Two pillared-layer coordination polymers based on different cadmium/carboxylate units and 2-amine-4,4′-bis(1-imidazolyl)-bibenzene

Hydrothermal reactions of CdCl2·2.5H2O with 2-amine-4,4′-bis(1-imidazolyl)-bibenzene (abimb) and 5-hydroxy-1,3-benzenedicarboxylic acid (5-HO-1,3-H2BDC) or 5-oxyacetate isophthalic acid (H3OAIP) afforded two 3D Cd(II) coordination polymers, [Cd(5-HO-1,3-BDC)(abimb)]n (1) and {[Cd3(OAIP)2(abimb)2(H2O)3]·H2O}n (2). Complexes 1 and 2 were characterized by elemental analysis, IR, powder X-ray diffraction, and single-crystal X-ray diffraction. 1 can be considered as having a 3D doubly pillared-layer framework constructed through 2D undulated (4,4) layers and abimb pillars. 2 exhibits a 3D pillared-layer framework derived from 2D (6,3) bilayers and abimb pillars. The Schläfli symbols for the two frameworks are (412 · 63) (1) and (62 · 84)2(65 · 8) (2), respectively. The thermal and photoluminescent properties of 1 and 2 were also investigated.