Di­bromido­bis­(2-methyl-1H-benzimidazole-κN 3)cadmium

Bao-Cheng Liu; Yan-Ling Jin; Fa-Qian Liu

doi:10.1107/S1600536813024549

. 2013 Sep 7;69(Pt 10):m536. doi: 10.1107/S1600536813024549

Dibromidobis(2-methyl-1H-benzimidazole-κN ³)cadmium

Bao-Cheng Liu ^a,^*, Yan-Ling Jin ^a, Fa-Qian Liu ^a

PMCID: PMC3790347 PMID: 24098169

Abstract

In the title compound, [CdBr₂(C₈H₈N₂)₂], the Cd^II atom has a distorted tetrahedral coordination formed by the two imino N atoms of two 2-methylbenzimidazole ligands and two terminal bromide ligands. The Cd^II atom is slightly out of the benzimidazole planes by 0.320 (3) and 0.210 (3) Å. The dihedral angle between the benzimidazole planes is 71.6 (2)°. In the crystal, molecules are linked by N—H⋯Br hydrogen bonds into puckered layers parallel to (001).

Related literature

For background to benzimidazole, see: Roderick et al. (1972 ▶). For related crystal structures, see: Barros-García et al. (2005 ▶); Wang et al. (2010 ▶); Yang et al. (2011 ▶).

Experimental

Crystal data

[CdBr₂(C₈H₈N₂)₂]
M _r = 536.54
Monoclinic,
a = 10.007 (9) Å
b = 14.747 (12) Å
c = 12.399 (11) Å
β = 93.088 (14)°
V = 1827 (3) Å³
Z = 4
Mo Kα radiation
μ = 5.57 mm⁻¹
T = 296 K
0.22 × 0.18 × 0.16 mm

Data collection

Rigaku R-AXIS Spider diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ▶) T _min = 0.374, T _max = 0.469
9698 measured reflections
3585 independent reflections
2748 reflections with I > 2σ(I)
R _int = 0.032

Refinement

R[F ² > 2σ(F ²)] = 0.033
wR(F ²) = 0.077
S = 1.00
3585 reflections
210 parameters
H-atom parameters constrained
Δρ_max = 0.39 e Å⁻³
Δρ_min = −1.02 e Å⁻³

Data collection: RAPID-AUTO (Rigaku, 2004 ▶); cell refinement: RAPID-AUTO; data reduction: RAPID-AUTO; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL (Sheldrick, 2008 ▶); molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536813024549/kq2008sup1.cif

e-69-0m536-sup1.cif^{(25.6KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813024549/kq2008Isup2.hkl

e-69-0m536-Isup2.hkl^{(175.8KB, hkl)}

Click here for additional data file.^{(2.9KB, cdx)}

Supplementary material file. DOI: 10.1107/S1600536813024549/kq2008Isup3.cdx

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
N2—H2⋯Br1ⁱ	0.86	2.88	3.495 (4)	130
N4—H4⋯Br2ⁱⁱ	0.86	2.77	3.563 (4)	155

Open in a new tab

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

Acknowledgments

This work was supported by the NSF of Shandong Province (No. 2009ZRA02071), the Scientific Development Plan of Universities in Shandong Province (No. J09LB53) and the Doctoral Science Foundation of QUST.

supplementary crystallographic information

1. Comment

Benzimidazole and its derivatives have attracted interest because their biological activities as well as their abilities to bind different metal ions (Roderick et al., 1972). In this paper, we describe the synthesis and structure of dibromo-bis(2-methylbenzimidazole)-cadmium(II).

In the title compound, C₁₆H₁₆CdBr₂N₄, the cadmium atom has a distorted tetrahedral coordination formed by the two imino-nitrogen atoms of two 2-methyl-benzimidazole ligands and two terminal bromide ligands (Figure 1). The similar geometry was previously found in the related compounds – Cd(Cl)₂(N-(5,6-dihydro-4H- 1,3-thiazin-2-yl)-2-aminobenzimidazole)₂ (Barros-García et al., 2005), Cd(Cl)₂(2-(2-furyl)-1-(2-furylmethyl)-1H-benzimidazole)₂ (Wang et al., 2010), and Cd(I)₂(2-(2-furyl)-1-(2-furylmethyl)- 1H-enzimidazole)₂ (Yang et al., 2011). The cadmium atom is slightly out of the two benzimidazole planes by 0.320 (3) and 0.210 (3) Å, respectively. The dihedral angle between the two benzimidazole planes is 71.6 (2)°. The mean values of Cd—Br and Cd—N bond lengths are 2.562 (2) and 2.251 (3) Å, respectively. The N—Cd—Br bond angles range from 105.40 (10) to 117.76 (9)°.

In the crystal, the molecules of the title compound are linked by intermolecular N2—H2···Br1ⁱ and N4—H4···Br2ⁱⁱ hydrogen bonds (Table 1) into puckered layers parallel to (001) (Figure 2). Symmetry codes: (i) –x+1, y–1/2, –z+3/2; (ii) –x, y–1/2, –z+3/2.

2. Experimental

The ligand 2-methyl-benzimidazole (0.02 mmol) in ethanol (10 mL) was added dropwise to a ethanol (10 mL) of CdBr₂(0.01 mmol). The resulting solution was allowed to stand at room temperature. After one week colorless crystals with good quality were obtained from the filtrate and dried in air. Analysis, calculated for C₁₆H₁₆Br₂CdN₄: C 35.82, H 3.01, N 10.44%; Found: C 35.68, H 3.02, N 10.47%.