (2)	0.033 (2)	0.0289 (18)	0.0015 (17)	0.0039 (15)	−0.0016 (15)
N11	0.030 (3)	0.040 (3)	0.027 (2)	0.001 (2)	0.002 (2)	0.004 (2)
C22	0.023 (3)	0.035 (3)	0.025 (3)	−0.003 (2)	0.003 (2)	0.003 (2)
N21	0.024 (3)	0.024 (2)	0.027 (2)	0.0002 (19)	0.0027 (18)	−0.0011 (17)
O1W	0.031 (2)	0.035 (2)	0.0335 (19)	0.0052 (19)	0.0044 (19)	0.0010 (17)
C12	0.020 (3)	0.032 (3)	0.027 (3)	−0.003 (2)	0.004 (2)	0.003 (2)
C17	0.027 (3)	0.030 (3)	0.023 (3)	0.001 (2)	0.003 (2)	0.001 (2)
C18	0.033 (3)	0.024 (3)	0.016 (2)	0.003 (2)	0.004 (2)	0.001 (2)
C14	0.026 (3)	0.039 (3)	0.029 (3)	−0.001 (3)	0.004 (2)	−0.003 (2)
C15	0.032 (3)	0.044 (3)	0.026 (3)	−0.005 (3)	0.000 (2)	0.002 (2)
C13	0.022 (3)	0.033 (3)	0.023 (3)	0.002 (2)	0.002 (2)	0.006 (2)
C16	0.027 (3)	0.031 (3)	0.022 (2)	0.002 (2)	0.005 (2)	0.002 (2)
C21	0.021 (3)	0.031 (3)	0.028 (3)	0.000 (2)	0.002 (2)	0.000 (2)
C11	0.030 (3)	0.041 (3)	0.026 (3)	0.003 (3)	0.004 (2)	0.000 (2)

Geometric parameters (Å, º) top

O11—C18	1.238 (6)	C12—C11	1.354 (6)
N11—C11	1.328 (6)	C12—C13	1.384 (7)
N11—C15	1.335 (6)	C17—C16	1.323 (6)
C22—C22ⁱ	1.493 (9)	C17—C18	1.460 (7)
C22—C21	1.505 (7)	C14—C15	1.354 (7)
N21—C18	1.318 (6)	C14—C13	1.372 (7)
N21—C21	1.434 (6)	C13—C16	1.437 (7)

C11—N11—C15	116.0 (4)	C15—C14—C13	120.6 (5)
C22ⁱ—C22—C21	112.3 (5)	N11—C15—C14	123.2 (5)
C18—N21—C21	124.2 (4)	C14—C13—C12	116.4 (4)
C11—C12—C13	119.5 (5)	C14—C13—C16	121.8 (5)
C16—C17—C18	122.7 (5)	C12—C13—C16	121.9 (5)
O11—C18—N21	123.9 (5)	C17—C16—C13	125.7 (5)
O11—C18—C17	120.8 (5)	N21—C21—C22	113.3 (4)
N21—C18—C17	115.3 (5)	N11—C11—C12	124.3 (5)

Symmetry code: (i) −x+1, −y+1, −z+2.

(4d) top

Crystal data top

C₂₂H₂₆N₄O₂·2(H₂O)	Z = 2
M_r = 414.50	F(000) = 444
Monoclinic, P2₁/n	D_x = 1.206 Mg m⁻³
a = 7.3720 (7) Å	Mo Kα radiation, λ = 0.71073 Å
b = 4.9035 (4) Å	µ = 0.08 mm⁻¹
c = 31.586 (3) Å	T = 293 K
β = 90.197 (3)°	Plates, brown
V = 1141.78 (18) Å³	0.28 × 0.19 × 0.15 mm

Data collection top

Bruker CCD APEX-2 diffractometer	2105 independent reflections
Radiation source: fine-focus sealed tube	1748 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.027
hemisphere scans	θ_max = 25.5°, θ_min = 2.6°
Absorption correction: empirical (using intensity measurements) sadabs	h = −8→8
T_min = 0.981, T_max = 0.987	k = −5→5
13027 measured reflections	l = −36→38

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.060	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.208	H atoms treated by a mixture of independent and constrained refinement
S = 1.60	w = 1/[σ²(F_o²) + (0.1P)²] where P = (F_o² + 2F_c²)/3
2105 reflections	(Δ/σ)_max = 0.020
142 parameters	Δρ_max = 0.36 e Å⁻³
0 restraints	Δρ_min = −0.24 e Å⁻³

Special details top

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
O11	0.3873 (2)	1.0864 (3)	0.07507 (6)	0.0657 (5)
N11	−0.3445 (3)	0.6147 (6)	0.20088 (8)	0.0842 (8)
C11	−0.1841 (4)	0.4948 (6)	0.20164 (8)	0.0799 (8)
H11	−0.1676	0.3514	0.2205	0.096*
C12	−0.0405 (4)	0.5663 (5)	0.17670 (8)	0.0661 (7)
H12	0.0690	0.4731	0.1788	0.079*
C13	−0.0607 (3)	0.7799 (5)	0.14825 (7)	0.0519 (6)
C14	−0.2278 (3)	0.9080 (6)	0.14762 (8)	0.0686 (7)
H14	−0.2478	1.0539	0.1294	0.082*
C15	−0.3640 (3)	0.8210 (7)	0.17375 (9)	0.0808 (9)
H15	−0.4753	0.9100	0.1725	0.097*
C16	0.0873 (3)	0.8707 (4)	0.12081 (7)	0.0535 (6)
H16	0.0812	1.0492	0.1110	0.064*
C17	0.2277 (3)	0.7260 (4)	0.10870 (7)	0.0501 (5)
H17	0.2363	0.5452	0.1174	0.060*
C18	0.3727 (3)	0.8402 (4)	0.08175 (6)	0.0468 (5)
N21	0.4887 (2)	0.6588 (3)	0.06527 (6)	0.0506 (5)
H21	0.4732	0.4883	0.0705	0.061*
C21	0.6392 (3)	0.7413 (4)	0.03898 (7)	0.0509 (6)
H21A	0.6994	0.8960	0.0520	0.061*
H21B	0.5929	0.8000	0.0117	0.061*
C22	0.7758 (3)	0.5171 (4)	0.03230 (7)	0.0487 (6)
H22A	0.8231	0.4585	0.0595	0.058*
H22B	0.7164	0.3622	0.0191	0.058*
C23	0.9312 (3)	0.6101 (4)	0.00464 (7)	0.0483 (6)
H23A	0.8823	0.6769	−0.0219	0.058*
H23B	0.9924	0.7611	0.0185	0.058*
O1W	−0.6639 (4)	0.5442 (5)	0.25232 (11)	0.1144 (9)
H1W	−0.702 (4)	0.465 (6)	0.2228 (9)	0.080*
H2W	−0.558 (4)	0.544 (5)	0.2358 (9)	0.080*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O11	0.0687 (10)	0.0350 (8)	0.0937 (12)	0.0026 (7)	0.0263 (9)	0.0084 (7)
N11	0.0753 (15)	0.1052 (19)	0.0724 (15)	−0.0218 (14)	0.0274 (12)	−0.0149 (14)
C11	0.095 (2)	0.0796 (18)	0.0658 (16)	−0.0089 (14)	0.0279 (15)	0.0015 (13)
C12	0.0694 (15)	0.0699 (15)	0.0591 (14)	0.0016 (12)	0.0167 (11)	0.0026 (12)
C13	0.0508 (12)	0.0553 (12)	0.0498 (12)	−0.0030 (9)	0.0090 (9)	−0.0077 (10)
C14	0.0572 (14)	0.0824 (17)	0.0663 (15)	0.0049 (12)	0.0060 (11)	−0.0058 (12)
C15	0.0506 (14)	0.112 (2)	0.0796 (18)	−0.0010 (14)	0.0096 (13)	−0.0187 (18)
C16	0.0550 (12)	0.0475 (12)	0.0581 (13)	−0.0005 (9)	0.0076 (10)	0.0018 (9)
C17	0.0503 (11)	0.0406 (10)	0.0595 (12)	−0.0019 (8)	0.0095 (10)	0.0045 (9)
C18	0.0489 (11)	0.0353 (10)	0.0563 (12)	−0.0003 (8)	0.0068 (9)	0.0037 (8)
N21	0.0515 (10)	0.0320 (9)	0.0684 (11)	−0.0010 (7)	0.0177 (8)	0.0054 (7)
C21	0.0515 (11)	0.0355 (10)	0.0658 (13)	0.0005 (8)	0.0136 (10)	0.0093 (9)
C22	0.0459 (11)	0.0357 (10)	0.0644 (13)	0.0008 (8)	0.0075 (10)	0.0062 (9)
C23	0.0467 (11)	0.0341 (10)	0.0642 (13)	−0.0005 (8)	0.0077 (9)	0.0057 (8)
O1W	0.0776 (14)	0.1009 (17)	0.165 (2)	0.0096 (12)	0.0457 (16)	0.0090 (16)

Geometric parameters (Å, º) top

O11—C18	1.230 (2)	C16—C17	1.313 (3)
N11—C11	1.321 (4)	C17—C18	1.479 (3)
N11—C15	1.333 (4)	C18—N21	1.340 (3)
C11—C12	1.367 (4)	N21—C21	1.446 (3)
C12—C13	1.388 (3)	C21—C22	1.506 (3)
C13—C14	1.383 (3)	C22—C23	1.513 (3)
C13—C16	1.465 (3)	C23—C23ⁱ	1.511 (4)
C14—C15	1.370 (4)

C11—N11—C15	116.3 (2)	C16—C17—C18	122.35 (19)
N11—C11—C12	124.8 (3)	O11—C18—N21	121.91 (18)
C11—C12—C13	119.0 (3)	O11—C18—C17	122.26 (18)
C14—C13—C12	116.5 (2)	N21—C18—C17	115.83 (17)
C14—C13—C16	121.2 (2)	C18—N21—C21	121.95 (16)
C12—C13—C16	122.3 (2)	N21—C21—C22	113.01 (15)
C15—C14—C13	120.3 (3)	C23—C22—C21	111.64 (15)
N11—C15—C14	123.1 (3)	C23ⁱ—C23—C22	114.00 (19)
C17—C16—C13	126.7 (2)

Symmetry code: (i) −x+2, −y+1, −z.

Acknowledgements

We acknowledge DST, New Delhi, India, for financial support, DST-FIST for the single-crystal diffractometer and M. Garai acknowledges IIT Kharagpur for a research fellowship.

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IUCrJ

Volume 2| Part 5| September 2015| Pages 523-533

ISSN: 2052-2525

https://doi.org/10.1107/S2052252515009987

CHEMISTRY | CRYSTENG

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research papers\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Exploration and exploitation of homologous series of bis­(acrylamido)alkanes containing pyridyl and phenyl groups: β-sheet versus two-dimensional layers in solid-state photochemical [2 + 2] reactions

1. Introduction

2. Experimental

2.1. Synthesis of 1a

2.2. Synthesis of 4a

2.3. Crystallographic data and refinement details

3. Results and discussion

3.1. β-sheet and two-dimensional layers with the —HN—NH— spacer

3.2. β-sheet, two-dimensional layers and water inclusion with —HN—(CH2)2—NH— spacer

3.3. N—H⋯O hydrogen-bonded two-dimensional layers and β-sheet with —HN—(CH2)4—NH— spacer

3.4. β-sheets with —HN—(CH2)6—NH— spacer

3.5. Molecular structure versus hydrogen-bonding networks

3.6. Trends in the melting points of the homologues series

3.7. Solid-state reactivities of 1c, 2b, 2c, 3a, 4a, 3c and 4c

4. Conclusions

Supporting information

Acknowledgements

References

research papers

Exploration and exploitation of homologous series of bis(acrylamido)alkanes containing pyridyl and phenyl groups: β-sheet versus two-dimensional layers in solid-state photochemical [2 + 2] reactions

3.2. β-sheet, two-dimensional layers and water inclusion with —HN—(CH₂)₂—NH— spacer

3.3. N—H⋯O hydrogen-bonded two-dimensional layers and β-sheet with —HN—(CH₂)₄—NH— spacer

3.4. β-sheets with —HN—(CH₂)₆—NH— spacer