Synthesis, structure, luminescence and magnetic property of camphorate coordination polymers containing 5,6-dimethylbenzimidazole auxiliary ligand

Hydrothermal reactions of D-(+)-camphoric acid (D-H(2)cam) and 5,6-dimethylbenzimidazole (dmbi) with metal salts afforded three coordination polymers, namely [Cd-2(D-cam)(2)(dmbi)(4)](n) (1), [Zn-2(D-cam)(2)(dmbi)(2)](n) (2) and [(Co(D-cam)(1/2)(L-cam)(1/2)(dmbi)](n) (3), which were characterized by elemental analysis, IR, PXRD, CD, thermogravimetry and X-ray structural analysis. Complexes 1 and 2 are homochiral coordination polymers. 1 is a 1D left-handed helical chain coordination polymer constructed from tri- and tetra-dentate camphorate. 2 exhibits a 20 polymeric network assembled by tri-dentate camphorate, which belongs to 3-connected (4.8(2)) topology. 3 is a 2D achiral coordination polymer assembled by left- and right-handed 1D Co-camphorate helical chains, It is rarely observed that D-cam ligand changes to L-cam under hydrothermal condition. Three complexes are all thermally stable up to 316-425 degrees C. 1 and 2 show violet luminescence originating from ligand-centered emission. 3 exhibits an antiferromagnetic interaction in Co-2(II) dimer with J = -4.34 cm(-1). (C) 2013 Elsevier B.V. All rights reserved.