Anion- and auxiliary ligand-directed synthesis of cadmium(ii) complexes with 3,5-di(1H-imidazol-1-yl)benzoate

Abstract

Five new coordination polymers [Cd(L)(HPBDA)(H₂O)] (1), [Cd₂(L)₂(PBDA)(H₂O)₂]·3H₂O (2), [Cd₂(L)₂(PBDA)] (3), [Cd₃(L)₂(MBDA)₂(H₂O)₂]·2H₂O (4) and [Cd₂(L)(1,2,3-BTC)(H₂O)]·H₂O (5) were obtained by reactions of 3,5-di(1H-imidazol-1-yl)benzoic acid (HL) with varied Cd(II) salts in the presence of corresponding auxiliary ligands of 1,4-benzenedicarboxylic acid (H₂PBDA), 1,3-benzenedicarboxylic acid (H₂MBDA) and 1,2,3-benzenetricarboxylic acid (1,2,3-H₃BTC), respectively. Complex 1 with partial deprotonated HPBDA⁻ has one-dimensional (1D) chain structure, while complexes 2 and 3 are interpenetrated three-dimensional (3D) frameworks with InS and dmc topologies, respectively. Complex 4 is a (4,6)-connected 3D framework, and 5 based on tetranuclear Cd(II) secondary building units (SBUs) is a two-dimensional (2D) network. The thermal stability and photoluminescence property of the complexes were investigated.