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Updated: Jun 1, 2026

Palladium N-Heterocyclic Carbene Complexes: Synthesis from Benzimidazolium Salts and Catalytic Activity in Carbon-carbon Bond-forming Reactions
Published on: July 30, 2017
Poly[[μ(2)-1,4-bis-(imidazol-1-ylmeth-yl)benzene]bis-(μ(4)-cyclo-hexane-1,4-dicarboxyl-ato)dicobalt(II)]
Abstract:
In the title compound, [Co(2)(C(8)H(10)O(4))(2)(C(14)H(14)N(4))](n), the two Co(II) atoms are both five-coordinated by four carboxyl-ate O atoms, derived from two different cyclo-hexane-1,4-dicarboxyl-ate (chdc) ligands, and an N atom, derived from one end of a 1,4-bis-(imidazol-1-ylmeth-yl)benzene mol-ecule (1,4-bix), in a distorted square-pyramidal environment. Each end of the chdc ligand links pairs of Co(II) atoms into a paddle-wheel assembly, i.e. Co(2)(O(2)CR')(4); these are connected into rows because of the bridging nature of the chdc ligands, and the rows are further connected into a two-dimensional layer through the 1,4-bix ligands. The 1,4-bix ligand, which is disposed about a centre of inversion, is disorderd. Two positions were discerned for the -CH(2)(C(6)H(4))CH(2)- residue, with the major component having a site-occupancy factor of 0.512 (9).
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