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Published on: August 12, 2019
A dinuclear complex of cobalt(II) with 2,2'-(1,4-butanediyl)dibenzimidazole
Jin Yang1, Jian Fang Ma, Ying Ying Liu
1Department of Chemistry, Northeast Normal University, Changchun 130024, People's Republic of China.
Abstract:
The title complex, [mu-2,2'-(1,4-butanediyl)di-1H-benzimidazole-kappa2N3:N3']bis{[2,2'-(1,4-butanediyl)di-1H-benzimidazole-kappa2N3,N3'](nitrato-kappaO)cobalt(II)} dinitrate ethanol disolvate, [Co2(NO3)2(C18H18N4)3](NO3)2.2C2H6O, was obtained from self-assembly of cobalt(II) nitrate with 2,2'-(1,4-butanediyl)dibenzimidazole (L). The complex molecule lies about an inversion centre and the flexible L ligands act in both bridging and chelating modes to form a dinuclear complex with unanticipated nine-membered chelate rings. The unique uncoordinated nitrate anion is linked to the cation by pairs of N-H...O hydrogen bonds, which determine the overall cation conformation. Cation-anion sets are then linked by a further N-H...O hydrogen bond to generate a chain along [010]. Chains are linked by C-H...O hydrogen bonds to form sheets in the (100) plane.
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