research communications
Crystal structures, syntheses, and spectroscopic and electrochemical measurements of two push–pull chromophores: 2-[4-(dimethylamino)benzylidene]-1H-indene-1,3(2H)-dione and (E)-2-{3-[4-(dimethylamino)phenyl]allylidene}-1H-indene-1,3(2H)-dione
aDepartment of Chemistry, New Mexico Highlands University, Las Vegas, New Mexico, 87701, USA, and bSchool of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, 30332, USA
*Correspondence e-mail: bogdgv@gmail.com
The title pull–push chromophores, 2-[4-(dimethylamino)benzylidene]-1H-indene-1,3(2H)-dione, C18H15NO2 (ID[1]) and (E)-2-{3-[4-(dimethylamino)phenyl]allylidene}-1H-indene-1,3(2H)-dione, C20H17NO2 (ID[2]), have donor–π-bridge–acceptor structures. The molecule with the short π-bridge, ID[1], is almost planar while for the molecule with a longer bridge, ID[2], is less planar. The benzene ring is inclined to the mean plane of the 2,3-dihydro-1H-indene unit by 3.19 (4)° in ID[1] and 13.06 (8)° in ID[2]. The structures of three polymorphs of compound ID[1] have been reported: the α-polymorph [space group P21/c; Magomedova & Zvonkova (1978). Kristallografiya, 23, 281–288], the β-polymorph [space group P21/c; Magomedova & Zvonkova (1980). Kristallografiya, 25 1183–1187] and the γ-polymorph [space group Pna21; Magomedova, Neigauz, Zvonkova & Novakovskaya (1980). Kristallografiya, 25, 400–402]. The molecular packing in ID[1] studied here is centrosymmetric (space group P21/c) and corresponds to the β-polymorph structure. The molecular packing in ID[2] is non-centrosymmetric (space group P21), which suggests potential NLO properties for this crystalline material. In both compounds, there is short intramolecular C—H⋯O contact present, enclosing an S(7) ring motif. In the crystal of ID[1], molecules are linked by C—H⋯O hydrogen bonds and C—H⋯π interactions, forming layers parallel to the bc plane. In the crystal of ID[2], molecules are liked by C—H⋯O hydrogen bonds to form 21 helices propagating along the b-axis direction. The molecules in the helix are linked by offset π–π interactions with, for example, a centroid–centroid distance of 3.9664 (13) Å (= b axis) separating the indene rings, and an offset of 1.869 Å. Spectroscopic and electrochemical measurements show the ability of these compounds to easily transfer electrons through the π-conjugated chain.
1. Chemical context
Organic molecules containing donor and acceptor groups connected by a conjugated π-bridge (push–pull chromophores) are important in many areas of materials chemistry, especially organic electronics and optoelectronics. Applications of pull–push molecules can be related to their properties such as intramolecular charge transfer and specific molecular arrangements in the solid state. Intramolecular charge transfer from donor to acceptor via a π-bridge defines their colour, light absorption and emission, hyperpolarizability and other optoelectronic effects. Applications of pull–push chromophores include non-linear optics (NLO; Ortiz et al., 1994), as luminescent sensors (Duarte et al., 2011; Qin et al., 2015), solid-state lasers (Samuel & Turnbull, 2007), organic light-emitting diodes (Muller et al., 2003), organic field-effect transistors (Suponitsky et al., 2006; Oliveira et al., 2018) and many more. The spectroscopic properties of pull–push molecules are related to the donor and acceptor strength in these molecules and to the length of the π-bridge. Many such compounds have been studied, but not all of their crystal structures have been reported. Such compounds are important for their NLO properties (Andreu et al., 2003; Raimundo et al., 2002). Herein, we report on the crystal structures, syntheses and spectroscopic and electrochemical properties of the title donor–π-bridge–acceptor structures, ID[1] and ID[2]. The structures of three polymorphs of ID[1] have been reported previously; the α-polymorph (Magomedova & Zvonkova, 1978), the β-polymorph (Magomedova & Zvonkova, 1980) and the γ-polymorph (Magomedova, Neigauz et al., 1980). We have repeated the structural study of ID[1] in order to establish exactly which polymorph we obtained. It was then characterized by spectroscopic and electrochemical measurements.
2. Structural commentary
The molecular structures of ID[1] and ID[2] are illustrated in Fig. 1. The structural analysis of ID[1] synthesized by us established that it is the β-polymorph (Magomedova & Zvonkova, 1980), and it was then characterized with spectroscopic (§4) and electrochemical (§5) measurements.
Both molecules have acceptor–π-bridge–donor structures. It was found, as in our previous studies (Tillotson et al., 2019), that with an increase of the length of the π-conjugated bridge the molecule becomes less planar, and the angles between the different planar fragments (acceptor–bridge, bridge–donor) become larger (Table 1).
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Compound ID[1] has an almost planar structure, with the benzene ring (C10–C15) being inclined to the mean plane of the indene ring system (C1–C9) by 3.19 (4)°. In ID[2] the deviation from planarity is somewhat larger with the benzene ring (C10–C15) being inclined to the mean plane of the indene ring system (C1–C9) by 13.06 (8)°; see further details in Table 1.
3. Supramolecular features
Molecules of ID[1] and ID[2] have significant dipole moments, which is very common for NLO chromophores. Because of this, molecules have a trend to antiparallel packing, which is observed in the crystal structures of both ID[1] and ID[2].
In the crystal of ID[1], molecules form two almost perpendicular stacks with anangle of ca 84.47° between them. The molecules, which stack in an antiparallel or head-to-tail fashion, are linked by C—H⋯O hydrogen bonds (Fig. 2, Table 2), forming layers lying parallel to the bc plane. Within the layers there are C—H⋯π interactions present (Table 2).
In the crystal of ID[2], molecules form stacks with parallel molecular positions, and shifted positions of stacks extended along the b-axis direction within the acentric P21. The ID[2] molecules are packed in a herringbone fashion (Fig. 3). Here, the angle between two molecules from different stacks is ca 60.8°. The molecules are linked by C—H⋯O hydrogen bonds (Table 3), forming a 21 helix that propagates along the b-axis direction. The molecules in the helix are linked by offset π–π interactions with, for example, a centroid–centroid distance Cg1⋯Cg1i of 3.9664 (13) Å [symmetry code: (i) x, y − 1, z] separating the indene ring systems (C1–C9), with an offset of 1.869 Å.
4. Spectroscopic studies
Absorbance spectra were obtained for both ID[1] and ID[2] in chloroform and acetonitrile. For donor–acceptor polyenes, the dominating feature of the absorbance spectrum is the π–π* transition that results from charge transfer from donor to acceptor. According to recent studies (Bogdanov et al., 2019), it proves that dimethylaminophenyl polyenals have reversed solvatochromism, which is proved by the maxima of the absorption values (Table 4), showing that both ID[1] and ID[2] have their peaks higher in chloroform than in acetonitrile; see the absorption spectra of ID[1] and ID[2] in acetonitrile given in Fig. 4.
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5. Electrochemical measurements
Donor–acceptor polyenes can be characterized by electrochemical measurements to show their ability to transfer electrons. The voltammagrams (Fig. 5) demonstrate a completely reversible oxidation process and a partially reversible reduction process. When only swept between 0 V and 1.7 V the oxidation process is reversible (Fig. 5a), however, when swept to −1.9 V the reduction is only partly reversible (Fig. 5b). This represents the ability of the compound to `easily' transfer electrons through the chain from donor towards acceptor.
Note: cyclic voltammagrams of ID[1] were made against FeCp2+/0 (internal reference E1/2+/0 = 0.55 V vs Ag/AgCl) in dichloromethane with 0.1 M nBu4NPF6). Measurements were recorded at 50 mV s−1 using a BAS Potentiostat using a glassy carbon Pt wire auxilliary electrode and a Ag/AgCl reference electrode.
6. Database survey
A search of the Cambridge Structural Database (CSD Version 5.40, update May 2019; Groom et al., 2016) for the of ID[1] yielded 27 hits. Three of them, 2-(p-diethylaminobenzylidene)-1,3-indandione (CSD refcode TELWEM; Khodorkovsky et al., 1996), which has ethyl groups instead of methyl groups in the donor, 2-{[4-(diphenylamino)phenyl]methylidene}-1H-indene-1,3(2H)-dione (QENYEQ at 223 K: Hariharan et al., 2018; QENYEQ01 at 150 K: Redon et al., 2018), which has methyl groups in the donor, and 2-{[4-(dibutylamino)phenyl]methylidene}-1H-indene-1,3(2H)-dione (BIQYUY; Situ et al., 2019), which has butyl groups in the donor. In these three compounds, the benzene ring is inclined to the mean plane of the 2,3-dihydro-1H-indene ring system by 7.6 (2), 1.66 (6)/1.49 (9) and 5.71 (9)°, for TELWEN, QENYEQ/QENYEQ01 and BIQYUY, respectively, compared to 3.19 (4)° in ID[1].
Also, out of all 27 hits there are three hits, (MBYINO: Magomedova et al., 1978; MBYINO01: Magomedova, Neigauz et al., 1980; MBYINO02: Magomedova & Zvonkova, 1980), which are the α, γ and β ID[1] polymorphs, respectively, published over 40 years ago. It should be mentioned that the crystal packing in the α and β polymorphs is centric (space group P21/c), while in the γ polymorph it is acentric (space group Pna21). The of ID[1] we obtained corresponds to the β polymorph, i.e. the centrosymmetric modification MBYINO02. The dihedral angles between the benzene and indene rings for two independent molecules in MBYINO are ca 4.35 and 7.79°, compared to ca 7.36° in MBYINO01, and 3.54° in MBYINO02 (cf. 3.19 (4)° in the present analysis of ID[1]).
A search of the CSD for the H-indene-1,3(2H)-dione (ZIGPIR; Solanke et al., 2018), has a triple bond between atoms C18 and C19. The second, 2-[4-(dimethylamino)cinnamoyl]indan-1,3-dione (CNINDO; Magomedova, Zvonkova et al., 1980) has a hydroxyl group attached to atom C18. Like ID[2], it crystallizes in the chiral monoclinic P21. The benzene ring is inclined to the mean plane of the indene ring system by ca 11.42° in CNINDO compared to 13.06 (8)° in ID[2]. In ZIGPIR this dihedral angle is smaller at 8.6 (3)°.
of ID[2] yielded nine hits. Only two structures are similar to that of ID[2]. The first, 2-{3-[4-(dimethylamino)phenyl]prop-2-yn-1-ylidene}-17. Synthesis and crystallization
For the synthesis of the title compounds, two et al., 2019). 2,3-Indanedione was purchased from Aldrich and used without further purification.
were used: 4-(dimethylamino)benzaldehyde (A1; purchased from Aldrich) and 4-(dimethylamino)cinnamaldehyde (A2), which was synthesized as described previously (Tillotson,Synthesis of 2-[4-(dimethylamino)benzylidene]indane-1,3-dione (ID[1]): Aldehyde A1 (2.00 g, 13.4 mmol) and 1,3-indanedione (2.01 g, 13.4 mmol) were suspended in 100 ml of absolute ethanol. The mixture was gently heated until the solids had dissolved. After about 10 min of stirring the dissolution was complete, and a red crystalline precipitate began forming on the walls of the flask. The reaction mixture was stirred vigorously overnight, and the resulting product was collected by filtration then washed with cold ethanol and hexanes to give shiny dark-red crystals (yield 3.65 g, 98%; m.p. 477–478 K). ID[1] can be purified by recrystallization using numerous solvent systems (acetone, ethanol, ethyl acetate/hexane, dichloromethane/hexane and toluene (to name a few), many of which afforded single crystals. 1H NMR (400 MHz, CD2Cl2) δ 8.52 (d, J = 9.16 Hz, 2H), 7.91–9.73 (m, 4H), 7.71 (s, 1H), 6.77 (d, J = 9.16 HZ, 2H), 3.14 (s, 6H) ppm. 13C NMR (100 MHz, CD2Cl2) δ 191.6, 190.1, 154.5, 147.3, 142.7, 140.3, 138.2, 134.8, 134.5, 123.3, 122.7, 122.6, 122.2, 111.7, 40.3 ppm.
Synthesis of (E)-2-{3-[4-(dimethylamino)phenyl]allylidene}indane-1,3-dione (ID[2]): Aldehyde A2 (1.00 g, 5.71 mmol), 1,3-indanedione (0.85 g, 5.7 mmol) and piperidine (0.15 ml, 1.4 mmol) in ethanol (50 ml) were mixed and treated as for the synthesis of ID[1]. The crude product obtained was collected by filtration and washed with cold ethanol before being recrystallized from ethanol to give incredibly shiny and thin purple actinic crystals (1.55 g, 90%; m.p. 535–537 K). They were washed with hexane and dried under vacuum. 1H NMR (400 MHz, CD2Cl2) δ 8.25 (dd, J = 15.0, 12.2 Hz, 1H), 7.90–7.86 (m, 2H), 7.76–7.73 (m, 2H), 7.60 (d, J = 12.2 Hz, 1H), 7.60 (d, J = 9.0 Hz, 2H), 7.34 (d, J = 15.0 Hz, 1H), 6.72 (d, J = 9.0 Hz, 2H), 3.08 (s, 6H) ppm.
8. Refinement
Crystal data, data collection and structure . For both structures, the C-bound hydrogen atoms were positioned geometrically and refined using a riding model: C—H = 0.95–0.98 Å with Uiso(H) = 1.5Ueq(C-methyl) and 1.2Uiso(C) for other H atoms.
details are summarized in Table 5
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Supporting information
https://doi.org/10.1107/S205698901901329X/su5515sup1.cif
contains datablocks ID1, ID2, Gobal. DOI:Structure factors: contains datablock ID1. DOI: https://doi.org/10.1107/S205698901901329X/su5515ID1sup2.hkl
Structure factors: contains datablock ID2. DOI: https://doi.org/10.1107/S205698901901329X/su5515ID2sup3.hkl
Supporting information file. DOI: https://doi.org/10.1107/S205698901901329X/su5515ID1sup4.cml
Supporting information file. DOI: https://doi.org/10.1107/S205698901901329X/su5515ID2sup5.cml
For both structures, data collection: APEX3 (Bruker, 2015); cell
SAINT (Bruker, 2015); data reduction: SAINT (Bruker, 2015); program(s) used to solve structure: SHELXT2017/1 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015b); molecular graphics: Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2018/3 (Sheldrick, 2015b), PLATON (Spek, 2009) and publCIF (Westrip, 2010).C18H15NO2 | F(000) = 584 |
Mr = 277.31 | Dx = 1.333 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
a = 9.2298 (9) Å | Cell parameters from 8518 reflections |
b = 9.0302 (9) Å | θ = 2.2–31.5° |
c = 16.7375 (17) Å | µ = 0.09 mm−1 |
β = 97.863 (1)° | T = 150 K |
V = 1381.9 (2) Å3 | Block, purple |
Z = 4 | 0.40 × 0.20 × 0.15 mm |
Bruker APEXII CCD diffractometer | 3812 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.041 |
φ and ω scans | θmax = 31.8°, θmin = 2.2° |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | h = −13→12 |
Tmin = 0.673, Tmax = 0.746 | k = −12→12 |
15794 measured reflections | l = −23→23 |
4391 independent reflections |
Refinement on F2 | Primary atom site location: dual |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.047 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.139 | H-atom parameters constrained |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0835P)2 + 0.2073P] where P = (Fo2 + 2Fc2)/3 |
4391 reflections | (Δ/σ)max < 0.001 |
192 parameters | Δρmax = 0.27 e Å−3 |
0 restraints | Δρmin = −0.40 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
O3 | 0.93689 (8) | 0.32542 (8) | 0.50819 (4) | 0.03149 (17) | |
O1 | 0.60774 (9) | 0.60246 (9) | 0.32291 (4) | 0.0379 (2) | |
N10 | 0.31173 (9) | 0.97003 (9) | 0.60039 (5) | 0.02873 (18) | |
C13 | 0.60837 (9) | 0.65851 (10) | 0.52818 (5) | 0.02205 (17) | |
C2 | 0.75196 (9) | 0.49196 (9) | 0.44122 (5) | 0.02184 (17) | |
C18 | 0.71343 (9) | 0.55144 (10) | 0.51060 (5) | 0.02284 (17) | |
H18 | 0.769381 | 0.512603 | 0.557817 | 0.027* | |
C4 | 0.89040 (10) | 0.33908 (10) | 0.36262 (5) | 0.02526 (18) | |
C12 | 0.60627 (10) | 0.69512 (10) | 0.61024 (5) | 0.02429 (18) | |
H12 | 0.673418 | 0.647010 | 0.649979 | 0.029* | |
C3 | 0.86960 (9) | 0.37921 (10) | 0.44692 (5) | 0.02369 (18) | |
C11 | 0.51125 (10) | 0.79732 (10) | 0.63494 (5) | 0.02506 (18) | |
H11 | 0.514728 | 0.819276 | 0.690677 | 0.030* | |
C15 | 0.40888 (10) | 0.83354 (10) | 0.49501 (5) | 0.02435 (18) | |
H15 | 0.341038 | 0.880551 | 0.455185 | 0.029* | |
C14 | 0.50520 (10) | 0.73202 (10) | 0.47141 (5) | 0.02373 (18) | |
H14 | 0.502565 | 0.710598 | 0.415658 | 0.028* | |
C10 | 0.40801 (9) | 0.87012 (9) | 0.57750 (5) | 0.02255 (17) | |
C1 | 0.70060 (10) | 0.51650 (10) | 0.35504 (5) | 0.02429 (18) | |
C5 | 0.78862 (10) | 0.41613 (10) | 0.30928 (5) | 0.02495 (18) | |
C6 | 0.78078 (12) | 0.39789 (12) | 0.22630 (6) | 0.0329 (2) | |
H6 | 0.710143 | 0.449691 | 0.190125 | 0.039* | |
C9 | 0.98955 (12) | 0.24303 (13) | 0.33465 (7) | 0.0347 (2) | |
H9 | 1.059397 | 0.190603 | 0.370999 | 0.042* | |
C7 | 0.87982 (14) | 0.30121 (14) | 0.19785 (7) | 0.0392 (3) | |
H7 | 0.876810 | 0.286448 | 0.141453 | 0.047* | |
C17 | 0.31815 (13) | 1.01545 (13) | 0.68433 (7) | 0.0369 (2) | |
H17A | 0.297002 | 0.930205 | 0.717083 | 0.055* | |
H17B | 0.245649 | 1.093342 | 0.688545 | 0.055* | |
H17C | 0.416109 | 1.053349 | 0.703830 | 0.055* | |
C16 | 0.19759 (12) | 1.03450 (12) | 0.54226 (7) | 0.0367 (2) | |
H16A | 0.242318 | 1.089217 | 0.501365 | 0.055* | |
H16B | 0.138187 | 1.102198 | 0.570043 | 0.055* | |
H16C | 0.135358 | 0.955511 | 0.516197 | 0.055* | |
C8 | 0.98325 (14) | 0.22601 (14) | 0.25148 (7) | 0.0409 (3) | |
H8 | 1.050850 | 0.161833 | 0.230903 | 0.049* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O3 | 0.0289 (3) | 0.0367 (4) | 0.0275 (3) | 0.0027 (3) | −0.0011 (3) | 0.0068 (3) |
O1 | 0.0502 (5) | 0.0424 (4) | 0.0201 (3) | 0.0190 (3) | 0.0011 (3) | 0.0033 (3) |
N10 | 0.0287 (4) | 0.0296 (4) | 0.0275 (4) | 0.0028 (3) | 0.0026 (3) | −0.0008 (3) |
C13 | 0.0230 (4) | 0.0253 (4) | 0.0174 (3) | −0.0038 (3) | 0.0009 (3) | 0.0006 (3) |
C2 | 0.0224 (4) | 0.0237 (4) | 0.0190 (4) | −0.0023 (3) | 0.0015 (3) | 0.0023 (3) |
C18 | 0.0233 (4) | 0.0263 (4) | 0.0183 (3) | −0.0032 (3) | 0.0003 (3) | 0.0023 (3) |
C4 | 0.0244 (4) | 0.0261 (4) | 0.0258 (4) | −0.0015 (3) | 0.0052 (3) | 0.0014 (3) |
C12 | 0.0254 (4) | 0.0291 (4) | 0.0174 (3) | −0.0012 (3) | −0.0007 (3) | 0.0010 (3) |
C3 | 0.0214 (4) | 0.0257 (4) | 0.0236 (4) | −0.0035 (3) | 0.0017 (3) | 0.0027 (3) |
C11 | 0.0277 (4) | 0.0288 (4) | 0.0178 (3) | −0.0024 (3) | 0.0003 (3) | −0.0015 (3) |
C15 | 0.0246 (4) | 0.0280 (4) | 0.0194 (4) | −0.0021 (3) | −0.0008 (3) | 0.0034 (3) |
C14 | 0.0253 (4) | 0.0281 (4) | 0.0172 (3) | −0.0032 (3) | 0.0008 (3) | 0.0012 (3) |
C10 | 0.0224 (4) | 0.0221 (4) | 0.0228 (4) | −0.0046 (3) | 0.0017 (3) | 0.0006 (3) |
C1 | 0.0291 (4) | 0.0251 (4) | 0.0187 (4) | 0.0003 (3) | 0.0031 (3) | 0.0013 (3) |
C5 | 0.0277 (4) | 0.0256 (4) | 0.0218 (4) | −0.0005 (3) | 0.0047 (3) | 0.0006 (3) |
C6 | 0.0401 (5) | 0.0365 (5) | 0.0224 (4) | 0.0059 (4) | 0.0056 (4) | 0.0000 (4) |
C9 | 0.0308 (5) | 0.0378 (5) | 0.0363 (5) | 0.0076 (4) | 0.0072 (4) | 0.0026 (4) |
C7 | 0.0470 (6) | 0.0444 (6) | 0.0283 (5) | 0.0076 (5) | 0.0126 (4) | −0.0028 (4) |
C17 | 0.0393 (5) | 0.0389 (5) | 0.0333 (5) | 0.0040 (4) | 0.0079 (4) | −0.0076 (4) |
C16 | 0.0306 (5) | 0.0324 (5) | 0.0449 (6) | 0.0041 (4) | −0.0026 (4) | 0.0035 (4) |
C8 | 0.0427 (6) | 0.0441 (6) | 0.0385 (5) | 0.0122 (5) | 0.0145 (5) | −0.0021 (5) |
O3—C3 | 1.2243 (11) | C15—C14 | 1.3722 (13) |
O1—C1 | 1.2249 (11) | C15—C10 | 1.4207 (12) |
N10—C10 | 1.3578 (12) | C15—H15 | 0.9500 |
N10—C16 | 1.4543 (13) | C14—H14 | 0.9500 |
N10—C17 | 1.4570 (13) | C1—C5 | 1.4961 (13) |
C13—C14 | 1.4152 (12) | C5—C6 | 1.3907 (13) |
C13—C12 | 1.4155 (12) | C6—C7 | 1.3941 (15) |
C13—C18 | 1.4281 (12) | C6—H6 | 0.9500 |
C2—C18 | 1.3700 (12) | C9—C8 | 1.3939 (16) |
C2—C1 | 1.4721 (11) | C9—H9 | 0.9500 |
C2—C3 | 1.4820 (12) | C7—C8 | 1.3941 (17) |
C18—H18 | 0.9500 | C7—H7 | 0.9500 |
C4—C9 | 1.3879 (13) | C17—H17A | 0.9800 |
C4—C5 | 1.3907 (13) | C17—H17B | 0.9800 |
C4—C3 | 1.4943 (13) | C17—H17C | 0.9800 |
C12—C11 | 1.3751 (13) | C16—H16A | 0.9800 |
C12—H12 | 0.9500 | C16—H16B | 0.9800 |
C11—C10 | 1.4190 (12) | C16—H16C | 0.9800 |
C11—H11 | 0.9500 | C8—H8 | 0.9500 |
C10—N10—C16 | 121.29 (9) | C11—C10—C15 | 117.27 (8) |
C10—N10—C17 | 121.15 (8) | O1—C1—C2 | 129.63 (8) |
C16—N10—C17 | 117.56 (9) | O1—C1—C5 | 123.74 (8) |
C14—C13—C12 | 116.40 (8) | C2—C1—C5 | 106.61 (7) |
C14—C13—C18 | 126.35 (8) | C6—C5—C4 | 121.34 (9) |
C12—C13—C18 | 117.25 (8) | C6—C5—C1 | 128.71 (8) |
C18—C2—C1 | 133.27 (8) | C4—C5—C1 | 109.93 (8) |
C18—C2—C3 | 119.19 (8) | C5—C6—C7 | 117.92 (9) |
C1—C2—C3 | 107.54 (7) | C5—C6—H6 | 121.0 |
C2—C18—C13 | 134.62 (8) | C7—C6—H6 | 121.0 |
C2—C18—H18 | 112.7 | C4—C9—C8 | 117.80 (10) |
C13—C18—H18 | 112.7 | C4—C9—H9 | 121.1 |
C9—C4—C5 | 120.99 (9) | C8—C9—H9 | 121.1 |
C9—C4—C3 | 130.22 (9) | C6—C7—C8 | 120.56 (10) |
C5—C4—C3 | 108.79 (8) | C6—C7—H7 | 119.7 |
C11—C12—C13 | 122.85 (8) | C8—C7—H7 | 119.7 |
C11—C12—H12 | 118.6 | N10—C17—H17A | 109.5 |
C13—C12—H12 | 118.6 | N10—C17—H17B | 109.5 |
O3—C3—C2 | 127.57 (8) | H17A—C17—H17B | 109.5 |
O3—C3—C4 | 125.36 (9) | N10—C17—H17C | 109.5 |
C2—C3—C4 | 107.06 (7) | H17A—C17—H17C | 109.5 |
C12—C11—C10 | 120.27 (8) | H17B—C17—H17C | 109.5 |
C12—C11—H11 | 119.9 | N10—C16—H16A | 109.5 |
C10—C11—H11 | 119.9 | N10—C16—H16B | 109.5 |
C14—C15—C10 | 121.68 (8) | H16A—C16—H16B | 109.5 |
C14—C15—H15 | 119.2 | N10—C16—H16C | 109.5 |
C10—C15—H15 | 119.2 | H16A—C16—H16C | 109.5 |
C15—C14—C13 | 121.53 (8) | H16B—C16—H16C | 109.5 |
C15—C14—H14 | 119.2 | C9—C8—C7 | 121.37 (10) |
C13—C14—H14 | 119.2 | C9—C8—H8 | 119.3 |
N10—C10—C11 | 121.43 (8) | C7—C8—H8 | 119.3 |
N10—C10—C15 | 121.31 (8) | ||
C1—C2—C18—C13 | 0.93 (17) | C12—C11—C10—C15 | −0.50 (13) |
C3—C2—C18—C13 | −179.71 (9) | C14—C15—C10—N10 | −179.59 (8) |
C14—C13—C18—C2 | 2.59 (16) | C14—C15—C10—C11 | 0.04 (13) |
C12—C13—C18—C2 | −177.54 (9) | C18—C2—C1—O1 | 1.45 (18) |
C14—C13—C12—C11 | −0.66 (13) | C3—C2—C1—O1 | −177.97 (10) |
C18—C13—C12—C11 | 179.46 (8) | C18—C2—C1—C5 | 179.75 (9) |
C18—C2—C3—O3 | 2.96 (14) | C3—C2—C1—C5 | 0.33 (9) |
C1—C2—C3—O3 | −177.53 (9) | C9—C4—C5—C6 | 1.13 (15) |
C18—C2—C3—C4 | −178.21 (8) | C3—C4—C5—C6 | −178.70 (9) |
C1—C2—C3—C4 | 1.30 (9) | C9—C4—C5—C1 | −177.34 (9) |
C9—C4—C3—O3 | −3.52 (16) | C3—C4—C5—C1 | 2.83 (10) |
C5—C4—C3—O3 | 176.28 (9) | O1—C1—C5—C6 | −1.89 (16) |
C9—C4—C3—C2 | 177.62 (10) | C2—C1—C5—C6 | 179.68 (10) |
C5—C4—C3—C2 | −2.58 (10) | O1—C1—C5—C4 | 176.43 (9) |
C13—C12—C11—C10 | 0.83 (14) | C2—C1—C5—C4 | −2.00 (10) |
C10—C15—C14—C13 | 0.11 (13) | C4—C5—C6—C7 | −0.91 (16) |
C12—C13—C14—C15 | 0.18 (13) | C1—C5—C6—C7 | 177.25 (10) |
C18—C13—C14—C15 | −179.95 (8) | C5—C4—C9—C8 | −0.25 (16) |
C16—N10—C10—C11 | −174.40 (9) | C3—C4—C9—C8 | 179.53 (10) |
C17—N10—C10—C11 | 4.97 (14) | C5—C6—C7—C8 | −0.15 (18) |
C16—N10—C10—C15 | 5.21 (14) | C4—C9—C8—C7 | −0.81 (18) |
C17—N10—C10—C15 | −175.41 (9) | C6—C7—C8—C9 | 1.0 (2) |
C12—C11—C10—N10 | 179.13 (8) |
Cg2 and Cg3 are the centroids of the C4–C9 and C10–C15 rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
C14—H14···O1 | 0.95 | 2.17 | 3.0143 (12) | 147 |
C7—H7···O3i | 0.95 | 2.58 | 3.4813 (14) | 159 |
C11—H11···O1ii | 0.95 | 2.37 | 3.2778 (11) | 160 |
C16—H16A···Cg3iii | 0.98 | 2.91 | 3.7948 (12) | 151 |
C17—H17A···Cg2iv | 0.98 | 2.83 | 3.6591 (13) | 143 |
Symmetry codes: (i) x, −y+1/2, z−1/2; (ii) x, −y+3/2, z+1/2; (iii) −x+1, −y+2, −z+1; (iv) −x+1, −y+1, −z+1. |
C20H17NO2 | F(000) = 320 |
Mr = 303.35 | Dx = 1.350 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
a = 11.072 (2) Å | Cell parameters from 6074 reflections |
b = 3.9664 (8) Å | θ = 2.4–31.6° |
c = 17.557 (4) Å | µ = 0.09 mm−1 |
β = 104.500 (2)° | T = 150 K |
V = 746.5 (3) Å3 | Needle, blue |
Z = 2 | 0.40 × 0.12 × 0.10 mm |
Bruker APEXII CCD diffractometer | 4358 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.044 |
φ and ω scans | θmax = 31.7°, θmin = 1.2° |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | h = −15→16 |
Tmin = 0.584, Tmax = 0.746 | k = −5→5 |
8685 measured reflections | l = −24→25 |
4531 independent reflections |
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)] = 0.044 | H-atom parameters constrained |
wR(F2) = 0.121 | w = 1/[σ2(Fo2) + (0.0488P)2 + 0.2055P] where P = (Fo2 + 2Fc2)/3 |
S = 1.12 | (Δ/σ)max < 0.001 |
4531 reflections | Δρmax = 0.22 e Å−3 |
210 parameters | Δρmin = −0.33 e Å−3 |
1 restraint | Absolute structure: Flack x determined using 1732 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013) |
Primary atom site location: dual | Absolute structure parameter: −0.1 (5) |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
O3 | 0.50946 (14) | 0.2510 (5) | 0.17850 (9) | 0.0331 (4) | |
O1 | 0.11093 (14) | 0.5986 (5) | 0.20367 (9) | 0.0328 (4) | |
N10 | 0.15603 (16) | 0.3906 (5) | 0.69990 (9) | 0.0253 (4) | |
C13 | 0.29025 (17) | 0.2553 (5) | 0.49784 (10) | 0.0203 (3) | |
C10 | 0.20054 (16) | 0.3470 (5) | 0.63500 (10) | 0.0202 (3) | |
C12 | 0.35740 (17) | 0.1388 (5) | 0.57237 (11) | 0.0232 (4) | |
H12 | 0.434333 | 0.025205 | 0.576557 | 0.028* | |
C9 | 0.37083 (18) | 0.5984 (6) | 0.02319 (11) | 0.0250 (4) | |
H9 | 0.450310 | 0.528451 | 0.017745 | 0.030* | |
C11 | 0.31564 (18) | 0.1834 (5) | 0.63920 (11) | 0.0236 (4) | |
H11 | 0.364293 | 0.103946 | 0.688397 | 0.028* | |
C7 | 0.16966 (19) | 0.8643 (6) | −0.03035 (11) | 0.0276 (4) | |
H7 | 0.113386 | 0.972479 | −0.073153 | 0.033* | |
C14 | 0.17745 (18) | 0.4244 (5) | 0.49465 (11) | 0.0224 (4) | |
H14 | 0.130688 | 0.510783 | 0.445647 | 0.027* | |
C19 | 0.29104 (17) | 0.3097 (5) | 0.35537 (11) | 0.0230 (4) | |
H19 | 0.211433 | 0.414940 | 0.342126 | 0.028* | |
C18 | 0.35755 (17) | 0.2675 (5) | 0.29653 (10) | 0.0222 (3) | |
H18 | 0.433577 | 0.144955 | 0.311130 | 0.027* | |
C20 | 0.33964 (17) | 0.2017 (5) | 0.43054 (11) | 0.0222 (4) | |
H20 | 0.414971 | 0.076184 | 0.439446 | 0.027* | |
C17 | 0.2246 (2) | 0.2557 (6) | 0.77578 (11) | 0.0294 (4) | |
H17A | 0.236951 | 0.012715 | 0.770933 | 0.044* | |
H17B | 0.176965 | 0.296073 | 0.815026 | 0.044* | |
H17C | 0.305856 | 0.367609 | 0.792316 | 0.044* | |
C8 | 0.2871 (2) | 0.7601 (6) | −0.03803 (11) | 0.0273 (4) | |
H8 | 0.309669 | 0.800923 | −0.085963 | 0.033* | |
C6 | 0.13502 (17) | 0.8102 (5) | 0.03978 (11) | 0.0247 (4) | |
H6 | 0.056140 | 0.882629 | 0.045770 | 0.030* | |
C16 | 0.03720 (19) | 0.5566 (6) | 0.69463 (13) | 0.0283 (4) | |
H16A | 0.040550 | 0.787428 | 0.675361 | 0.043* | |
H16B | 0.020234 | 0.562374 | 0.746783 | 0.043* | |
H16C | −0.029316 | 0.431904 | 0.658184 | 0.043* | |
C4 | 0.33549 (16) | 0.5416 (5) | 0.09239 (10) | 0.0200 (3) | |
C15 | 0.13295 (17) | 0.4683 (5) | 0.56017 (11) | 0.0224 (4) | |
H15 | 0.055820 | 0.581423 | 0.555547 | 0.027* | |
C3 | 0.40481 (17) | 0.3712 (5) | 0.16627 (10) | 0.0216 (3) | |
C5 | 0.21913 (16) | 0.6474 (5) | 0.10052 (10) | 0.0195 (3) | |
C2 | 0.32319 (17) | 0.3854 (5) | 0.22113 (10) | 0.0212 (3) | |
C1 | 0.20501 (17) | 0.5508 (5) | 0.18022 (11) | 0.0219 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
O3 | 0.0219 (6) | 0.0463 (10) | 0.0311 (7) | 0.0089 (7) | 0.0068 (5) | 0.0039 (7) |
O1 | 0.0235 (6) | 0.0485 (10) | 0.0297 (7) | 0.0070 (7) | 0.0128 (5) | 0.0051 (7) |
N10 | 0.0264 (8) | 0.0304 (9) | 0.0201 (7) | 0.0016 (7) | 0.0078 (6) | 0.0028 (7) |
C13 | 0.0197 (7) | 0.0221 (8) | 0.0182 (7) | −0.0011 (7) | 0.0029 (6) | 0.0026 (6) |
C10 | 0.0196 (7) | 0.0211 (8) | 0.0190 (7) | −0.0023 (7) | 0.0035 (6) | 0.0013 (6) |
C12 | 0.0187 (7) | 0.0278 (9) | 0.0219 (8) | 0.0035 (7) | 0.0028 (6) | 0.0038 (7) |
C9 | 0.0241 (8) | 0.0292 (10) | 0.0240 (8) | −0.0017 (8) | 0.0103 (7) | −0.0015 (7) |
C11 | 0.0214 (8) | 0.0286 (10) | 0.0189 (7) | 0.0020 (7) | 0.0011 (6) | 0.0041 (7) |
C7 | 0.0290 (9) | 0.0305 (10) | 0.0208 (8) | −0.0019 (8) | 0.0017 (7) | 0.0038 (8) |
C14 | 0.0203 (8) | 0.0245 (9) | 0.0198 (7) | −0.0002 (7) | 0.0003 (6) | 0.0041 (7) |
C19 | 0.0212 (8) | 0.0267 (9) | 0.0206 (7) | −0.0009 (7) | 0.0046 (6) | 0.0010 (7) |
C18 | 0.0217 (8) | 0.0237 (9) | 0.0206 (7) | −0.0007 (7) | 0.0038 (6) | −0.0001 (7) |
C20 | 0.0208 (8) | 0.0242 (9) | 0.0213 (8) | −0.0009 (7) | 0.0046 (6) | 0.0008 (7) |
C17 | 0.0351 (10) | 0.0348 (11) | 0.0176 (8) | −0.0032 (9) | 0.0051 (7) | 0.0012 (8) |
C8 | 0.0315 (9) | 0.0313 (10) | 0.0198 (8) | −0.0033 (8) | 0.0076 (7) | 0.0005 (7) |
C6 | 0.0198 (8) | 0.0288 (10) | 0.0243 (8) | −0.0002 (7) | 0.0035 (6) | 0.0026 (7) |
C16 | 0.0257 (9) | 0.0299 (10) | 0.0320 (10) | −0.0005 (8) | 0.0121 (7) | −0.0022 (8) |
C4 | 0.0186 (7) | 0.0222 (8) | 0.0191 (7) | −0.0014 (7) | 0.0047 (6) | −0.0026 (7) |
C15 | 0.0185 (8) | 0.0261 (9) | 0.0206 (8) | 0.0021 (7) | 0.0012 (6) | 0.0032 (7) |
C3 | 0.0187 (7) | 0.0255 (9) | 0.0206 (7) | 0.0003 (7) | 0.0045 (6) | −0.0011 (7) |
C5 | 0.0173 (7) | 0.0221 (8) | 0.0186 (7) | −0.0013 (6) | 0.0037 (6) | −0.0010 (6) |
C2 | 0.0189 (7) | 0.0254 (9) | 0.0190 (7) | 0.0001 (7) | 0.0042 (6) | −0.0007 (7) |
C1 | 0.0195 (7) | 0.0266 (9) | 0.0201 (7) | −0.0001 (7) | 0.0059 (6) | 0.0002 (7) |
O3—C3 | 1.221 (2) | C19—C20 | 1.364 (3) |
O1—C1 | 1.227 (2) | C19—C18 | 1.421 (2) |
N10—C10 | 1.361 (2) | C19—H19 | 0.9500 |
N10—C16 | 1.453 (3) | C18—C2 | 1.365 (3) |
N10—C17 | 1.460 (3) | C18—H18 | 0.9500 |
C13—C14 | 1.406 (3) | C20—H20 | 0.9500 |
C13—C12 | 1.411 (2) | C17—H17A | 0.9800 |
C13—C20 | 1.437 (2) | C17—H17B | 0.9800 |
C10—C11 | 1.416 (3) | C17—H17C | 0.9800 |
C10—C15 | 1.423 (2) | C8—H8 | 0.9500 |
C12—C11 | 1.376 (3) | C6—C5 | 1.387 (3) |
C12—H12 | 0.9500 | C6—H6 | 0.9500 |
C9—C4 | 1.385 (2) | C16—H16A | 0.9800 |
C9—C8 | 1.389 (3) | C16—H16B | 0.9800 |
C9—H9 | 0.9500 | C16—H16C | 0.9800 |
C11—H11 | 0.9500 | C4—C5 | 1.396 (2) |
C7—C6 | 1.395 (3) | C4—C3 | 1.493 (3) |
C7—C8 | 1.402 (3) | C15—H15 | 0.9500 |
C7—H7 | 0.9500 | C3—C2 | 1.478 (2) |
C14—C15 | 1.371 (3) | C5—C1 | 1.496 (2) |
C14—H14 | 0.9500 | C2—C1 | 1.479 (3) |
C10—N10—C16 | 121.07 (16) | H17A—C17—H17B | 109.5 |
C10—N10—C17 | 120.19 (17) | N10—C17—H17C | 109.5 |
C16—N10—C17 | 118.67 (16) | H17A—C17—H17C | 109.5 |
C14—C13—C12 | 116.72 (16) | H17B—C17—H17C | 109.5 |
C14—C13—C20 | 123.71 (16) | C9—C8—C7 | 121.16 (18) |
C12—C13—C20 | 119.57 (17) | C9—C8—H8 | 119.4 |
N10—C10—C11 | 121.65 (16) | C7—C8—H8 | 119.4 |
N10—C10—C15 | 120.86 (17) | C5—C6—C7 | 118.06 (18) |
C11—C10—C15 | 117.49 (16) | C5—C6—H6 | 121.0 |
C11—C12—C13 | 122.48 (17) | C7—C6—H6 | 121.0 |
C11—C12—H12 | 118.8 | N10—C16—H16A | 109.5 |
C13—C12—H12 | 118.8 | N10—C16—H16B | 109.5 |
C4—C9—C8 | 118.26 (18) | H16A—C16—H16B | 109.5 |
C4—C9—H9 | 120.9 | N10—C16—H16C | 109.5 |
C8—C9—H9 | 120.9 | H16A—C16—H16C | 109.5 |
C12—C11—C10 | 120.33 (16) | H16B—C16—H16C | 109.5 |
C12—C11—H11 | 119.8 | C9—C4—C5 | 120.77 (17) |
C10—C11—H11 | 119.8 | C9—C4—C3 | 129.72 (17) |
C6—C7—C8 | 120.39 (18) | C5—C4—C3 | 109.52 (15) |
C6—C7—H7 | 119.8 | C14—C15—C10 | 121.01 (17) |
C8—C7—H7 | 119.8 | C14—C15—H15 | 119.5 |
C15—C14—C13 | 121.95 (17) | C10—C15—H15 | 119.5 |
C15—C14—H14 | 119.0 | O3—C3—C2 | 127.48 (18) |
C13—C14—H14 | 119.0 | O3—C3—C4 | 126.02 (17) |
C20—C19—C18 | 121.06 (18) | C2—C3—C4 | 106.49 (15) |
C20—C19—H19 | 119.5 | C6—C5—C4 | 121.36 (16) |
C18—C19—H19 | 119.5 | C6—C5—C1 | 129.12 (16) |
C2—C18—C19 | 126.54 (18) | C4—C5—C1 | 109.51 (15) |
C2—C18—H18 | 116.7 | C18—C2—C3 | 123.48 (17) |
C19—C18—H18 | 116.7 | C18—C2—C1 | 128.36 (17) |
C19—C20—C13 | 127.60 (18) | C3—C2—C1 | 108.14 (15) |
C19—C20—H20 | 116.2 | O1—C1—C2 | 128.88 (18) |
C13—C20—H20 | 116.2 | O1—C1—C5 | 124.79 (17) |
N10—C17—H17A | 109.5 | C2—C1—C5 | 106.31 (15) |
N10—C17—H17B | 109.5 | ||
C16—N10—C10—C11 | −179.48 (19) | C5—C4—C3—O3 | −179.7 (2) |
C17—N10—C10—C11 | −2.5 (3) | C9—C4—C3—C2 | 179.4 (2) |
C16—N10—C10—C15 | 1.1 (3) | C5—C4—C3—C2 | −1.0 (2) |
C17—N10—C10—C15 | 178.13 (19) | C7—C6—C5—C4 | 0.3 (3) |
C14—C13—C12—C11 | 0.5 (3) | C7—C6—C5—C1 | −178.4 (2) |
C20—C13—C12—C11 | 179.7 (2) | C9—C4—C5—C6 | 0.4 (3) |
C13—C12—C11—C10 | 0.9 (3) | C3—C4—C5—C6 | −179.24 (18) |
N10—C10—C11—C12 | 179.1 (2) | C9—C4—C5—C1 | 179.36 (18) |
C15—C10—C11—C12 | −1.5 (3) | C3—C4—C5—C1 | −0.3 (2) |
C12—C13—C14—C15 | −1.4 (3) | C19—C18—C2—C3 | 171.6 (2) |
C20—C13—C14—C15 | 179.5 (2) | C19—C18—C2—C1 | −6.9 (4) |
C20—C19—C18—C2 | −175.0 (2) | O3—C3—C2—C18 | 1.7 (3) |
C18—C19—C20—C13 | 173.3 (2) | C4—C3—C2—C18 | −176.93 (19) |
C14—C13—C20—C19 | 2.4 (3) | O3—C3—C2—C1 | −179.5 (2) |
C12—C13—C20—C19 | −176.7 (2) | C4—C3—C2—C1 | 1.9 (2) |
C4—C9—C8—C7 | 0.1 (3) | C18—C2—C1—O1 | −4.8 (4) |
C6—C7—C8—C9 | 0.7 (3) | C3—C2—C1—O1 | 176.5 (2) |
C8—C7—C6—C5 | −0.9 (3) | C18—C2—C1—C5 | 176.7 (2) |
C8—C9—C4—C5 | −0.6 (3) | C3—C2—C1—C5 | −2.0 (2) |
C8—C9—C4—C3 | 179.0 (2) | C6—C5—C1—O1 | 1.7 (3) |
C13—C14—C15—C10 | 0.8 (3) | C4—C5—C1—O1 | −177.2 (2) |
N10—C10—C15—C14 | −179.92 (19) | C6—C5—C1—C2 | −179.7 (2) |
C11—C10—C15—C14 | 0.7 (3) | C4—C5—C1—C2 | 1.4 (2) |
C9—C4—C3—O3 | 0.7 (4) |
D—H···A | D—H | H···A | D···A | D—H···A |
C19—H19···O1 | 0.95 | 2.51 | 3.118 (3) | 122 |
C17—H17C···O3i | 0.98 | 2.50 | 3.463 (3) | 169 |
Symmetry code: (i) −x+1, y+1/2, −z+1. |
ID[1] | ID[2] | |
Acceptor–bridge | 1.31 (11) | 11.6 (2) |
Bridge–donor | 2.63 (11) | 4.9 (3) |
Deviation in acceptor | 0.0325 | 0.0159 |
Deviation in bridge | 0.0000 | 0.0473 |
Deviation in donor | 0.0035 | 0.0073 |
Solvent | ID[1] | ID[2] |
Chloroform | 483 | 539 |
Acetonitrile | 480 | 526 |
Funding information
Funding for this research was provided by: National Science Foundation (grant Nos. DMR-0934212 and DMR-1523611); Foundation for the National Institutes of Health (grant No. 1R21NS084353-01).
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