1,3-Bis(4-bromo-phen-yl)imidazolium chloride dihydrate.

In the title hydrated salt, C(15)H(11)Br(2)N(2) (+)·Cl(-)·2H(2)O, the complete imidazolium cation is generated by a crystallographic twofold axis, with one C atom lying on the axis. The chloride ion and both water mol-ecules of crystallization also lie on a crystallographic twofold axis of symmetry. The cation is non-planar, the dihedral angle formed between the central imidazolium and benzene rings being 12.9 (3)°; the dihedral angle between the symmetry-related benzene rings is 25.60 (13)°. In the crystal, O-H⋯Cl hydrogen bonds result in supra-molecular chains along c mediated by eight-membered {⋯HOH⋯Cl}(2) synthons. These are consolidated by C-H⋯O and π-π [centroid-centroid distance = 3.687 (3) Å] inter-actions.

Related literature

For the preparation of imidazolyl­idene carbenes, see: Nolan (2006 ▶); Diez-Gonzalez & Nolan (2007 ▶); Glorius (2007 ▶); Leuthaeusser et al. (2007 ▶); Alcarazo et al. (2010 ▶). For related structures, see: Luger & Ruban (1975 ▶); Cole & Junk (2004 ▶); Wan et al. (2008 ▶).

Experimental

Crystal data

C15H11Br2N2 +·Cl−·2n class="Chemical">H2O

M = 450.56

Tetragonal,

a = 17.8377 (7) Å

c = 5.1270 (1) Å

V = 1631.33 (10) Å3

Z = 4

Mo Kα radiation

μ = 5.14 mm−1

T = 120 K

0.40 × 0.03 × 0.02 mm

Data collection

Nonius KappaCCD diffractometer

Absorption correction: multi-scan (SADABS; Sheldrick, 2007 ▶) T min = 0.665, T max = 1.000

13675 measured reflections

1885 independent reflections

1654 reflections with I > 2σ(I)

R int = 0.048

Refinement

R[F 2 > 2σ(F 2)] = 0.032

wR(F 2) = 0.075

S = 1.06

1885 reflections

108 parameters

2 restraints

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.40 e Å−3

Δρmin = −0.69 e Å−3

Absolute structure: Flack (1983 ▶), 742 Friedel pairs

Flack parameter: 0.01 (2)

Data collection: COLLECT (Hooft, 1998 ▶); cell refinement: DENZO (Otwinowski & Minor, 1997 ▶) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶) and DIAMOND (Brandenburg, 2006 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810018581/hb5456sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810018581/hb5456Isup2.hkl

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

C15H11Br2N2+·Cl−·2H2O	Dx = 1.835 Mg m−3
Mr = 450.56	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P42212	Cell parameters from 2084 reflections
Hall symbol: P 4n 2n	θ = 2.9–27.5°
a = 17.8377 (7) Å	µ = 5.14 mm−1
c = 5.1270 (1) Å	T = 120 K
V = 1631.33 (10) Å3	Needle, colourless
Z = 4	0.40 × 0.03 × 0.02 mm
F(000) = 888

Nonius KappaCCD diffractometer	1885 independent reflections
Radiation source: Enraf Nonius FR591 rotating anode	1654 reflections with I > 2σ(I)
10 cm confocal mirrors	Rint = 0.048
Detector resolution: 9.091 pixels mm-1	θmax = 27.5°, θmin = 3.2°
φ and ω scans	h = −23→23
Absorption correction: multi-scan (SADABS; Sheldrick, 2007)	k = −14→23
Tmin = 0.665, Tmax = 1.000	l = −6→6
13675 measured 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)] = 0.032	H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.075	w = 1/[σ2(Fo2) + (0.0285P)2 + 2.7306P] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max = 0.001
1885 reflections	Δρmax = 0.40 e Å−3
108 parameters	Δρmin = −0.69 e Å−3
2 restraints	Absolute structure: Flack (1983), 742 Friedel pairs
Primary atom site location: structure-invariant direct methods	Flack parameter: 0.01 (2)

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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.

	x	y	z	Uiso*/Ueq
Br1	0.100493 (18)	0.463088 (18)	0.00124 (12)	0.02761 (11)
Cl1	0.13502 (7)	0.13502 (7)	0.5000	0.0552 (4)
O1	0.20493 (17)	0.20493 (17)	1.0000	0.0681 (15)
H1O	0.186 (5)	0.181 (5)	1.125 (8)	0.102*
O2	0.0584 (3)	0.0584 (3)	1.0000	0.0794 (16)
H2O	0.067 (5)	0.087 (4)	0.867 (10)	0.119*
N1	0.32639 (19)	0.38584 (18)	0.8472 (7)	0.0274 (7)
C1	0.32553 (19)	0.32553 (19)	1.0000	0.0270 (9)
H1	0.2879	0.2879	1.0000	0.032*
C2	0.3893 (3)	0.4253 (3)	0.9090 (14)	0.083 (3)
H2	0.4044	0.4714	0.8322	0.100*
C3	0.2714 (2)	0.4041 (2)	0.6525 (7)	0.0252 (8)
C4	0.2720 (2)	0.4748 (2)	0.5411 (11)	0.0382 (13)
H4	0.3075	0.5111	0.5974	0.046*
C5	0.2207 (3)	0.4925 (3)	0.3464 (9)	0.0369 (10)
H5	0.2209	0.5408	0.2685	0.044*
C6	0.1696 (2)	0.4391 (2)	0.2680 (7)	0.0267 (9)
C7	0.1683 (2)	0.3694 (2)	0.3799 (8)	0.0265 (9)
H7	0.1325	0.3334	0.3241	0.032*
C8	0.2194 (2)	0.3512 (2)	0.5749 (8)	0.0289 (10)
H8	0.2185	0.3030	0.6536	0.035*

	U11	U22	U33	U12	U13	U23
Br1	0.02725 (18)	0.0350 (2)	0.02061 (17)	0.00424 (13)	−0.0019 (3)	0.0025 (3)
Cl1	0.0652 (6)	0.0652 (6)	0.0352 (8)	−0.0031 (8)	0.0037 (10)	−0.0037 (10)
O1	0.079 (2)	0.079 (2)	0.046 (3)	−0.049 (3)	−0.009 (4)	0.009 (4)
O2	0.080 (2)	0.080 (2)	0.078 (4)	0.008 (3)	0.018 (4)	−0.018 (4)
N1	0.0252 (17)	0.0274 (18)	0.0296 (19)	0.0075 (14)	−0.0003 (15)	0.0059 (15)
C1	0.0298 (14)	0.0298 (14)	0.021 (2)	0.0017 (19)	−0.005 (3)	0.005 (3)
C2	0.056 (3)	0.061 (3)	0.132 (7)	−0.030 (3)	−0.064 (4)	0.064 (4)
C3	0.0245 (19)	0.030 (2)	0.021 (2)	0.0066 (16)	0.0005 (15)	0.0017 (16)
C4	0.038 (2)	0.033 (2)	0.044 (4)	−0.0073 (16)	−0.011 (2)	0.011 (2)
C5	0.038 (2)	0.033 (2)	0.039 (3)	−0.0040 (19)	−0.013 (2)	0.014 (2)
C6	0.0221 (19)	0.036 (2)	0.0219 (19)	0.0067 (16)	0.0002 (15)	0.0025 (16)
C7	0.0219 (19)	0.027 (2)	0.030 (2)	0.0039 (16)	0.0048 (17)	−0.0021 (17)
C8	0.026 (2)	0.029 (2)	0.032 (3)	0.0052 (16)	0.0026 (15)	0.0037 (15)

Br1—C6	1.890 (4)	C3—C8	1.383 (6)
O1—H1O	0.84 (6)	C3—C4	1.383 (6)
O2—H2O	0.87 (6)	C4—C5	1.391 (6)
N1—C1	1.331 (4)	C4—H4	0.9500
N1—C2	1.362 (6)	C5—C6	1.378 (6)
N1—C3	1.437 (5)	C5—H5	0.9500
C1—N1i	1.331 (4)	C6—C7	1.370 (6)
C1—H1	0.9500	C7—C8	1.391 (6)
C2—C2i	1.303 (10)	C7—H7	0.9500
C2—H2	0.9500	C8—H8	0.9500
C1—N1—C2	106.9 (4)	C5—C4—H4	120.1
C1—N1—C3	125.8 (4)	C6—C5—C4	119.2 (4)
C2—N1—C3	127.3 (4)	C6—C5—H5	120.4
N1—C1—N1i	109.1 (5)	C4—C5—H5	120.4
N1—C1—H1	125.4	C7—C6—C5	121.1 (4)
N1i—C1—H1	125.4	C7—C6—Br1	119.8 (3)
C2i—C2—N1	108.5 (3)	C5—C6—Br1	119.1 (3)
C2i—C2—H2	125.7	C6—C7—C8	120.2 (4)
N1—C2—H2	125.7	C6—C7—H7	119.9
C8—C3—C4	120.6 (4)	C8—C7—H7	119.9
C8—C3—N1	120.2 (4)	C3—C8—C7	119.1 (4)
C4—C3—N1	119.2 (4)	C3—C8—H8	120.5
C3—C4—C5	119.9 (4)	C7—C8—H8	120.5
C3—C4—H4	120.1
C2—N1—C1—N1i	−0.2 (4)	N1—C3—C4—C5	177.9 (4)
C3—N1—C1—N1i	178.9 (4)	C3—C4—C5—C6	0.2 (7)
C1—N1—C2—C2i	0.7 (10)	C4—C5—C6—C7	0.5 (7)
C3—N1—C2—C2i	−178.4 (6)	C4—C5—C6—Br1	−179.4 (4)
C1—N1—C3—C8	−12.5 (5)	C5—C6—C7—C8	−0.4 (6)
C2—N1—C3—C8	166.4 (5)	Br1—C6—C7—C8	179.5 (3)
C1—N1—C3—C4	168.5 (4)	C4—C3—C8—C7	1.0 (6)
C2—N1—C3—C4	−12.5 (7)	N1—C3—C8—C7	−177.9 (3)
C8—C3—C4—C5	−1.0 (7)	C6—C7—C8—C3	−0.3 (6)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1o···Cl1ii	0.84 (6)	2.28 (6)	3.1116 (19)	170 (8)
O2—H2o···Cl1	0.87 (6)	2.40 (6)	3.211 (3)	157 (7)
C1—H1···O1	0.95	2.09	3.042 (5)	180
C2—H2···O2iii	0.95	2.40	3.302 (7)	159

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1o⋯Cl1i	0.84 (6)	2.28 (6)	3.1116 (19)	170 (8)
O2—H2o⋯Cl1	0.87 (6)	2.40 (6)	3.211 (3)	157 (7)
C1—H1⋯O1	0.95	2.09	3.042 (5)	180
C2—H2⋯O2ii	0.95	2.40	3.302 (7)	159

Symmetry codes: (i) ; (ii) .