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

The first crystal structure determination of a 1:2 co-crystalline adduct of 1,3,6,8-tetra­aza­tri­cyclo­[4.4.1.1^3,8]dodecane is presented. In the crystal, adducts are linked by C—H⋯O and C—H⋯Br hydrogen bonds, forming a two-dimensional network.

Abstract

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.

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.

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 − , −y − , 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 ▸).

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 (, ).

DHA	DH	HA	D A	DHA
O1H1N11	0.78(7)	1.97(7)	2.705(5)	158(7)
C3H3O1i	0.95	2.42	3.347(6)	164
C13H13ABr1ii	0.99	2.89	3.833(6)	159

Symmetry codes: (i) ; (ii) .

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.

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 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 C ₂ symmetry.

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.

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	C8H16N42C6H5BrO
M r	514.27
Crystal system, space group	Orthorhombic, F d d2
Temperature (K)	173
a, b, c ()	20.693(2), 21.7954(18), 9.4649(9)
V (3)	4268.8(7)
Z	8
Radiation type	Mo K
(mm1)	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 > 2(I)] reflections	5997, 1996, 1833
R int	0.062
(sin /)max (1)	0.608
Refinement
R[F 2 > 2(F 2)], wR(F 2), 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
max, min (e 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 ▸).

Supplementary Material

CCDC reference: 1057775

Additional supporting information: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Crystal data

C8H16N4·2C6H5BrO	Dx = 1.600 Mg m−3
Mr = 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

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

Refinement

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(Fo2) + (0.0386P)2] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.069	(Δ/σ)max < 0.001
S = 1.00	Δρmax = 0.24 e Å−3
1996 reflections	Δρmin = −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

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 (Ų)

	x	y	z	Uiso*/Ueq	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 (Ų)

	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)

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)

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.