1-Cyano­methyl-4-aza-1-azonia­bicyclo­[2.2.2]octane bromide dihydrate

Ying Cai

doi:10.1107/S1600536810019926

. 2010 Jun 5;66(Pt 7):o1527. doi: 10.1107/S1600536810019926

1-Cyanomethyl-4-aza-1-azoniabicyclo[2.2.2]octane bromide dihydrate

Ying Cai ^a,^*

PMCID: PMC3006882 PMID: 21587777

Abstract

In the crystal structure of the title compound, C₈H₁₄N₃ ⁺·Br⁻·2H₂O, intermolecular O—H⋯O and O—H⋯Br hydrogen bonding occurs. The water molecules are connected into chains extending in the a-axis direction. The bromide anions are connected to the water molecules, forming 10-membered rings. The cations are connected to the anions via weak C—H⋯Br interactions. Two carbon atoms of the cation are disordered and were refined using a split model (occupancy ratio 0.70:0.3).

Related literature

For uses of DABCO (1,4-biazabicyclo[2.2.2]octane) and its derivatives, see: Basaviah et al. (2003 ▶); Chen et al. (2010 ▶).

Experimental

Crystal data

C₈H₁₄N₃ ⁺·Br⁻·2H₂O
M _r = 268.16
Orthorhombic,
a = 7.461 (5) Å
b = 12.008 (7) Å
c = 13.236 (8) Å
V = 1185.8 (13) Å³
Z = 4
Mo Kα radiation
μ = 3.45 mm⁻¹
T = 293 K
0.20 × 0.20 × 0.20 mm

Data collection

Rigaku Mercury CCD diffractometer
Absorption correction: multi-scan (CrystalClear; Rigaku, 2005 ▶) T _min = 0.701, T _max = 1.000
13047 measured reflections
2711 independent reflections
2219 reflections with I > 2σ(I)
R _int = 0.073

Refinement

R[F ² > 2σ(F ²)] = 0.041
wR(F ²) = 0.077
S = 1.01
2711 reflections
140 parameters
101 restraints
H-atom parameters constrained
Δρ_max = 0.29 e Å⁻³
Δρ_min = −0.29 e Å⁻³
Absolute structure: Flack (1983 ▶), 1134 Friedel pairs
Flack parameter: 0.033 (14)

Data collection: CrystalClear (Rigaku, 2005 ▶); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810019926/nc2186sup1.cif

e-66-o1527-sup1.cif^{(17.8KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810019926/nc2186Isup2.hkl

e-66-o1527-Isup2.hkl^{(133.2KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1O1⋯Br1	0.82	2.58	3.354 (3)	159
O2—H1O2⋯O1	0.82	1.98	2.791 (4)	170
O1—H2O1⋯O2ⁱ	0.82	1.99	2.788 (5)	164
O2—H2O2⋯Br1ⁱ	0.82	2.50	3.314 (3)	172
C7—H7A⋯Br1	0.97	2.81	3.740 (5)	161
C7—H7B⋯Br1ⁱⁱ	0.97	2.92	3.792 (8)	151

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Symmetry codes: (i) Inline graphic ; (ii) .

supplementary crystallographic information

Comment

1,4-Diazabicyclo[2.2.2]octane (DABCO) is used as a organocatalyst for a large number of reactions because of its nucleophilicity (Basaviah et al., 2003) and some of its derivatives are ferroelectrics (Chen et al., 2010). The structure determination of the title compound was performed within a project on the electric properties of 1,4-Diazabicyclo[2.2.2]octane derivatives. Within this project the crystals of the title compound were obtained by accident.

In the crystal stucture of the title compound two C atoms of the cation are disordered (Fig. 1). The cations and anions are connected by weak intermolecular C—H···Br interactions. The bromide anions are additionally linked to the water molecules via intermolecular O—H···Br hydrogen bonding and the water molecules are connected into chains that elongate in the direction of the a axis (Fig. 2). Each water molecule act as hydrogen bond donor and acceptor. The bromide anions and the water molecules forming ten-membered rings.

Experimental

1,4-Diaza-bicyclo[2.2.2]octane (dabco) (0.05?mol, 5.6?g) and bromoacetonitrile (0.1?mol, 12.00?g) were dissolved in CH₃CN(40?ml). The mixture was stirred for 1?h leading to a white precipitate of the title compound whish was filtered off, washed with acetonitrile and dried. Yield: 80%. Afterwards a mixture of 1-(cyanomethyl)-4-aza-1-azonia-bicyclo[2.2.2]octane bromide (0.01?mol 2.32?g) and tetrafluoro-borate sodium (0.01?mol 1.10?g) in H₂O (20?ml) was stirred until a clear solution was obtained. On slow evaporation of the solvent colourless plate crystals of the title compand suitable for X-ray analysis were obtained accidently.

The dielectric constant of the title compound as a function of temperature goes smoothly between 93 and 363?K and there is no dielectric anomaly observed within the measured temperature range.