Crystal structure of the co-crystalline adduct 1,3,6,8-tetra­aza­tri­cyclo­[4.4.1.13,8]dodecane (TATD)–4-bromo­phenol (1/2)

Rivera, A.; Uribe, J.M.; Rojas, J.J.; Ríos-Motta, J.; Bolte, M.

doi:10.1107/S2056989015006684

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Volume 71| Part 5| May 2015| Pages 463-465

https://doi.org/10.1107/S2056989015006684

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Crystal structure of the co-crystalline adduct 1,3,6,8-tetraazatricyclo[4.4.1.1^3,8]dodecane (TATD)–4-bromophenol (1/2)

Augusto Rivera,^a ^* Juan Manuel Uribe,^a Jicli José Rojas,^a Jaime Ríos-Motta ^a and Michael Bolte ^b

^aUniversidad Nacional de Colombia, Sede Bogotá, Facultad de Ciencias, Departamento de Química, Cra 30 No. 45-03, Bogotá, Código Postal 111321, Colombia, and ^bInstitut für Anorganische Chemie, J. W. Goethe-Universität Frankfurt, Max-von Laue-Strasse 7, 60438 Frankfurt/Main, Germany
^*Correspondence e-mail: ariverau@unal.edu.co

Edited by J. Simpson, University of Otago, New Zealand (Received 27 March 2015; accepted 2 April 2015; online 9 April 2015)

The structure of the 1:2 co-crystalline adduct C₈H₁₆N₄·2C₆H₅BrO, (I), from the solid-state reaction of 1,3,6,8-tetraazatricyclo[4.4.1.1^3,8]dodecane (TATD) and 4-bromophenol, has been determined. The asymmetric unit of the title co-crystalline adduct comprises a half molecule of aminal cage polyamine plus a 4-bromophenol molecule. A twofold rotation axis generates the other half of the adduct. The primary inter-species association in the title compound is through two intermolecular O—H⋯N hydrogen bonds. In the crystal, the adducts are linked by weak non-conventional C—H⋯O and C—H⋯Br hydrogen bonds, giving a two-dimensional supramolecular structure parallel to the bc plane.

Keywords: crystal structure; co-crystalline adducts; TATD; proton transfer; hydrogen bonding.

CCDC reference: 1057775

1. Chemical context

The main focus of the research in our laboratory is the synthesis of a variety of molecules using cyclic aminals of the adamantane type. The prototype of these reactions is a Mannich-type reaction involving 1,3,6,8-tetraazatricyclo[4.4.1.1^3,8] dodecane (TATD) (II) with phenols which, in solution, affords di-Mannich bases of type (III) (Rivera et al., 1993 , 2005 ). These are common systems for the investigation of hydrogen bonding and proton transfer. Engaged in the development of greener synthetic pathways, we attempted a synthesis of a di-Mannich base under solvent-free conditions by simply grinding TATD and 4-bromophenol at room temperature without using any solvent in the initial step. We found that the reaction did not provide the di-Mannich base as desired. Instead, the title compound, (I), was obtained in good yield. The reaction is run in the absence of solvent, there are no by-products, and the work-up procedure is easy. Recrystallization in an appropriate solvent gave the title compound in high yield.

2. Structural commentary

Co-crystal (I) crystallized in the space group Fdd2 with one half-molecule of 1,3,6,8-tetraazatricyclo[4.4.1.1^3,8]dodecane (TATD) and one molecule of 4-bromophenol in the asymmetric unit; a twofold rotation axis generates the other half of the adduct held together by two intermolecular O—H⋯N hydrogen bonds [O⋯N 2.705 (5) Å; O—H⋯N 158 (7)°)] (Fig. 1). Unlike the situation in a related structure (Rivera et al., (2007 ), where a 1:1 adduct formed via an O—H⋯N hydrogen bond between TATD and hydroquinone, the title compound features an 1:2 adduct. Bond lengths in the TATD and 4-bromophenol molecules in (I) are within normal ranges (Allen et al., 1987 ) and are comparable to those found in similar structures (Rivera et al., 2007; Tse et al., 1977 ). The H atom of the phenolic –OH group deviates slightly from the benzene ring plane, subtending a torsion angle of 8(5)°.

Figure 1
The molecular structure of the title adduct. Displacement ellipsoids are drawn at the 50% probability level. H atoms bonded to C atoms are omitted for clarity. Hydrogen bonds are drawn as dashed lines. Atoms labelled with the suffix A are generated using the symmetry operator (−x − $[{1\over 2}]$ , −y − $[{1\over 2}]$ , z).

A significant reduction in the O⋯N distance is observed when the distance and angle in the O1—H1⋯N1 hydrogen bond [O⋯N 2.705 (5) Å; O—H⋯N 158 (7)°)] in the title compound are compared to the values found in the TATD:hydroquinone, 1:1 adduct [O⋯N 2.767 (2) Å; O—H⋯N 156.3 (10)°)] (Rivera et al., 2007). Also, the C1—O1 bond length observed here [1.355 (6) Å], is shorter than that in the hydroquinone co-crystal. This indicates an increase in hydrogen-bonding strength in the title compound, which may be due to the considerable differences in the pK_a values between the species involved in the hydrogen bond (Majerz et al., 1997 ). Compared to hydroquinone (pK_a = 9.85), p-bromophenol is more acidic (pK_a = 9.37) (Lide, 2003 ).

3. Supramolecular features

In the crystal of the title compound, the adducts are weakly linked peripherally through both non-conventional C—H⋯O and C—H⋯Br hydrogen bonds (Table 1) giving a two dimensional supramolecular structure parallel to the bc plane. (Fig. 2). This is similar to the structure of the 4-bromophenol adduct with urotropine (Tse et al., 1977).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N11	0.78 (7)	1.97 (7)	2.705 (5)	158 (7)
C3—H3⋯O1ⁱ	0.95	2.42	3.347 (6)	164
C13—H13A⋯Br1ⁱⁱ	0.99	2.89	3.833 (6)	159
Symmetry codes: (i) $[-x-{\script{1\over 2}}, -y-1, z+{\script{1\over 2}}]$ ; (ii) x, y, z-1.

Figure 2
The crystal packing of the title compound, showing two of the chains that extend along the crystal c-axis direction. C—H⋯O and C—H⋯Br hydrogen bonds are drawn as dashed lines.

4. Database survey

A database search (CSD version 5.36, November 2014 plus two updates) for 4-bromophenol yielded 17 hits with 21 fragments. The mean C—O bond length in these structures is 1.35 (5) Å and the mean C—Br bond length is 1.91 (3) Å. These values are in excellent agreement with those of the title compound, i.e. O1—C1 1.355 (6) and Br1—C4 1.907 (5) Å.

A database search for 1,3,6,8-tetraazatricyclo[4.4.1.1^3,8]dodecane yielded only three hits, two determinations of the compound itself (Murray-Rust, 1974 ; Rivera et al., 2014 ) and a co-crystal of the aminal with hydroquinone (Rivera et al., 2007). While the molecules of 1,3,6,8-tetraazatricyclo[4.4.1.1^3,8]dodecane itself have $[\overline{4}]$ 2m symmetry, the molecules in the co-crystal of TATD with hydroquinone have mirror symmetry. In the title compound, on the other hand, the 1,3,6,8-tetraazatricyclo[4.4.1.1^3,8]dodecane molecule displays C₂ symmetry.

5. Synthesis and crystallization

1,3,6,8-tetraazatricyclo[4.4.1.1^3,8]dodecane (TATD) (0.21g, 1.25 mmol) and 4-bromophenol (0.43g, 2.5 mmol) were manually mixed in a mortar with pestle at room temperature for 20 min as required to complete the reaction (TLC). The mixture was then dissolved in a minimum amount of methanol and left to crystallize at room temperature. Subsequent recrystallization with MeOH then yielded the title compound as white crystals in 78% yield, m.p. = 367–368 K.

6. Refinement details

Crystal data, data collection and structure refinement details are summarized in Table 2. All the H atoms were located in a difference electron density map. The hydroxyl H atom was refined freely, while C-bound H atoms were fixed geometrically (C—H = 0.95 or 0.99 Å) and refined using a riding-model approximation, with U_iso(H) set to 1.2U_eq of the parent atom.

Table 2
Experimental details

Crystal data
Chemical formula	C₈H₁₆N₄·2C₆H₅BrO
M_r	514.27
Crystal system, space group	Orthorhombic, Fdd2
Temperature (K)	173
a, b, c (Å)	20.693 (2), 21.7954 (18), 9.4649 (9)
V (Å³)	4268.8 (7)
Z	8
Radiation type	Mo Kα
μ (mm⁻¹)	3.82
Crystal size (mm)	0.29 × 0.27 × 0.23

Data collection
Diffractometer	Stoe IPDS II two-circle
Absorption correction	Multi-scan (MULABS; Spek, 2009 ; Blessing, 1995 )
T_min, T_max	0.847, 0.972
No. of measured, independent and observed [I > 2σ(I)] reflections	5997, 1996, 1833
R_int	0.062
(sin θ/λ)_max (Å⁻¹)	0.608

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.069, 1.01
No. of reflections	1996
No. of parameters	132
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.24, −0.41
Absolute structure	Flack x determined using 792 quotients [(I⁺)−(I⁻)]/[(I⁺)+(I⁻)] (Parsons et al., 2013 )
Absolute structure parameter	0.003 (16)
Computer programs: X-AREA (Stoe & Cie, 2001 ), SHELXS97 and XP in SHELXTL-Plus (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ) and Mercury (Macrae et al., 2006 ).

Supporting information

CCDC reference: 1057775

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989015006684/sj5449sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015006684/sj5449Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S2056989015006684/sj5449Isup3.cml

checkCIF report

Computing details top

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA (Stoe & Cie, 2001); data reduction: X-AREA (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015).

1,3,6,8-Tetraazatricyclo[4.4.1.1^3,8]dodecane–4-bromophenol (2/1) top

Crystal data top

C₈H₁₆N₄·2C₆H₅BrO	D_x = 1.600 Mg m⁻³
M_r = 514.27	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Fdd2	Cell parameters from 7202 reflections
a = 20.693 (2) Å	θ = 3.7–26.0°
b = 21.7954 (18) Å	µ = 3.82 mm⁻¹
c = 9.4649 (9) Å	T = 173 K
V = 4268.8 (7) Å³	Block, colourless
Z = 8	0.29 × 0.27 × 0.23 mm
F(000) = 2080

Data collection top

Stoe IPDS II two-circle diffractometer	1833 reflections with I > 2σ(I)
Radiation source: Genix 3D IµS microfocus X-ray source	R_int = 0.062
ω scans	θ_max = 25.6°, θ_min = 3.7°
Absorption correction: multi-scan (MULABS; Spek, 2009; Blessing, 1995)	h = −22→24
T_min = 0.847, T_max = 0.972	k = −25→26
5997 measured reflections	l = −11→11
1996 independent reflections

Refinement top

Refinement on F²	Hydrogen site location: mixed
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F² > 2σ(F²)] = 0.032	w = 1/[σ²(F_o²) + (0.0386P)²] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.069	(Δ/σ)_max < 0.001
S = 1.01	Δρ_max = 0.24 e Å⁻³
1996 reflections	Δρ_min = −0.41 e Å⁻³
132 parameters	Absolute structure: Flack x determined using 792 quotients [(I⁺)-(I^-)]/[(I⁺)+(I^-)] (Parsons et al., 2013)
1 restraint	Absolute structure parameter: 0.003 (16)

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.

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Br1	−0.11272 (3)	−0.43922 (2)	1.02771 (5)	0.03734 (18)
O1	−0.2465 (2)	−0.40437 (17)	0.4684 (4)	0.0311 (9)
H1	−0.233 (4)	−0.375 (3)	0.432 (7)	0.036 (18)*
C1	−0.2172 (3)	−0.4091 (2)	0.5959 (5)	0.0232 (11)
C2	−0.2281 (3)	−0.4622 (2)	0.6734 (6)	0.0288 (12)
H2	−0.2567	−0.4926	0.6379	0.035*
C3	−0.1978 (3)	−0.4710 (2)	0.8016 (5)	0.0281 (11)
H3	−0.2048	−0.5077	0.8536	0.034*
C4	−0.1570 (3)	−0.4262 (2)	0.8536 (5)	0.0246 (10)
C5	−0.1468 (2)	−0.37234 (18)	0.7795 (7)	0.0252 (10)
H5	−0.1190	−0.3416	0.8165	0.030*
C6	−0.1773 (3)	−0.3635 (2)	0.6514 (5)	0.0257 (11)
H6	−0.1711	−0.3263	0.6009	0.031*
N11	−0.2299 (2)	−0.30437 (16)	0.3032 (4)	0.0241 (9)
N12	−0.2997 (2)	−0.2824 (2)	0.0903 (4)	0.0276 (10)
C11	−0.2500	−0.2500	0.3809 (7)	0.0278 (16)
H11A	−0.2137	−0.2379	0.4431	0.033*	0.5
H11B	−0.2863	−0.2621	0.4431	0.033*	0.5
C12	−0.2756 (3)	−0.3255 (2)	0.1929 (6)	0.0354 (14)
H12A	−0.2542	−0.3592	0.1404	0.042*
H12B	−0.3134	−0.3436	0.2416	0.042*
C13	−0.1623 (3)	−0.3018 (2)	0.2559 (7)	0.0398 (14)
H13A	−0.1497	−0.3431	0.2227	0.048*
H13B	−0.1349	−0.2919	0.3386	0.048*
C14	−0.1470 (3)	−0.2560 (3)	0.1394 (6)	0.0389 (13)
H14A	−0.1120	−0.2287	0.1734	0.047*
H14B	−0.1298	−0.2790	0.0574	0.047*
C15	−0.2500	−0.2500	0.0114 (7)	0.0314 (16)
H15A	−0.2282	−0.2801	−0.0507	0.038*	0.5
H15B	−0.2718	−0.2199	−0.0507	0.038*	0.5

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0464 (3)	0.0333 (2)	0.0323 (2)	0.0043 (3)	−0.0102 (3)	0.0045 (2)
O1	0.039 (3)	0.0219 (18)	0.0323 (19)	−0.0044 (18)	−0.0097 (17)	0.0049 (15)
C1	0.021 (3)	0.022 (2)	0.027 (2)	0.004 (2)	0.001 (2)	−0.0017 (19)
C2	0.032 (3)	0.020 (2)	0.034 (3)	−0.003 (2)	0.003 (2)	0.001 (2)
C3	0.034 (3)	0.020 (2)	0.030 (3)	−0.001 (2)	0.005 (2)	0.005 (2)
C4	0.029 (3)	0.024 (2)	0.021 (2)	0.004 (2)	0.004 (2)	0.0013 (18)
C5	0.026 (3)	0.0200 (18)	0.030 (2)	−0.0030 (18)	0.001 (3)	−0.002 (3)
C6	0.033 (3)	0.018 (2)	0.027 (2)	−0.003 (2)	0.002 (2)	0.0007 (18)
N11	0.032 (2)	0.0210 (18)	0.019 (2)	−0.0012 (17)	0.0013 (17)	−0.0048 (15)
N12	0.025 (2)	0.036 (2)	0.0222 (19)	−0.009 (2)	−0.0016 (18)	−0.0016 (17)
C11	0.043 (5)	0.024 (3)	0.016 (3)	0.005 (3)	0.000	0.000
C12	0.050 (4)	0.027 (3)	0.029 (3)	−0.014 (3)	−0.006 (2)	−0.001 (2)
C13	0.034 (3)	0.041 (3)	0.045 (4)	0.006 (2)	0.002 (3)	0.004 (3)
C14	0.027 (3)	0.061 (4)	0.029 (3)	−0.006 (3)	0.003 (2)	0.001 (3)
C15	0.034 (4)	0.046 (4)	0.015 (3)	−0.006 (3)	0.000	0.000

Geometric parameters (Å, º) top

Br1—C4	1.907 (5)	N12—C15	1.453 (6)
O1—C1	1.355 (6)	N12—C14ⁱ	1.462 (8)
O1—H1	0.78 (7)	C11—N11ⁱ	1.456 (5)
C1—C2	1.388 (7)	C11—H11A	0.9900
C1—C6	1.393 (7)	C11—H11B	0.9900
C2—C3	1.380 (8)	C12—H12A	0.9900
C2—H2	0.9500	C12—H12B	0.9900
C3—C4	1.381 (7)	C13—C14	1.520 (8)
C3—H3	0.9500	C13—H13A	0.9900
C4—C5	1.384 (7)	C13—H13B	0.9900
C5—C6	1.380 (8)	C14—N12ⁱ	1.462 (8)
C5—H5	0.9500	C14—H14A	0.9900
C6—H6	0.9500	C14—H14B	0.9900
N11—C11	1.456 (5)	C15—N12ⁱ	1.453 (6)
N11—C13	1.470 (8)	C15—H15A	0.9900
N11—C12	1.482 (7)	C15—H15B	0.9900
N12—C12	1.441 (7)

C1—O1—H1	107 (5)	N11—C11—H11B	107.5
O1—C1—C2	117.4 (5)	N11ⁱ—C11—H11B	107.5
O1—C1—C6	123.1 (5)	H11A—C11—H11B	107.0
C2—C1—C6	119.5 (5)	N12—C12—N11	119.5 (4)
C3—C2—C1	120.4 (5)	N12—C12—H12A	107.4
C3—C2—H2	119.8	N11—C12—H12A	107.4
C1—C2—H2	119.8	N12—C12—H12B	107.4
C2—C3—C4	119.6 (4)	N11—C12—H12B	107.4
C2—C3—H3	120.2	H12A—C12—H12B	107.0
C4—C3—H3	120.2	N11—C13—C14	116.4 (5)
C3—C4—C5	120.8 (5)	N11—C13—H13A	108.2
C3—C4—Br1	119.8 (4)	C14—C13—H13A	108.2
C5—C4—Br1	119.4 (4)	N11—C13—H13B	108.2
C6—C5—C4	119.6 (4)	C14—C13—H13B	108.2
C6—C5—H5	120.2	H13A—C13—H13B	107.3
C4—C5—H5	120.2	N12ⁱ—C14—C13	116.6 (5)
C5—C6—C1	120.1 (4)	N12ⁱ—C14—H14A	108.1
C5—C6—H6	119.9	C13—C14—H14A	108.1
C1—C6—H6	119.9	N12ⁱ—C14—H14B	108.1
C11—N11—C13	113.2 (3)	C13—C14—H14B	108.1
C11—N11—C12	115.3 (4)	H14A—C14—H14B	107.3
C13—N11—C12	113.9 (4)	N12ⁱ—C15—N12	118.2 (6)
C12—N12—C15	114.7 (4)	N12ⁱ—C15—H15A	107.8
C12—N12—C14ⁱ	114.9 (4)	N12—C15—H15A	107.8
C15—N12—C14ⁱ	114.8 (4)	N12ⁱ—C15—H15B	107.8
N11—C11—N11ⁱ	119.3 (5)	N12—C15—H15B	107.8
N11—C11—H11A	107.5	H15A—C15—H15B	107.1
N11ⁱ—C11—H11A	107.5

O1—C1—C2—C3	177.5 (5)	C12—N11—C11—N11ⁱ	−51.2 (3)
C6—C1—C2—C3	−2.7 (8)	C15—N12—C12—N11	55.6 (7)
C1—C2—C3—C4	1.0 (8)	C14ⁱ—N12—C12—N11	−80.7 (7)
C2—C3—C4—C5	0.7 (8)	C11—N11—C12—N12	50.6 (7)
C2—C3—C4—Br1	−178.0 (4)	C13—N11—C12—N12	−82.8 (6)
C3—C4—C5—C6	−0.6 (8)	C11—N11—C13—C14	−69.9 (6)
Br1—C4—C5—C6	178.1 (4)	C12—N11—C13—C14	64.4 (6)
C4—C5—C6—C1	−1.2 (8)	N11—C13—C14—N12ⁱ	2.4 (7)
O1—C1—C6—C5	−177.4 (5)	C12—N12—C15—N12ⁱ	−53.9 (3)
C2—C1—C6—C5	2.8 (8)	C14ⁱ—N12—C15—N12ⁱ	82.4 (4)
C13—N11—C11—N11ⁱ	82.4 (4)

Symmetry code: (i) −x−1/2, −y−1/2, z.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N11	0.78 (7)	1.97 (7)	2.705 (5)	158 (7)
C3—H3···O1ⁱⁱ	0.95	2.42	3.347 (6)	164
C13—H13A···Br1ⁱⁱⁱ	0.99	2.89	3.833 (6)	159

Symmetry codes: (ii) −x−1/2, −y−1, z+1/2; (iii) x, y, z−1.

Acknowledgements

We acknowledge the financial support provided to us by the Dirección de Investigaciones, Sede Bogotá (DIB) at the Universidad Nacional de Colombia. JMU and JJR thank COLCIENCIAS for a fellowship.

References

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