Crystal structure of catena-poly[1,3-di-benzyl-benzimidazolium [[chlorido-mercurate(II)]-di-μ-chlorido]].

The asymmetric unit of the polymeric title compound, {(C21H19N2)[HgCl3]} n , comprises one-half of the cationic mol-ecule, the other half being generated by application of twofold rotation symmetry, one Hg and two Cl atoms. The Hg(II) atom, lying on a twofold rotation axis, exhibits a distorted triangular coordination environment and is surrounded by three Cl atoms with Hg-Cl distances in the range 2.359 (2)-2.4754 (13) Å. Two additional longer distances [Hg⋯Cl = 3.104 (14) Å] lead to the formation of polymeric [HgCl1/1Cl4/2](-) chains extending along [001]. The crystal packing can be described by cationic layers alternating parallel to (-110) with the anionic chains located between the layers. The packing is consolidated by π-π stacking inter-actions between the benzene rings of the central benzimidazole entities, with centroid-to-centroid distances of 3.643 (3) Å.

Related literature

Benzimidazoles and their derivatives show anti-oxidant (Kuş et al., 2004 ▸), anti­fungal (Preston, 1974 ▸) and anthelminthic (Hazelton et al., 1995 ▸) properties and have applications in pharmacy and agriculture (Malek et al., 2006 ▸). They can also be used as ep­oxy resin curing agents, catalysts, metallic surface treatment agents (Li et al., 2003 ▸; Abboud et al., 2006 ▸) or as ionic liquids (Li et al., 2011 ▸; Chen et al., 2008 ▸). For the importance of transition metals ions in biological processes, see: Kaim & Schwederski (1994 ▸). For bond lengths of delocalized systems, see: Ennajih et al. (2009 ▸).

Experimental

Crystal data

(C21H19N2)[HgCl3]

M = 606.32

Monoclinic,

a = 20.3669 (11) Å

b = 14.8837 (7) Å

c = 7.2154 (4) Å

β = 104.372 (2)°

V = 2118.79 (19) Å3

Z = 4

Mo Kα radiation

μ = 7.65 mm−1

T = 295 K

0.19 × 0.11 × 0.05 mm

Data collection

Bruker APEXII CCD diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2011 ▸) T min = 0.646, T max = 0.746

8306 measured reflections

2401 independent reflections

1571 reflections with I > 2σ(I)

R int = 0.042

Refinement

R[F 2 > 2σ(F 2)] = 0.038

wR(F 2) = 0.085

S = 1.00

2401 reflections

124 parameters

H-atom parameters constrained

Δρmax = 2.02 e Å−3

Δρmin = −0.41 e Å−3

Data collection: APEX2 (Bruker, 2011 ▸); cell refinement: SAINT (Bruker, 2011 ▸); data reduction: SAINT; program(s) used to solve structure: SIR2002 (Burla et al., 2005 ▸); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▸); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ▸) and DIAMOND (Brandenburg & Berndt, 2001 ▸); software used to prepare material for publication: WinGX (Farrugia, 2012 ▸).

Crystal structure: contains datablock(s) I. DOI: 10.1107/S2056989015023427/wm5248sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989015023427/wm5248Isup2.hkl

Click here for additional data file.

x y z x y z . DOI: 10.1107/S2056989015023427/wm5248fig1.tif

The mol­ecular structures of the entities in the title compound. Displacement ellipsoids are drawn at the 50% probability level; H atoms are represented as small spheres of arbitrary radius. Non-labelled atoms are generated by symmetry code 2 − x, y,  − z for the cation and by symmetry code 2 − x, y,  − z for the anion.

Click here for additional data file.

1/1 4/2 − . DOI: 10.1107/S2056989015023427/wm5248fig2.tif

The polymeric anionic [HgCl1/1Cl4/2]− chain defined by long Hg—Cl distances (in dashed lines).

Click here for additional data file.

. DOI: 10.1107/S2056989015023427/wm5248fig3.tif

The crystal packing of the title compound viewed down [010] showing alternating layers of cations and anions.

Click here for additional data file.

. DOI: 10.1107/S2056989015023427/wm5248fig4.tif

The crystal packing of the title compound viewed down [001] (chain direction).

CCDC reference: 1440716

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

(C21H19N2)[HgCl3]	F(000) = 1160
Mr = 606.32	Dx = 1.901 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 2352 reflections
a = 20.3669 (11) Å	θ = 2.7–22.8°
b = 14.8837 (7) Å	µ = 7.65 mm−1
c = 7.2154 (4) Å	T = 295 K
β = 104.372 (2)°	Prism, yellow
V = 2118.79 (19) Å3	0.19 × 0.11 × 0.05 mm
Z = 4

Bruker APEXII CCD diffractometer	2401 independent reflections
Radiation source: Enraf Nonius FR590	1571 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.042
CCD rotation images, thick slices scans	θmax = 27.5°, θmin = 2.7°
Absorption correction: multi-scan (SADABS; Bruker, 2011)	h = −26→26
Tmin = 0.646, Tmax = 0.746	k = −18→13
8306 measured reflections	l = −9→9

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.085	H-atom parameters constrained
S = 1.00	w = 1/[σ2(Fo2) + (0.0419P)2] where P = (Fo2 + 2Fc2)/3
2401 reflections	(Δ/σ)max = 0.002
124 parameters	Δρmax = 2.02 e Å−3
0 restraints	Δρmin = −0.41 e Å−3

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.

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 > σ(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
Hg1	1	0.050020 (19)	0.25	0.05935 (16)
Cl2	0.91850 (7)	−0.05454 (8)	0.33958 (18)	0.0473 (3)
Cl1	1	0.20850 (14)	0.25	0.0888 (9)
N1	0.9472 (2)	0.3140 (3)	0.6672 (6)	0.0415 (10)
C4	1	0.2622 (5)	0.75	0.0484 (19)
H4	1	0.1998	0.75	0.058*
C6	0.8265 (3)	0.3186 (3)	0.6596 (8)	0.0446 (13)
C3	0.9676 (2)	0.4034 (3)	0.6988 (6)	0.0348 (11)
C1	0.9672 (3)	0.5616 (3)	0.6966 (8)	0.0463 (14)
H1	0.9458	0.6165	0.6613	0.056*
C2	0.9314 (3)	0.4838 (4)	0.6393 (7)	0.0418 (12)
H2	0.8868	0.4841	0.5667	0.05*
C5	0.8795 (3)	0.2814 (4)	0.5694 (8)	0.0524 (14)
H5A	0.8789	0.2163	0.5749	0.063*
H5B	0.8694	0.299	0.4359	0.063*
C7	0.8324 (3)	0.3053 (4)	0.8527 (9)	0.0569 (15)
H7	0.8683	0.2721	0.9258	0.068*
C11	0.7722 (3)	0.3668 (4)	0.5561 (9)	0.0574 (15)
H11	0.768	0.3764	0.4263	0.069*
C8	0.7847 (4)	0.3418 (5)	0.9352 (9)	0.0751 (19)
H8	0.7893	0.3342	1.0658	0.09*
C9	0.7303 (3)	0.3891 (5)	0.8308 (12)	0.075 (2)
H9	0.6982	0.4127	0.8894	0.091*
C10	0.7238 (3)	0.4013 (4)	0.6396 (12)	0.0695 (18)
H10	0.6869	0.4327	0.5663	0.083*

	U11	U22	U33	U12	U13	U23
Hg1	0.0830 (3)	0.02880 (19)	0.0678 (2)	0	0.02171 (18)	0
Cl2	0.0457 (8)	0.0495 (8)	0.0472 (7)	−0.0016 (6)	0.0120 (6)	0.0026 (6)
Cl1	0.146 (3)	0.0298 (12)	0.0719 (15)	0	−0.0079 (15)	0
N1	0.037 (3)	0.031 (2)	0.053 (3)	−0.0031 (19)	0.006 (2)	−0.0073 (19)
C4	0.043 (5)	0.033 (4)	0.068 (5)	0	0.010 (4)	0
C6	0.031 (3)	0.032 (3)	0.064 (4)	−0.005 (2)	−0.002 (3)	−0.008 (2)
C3	0.037 (3)	0.033 (3)	0.036 (3)	0.003 (2)	0.012 (2)	−0.003 (2)
C1	0.055 (3)	0.029 (3)	0.056 (3)	0.011 (2)	0.014 (3)	0.006 (2)
C2	0.039 (3)	0.042 (3)	0.042 (3)	0.003 (2)	0.006 (2)	−0.003 (2)
C5	0.044 (3)	0.048 (3)	0.059 (3)	−0.005 (3)	0.001 (3)	−0.018 (3)
C7	0.042 (4)	0.060 (4)	0.063 (4)	−0.004 (3)	0.001 (3)	0.003 (3)
C11	0.048 (4)	0.056 (4)	0.062 (4)	−0.007 (3)	0.001 (3)	0.002 (3)
C8	0.068 (5)	0.098 (6)	0.062 (4)	−0.013 (4)	0.020 (4)	−0.012 (4)
C9	0.052 (4)	0.075 (5)	0.106 (6)	−0.007 (4)	0.033 (4)	−0.027 (4)
C10	0.043 (4)	0.053 (4)	0.109 (6)	0.000 (3)	0.012 (4)	−0.001 (4)

Hg1—Cl1	2.359 (2)	C1—C2	1.376 (7)
Hg1—Cl2i	2.4754 (13)	C1—H1	0.93
Hg1—Cl2	2.4754 (13)	C2—H2	0.93
N1—C4	1.336 (6)	C5—H5A	0.97
N1—C3	1.397 (6)	C5—H5B	0.97
N1—C5	1.466 (6)	C7—C8	1.372 (9)
C4—N1ii	1.336 (6)	C7—H7	0.93
C4—H4	0.93	C11—C10	1.375 (9)
C6—C11	1.374 (7)	C11—H11	0.93
C6—C7	1.383 (8)	C8—C9	1.370 (10)
C6—C5	1.499 (7)	C8—H8	0.93
C3—C3ii	1.344 (9)	C9—C10	1.365 (10)
C3—C2	1.414 (7)	C9—H9	0.93
C1—C1ii	1.367 (11)	C10—H10	0.93
Cl1—Hg1—Cl2i	128.95 (3)	N1—C5—C6	111.2 (4)
Cl1—Hg1—Cl2	128.95 (3)	N1—C5—H5A	109.4
Cl2i—Hg1—Cl2	102.09 (6)	C6—C5—H5A	109.4
C4—N1—C3	107.6 (4)	N1—C5—H5B	109.4
C4—N1—C5	125.5 (4)	C6—C5—H5B	109.4
C3—N1—C5	126.8 (4)	H5A—C5—H5B	108
N1ii—C4—N1	109.7 (6)	C8—C7—C6	119.1 (6)
N1ii—C4—H4	125.2	C8—C7—H7	120.4
N1—C4—H4	125.2	C6—C7—H7	120.4
C11—C6—C7	118.7 (6)	C6—C11—C10	121.7 (6)
C11—C6—C5	121.8 (5)	C6—C11—H11	119.2
C7—C6—C5	119.5 (5)	C10—C11—H11	119.2
C3ii—C3—N1	107.5 (3)	C9—C8—C7	121.9 (6)
C3ii—C3—C2	122.2 (3)	C9—C8—H8	119
N1—C3—C2	130.2 (4)	C7—C8—H8	119
C1ii—C1—C2	122.7 (3)	C10—C9—C8	119.1 (6)
C1ii—C1—H1	118.7	C10—C9—H9	120.4
C2—C1—H1	118.7	C8—C9—H9	120.4
C1—C2—C3	115.1 (5)	C9—C10—C11	119.5 (6)
C1—C2—H2	122.5	C9—C10—H10	120.2
C3—C2—H2	122.5	C11—C10—H10	120.2
C3—N1—C4—N1ii	0.1 (2)	C11—C6—C5—N1	123.0 (5)
C5—N1—C4—N1ii	−177.2 (5)	C7—C6—C5—N1	−56.1 (7)
C4—N1—C3—C3ii	−0.2 (6)	C11—C6—C7—C8	−1.0 (8)
C5—N1—C3—C3ii	177.1 (5)	C5—C6—C7—C8	178.1 (5)
C4—N1—C3—C2	179.0 (4)	C7—C6—C11—C10	−0.5 (8)
C5—N1—C3—C2	−3.7 (8)	C5—C6—C11—C10	−179.6 (5)
C1ii—C1—C2—C3	0.0 (9)	C6—C7—C8—C9	1.7 (10)
C3ii—C3—C2—C1	−1.1 (8)	C7—C8—C9—C10	−0.8 (10)
N1—C3—C2—C1	179.8 (5)	C8—C9—C10—C11	−0.7 (10)
C4—N1—C5—C6	121.4 (5)	C6—C11—C10—C9	1.3 (9)
C3—N1—C5—C6	−55.4 (7)