Solvothermal synthesis and crystal structures of two new cadmium coordination polymers containing polynitrile ligands

Abstract

Two new coordination polymers of cadmium-containing polynitrile ligands have been synthesized using sovothermal methods. In both poly[trans,trans,trans-bis(μ-dicyanamido-κ2 N 1:N 3)bis(2-methylbenzimidazole-κN)cadmium(II)], [Cd(C2N3)2(C8H8N2)2] n , (I), and poly[trans,trans,trans-bis(2-methylbenzimidazole-κN)bis(μ-tricyanomethanido-κ2 N:N′)cadmium(II)], [Cd(C4N3)2(C8H8N2)2] n , (II), the Cd atom lies on a centre of inversion, in space groups P21/n and P21/c, respectively. In each polymer, each anionic ligand acts as a bridge between two metal centres, forming sheets of 24-membered rings, and in each structure a single N—H...N hydrogen bond links the polymer sheets to form a three-dimensional framework structure. Comparisons are made with the structures of some related complexes.