One Chiral and Two Achiral 3-D Coordination Polymers Constructed by 2-Phenyl Imidazole Dicarboxylate

Two chiral three-dimensional (3-D) coordination polymers, [Cd₄(μ₃-HPhIDC)₂(μ₄-HPhIDC)₂(H₂O)] (1) and two achiral 3-D coordination polymers, [Mn_1.5(μ₃-PhIDC)(H₂O)₃] (2) and [Mn(μ₃-HPhIDC)(H₂O)]₂} (3), have been synthesized by hydro(solvo)thermal reaction, employing 2-phenyl-1H-imidazole-4,5-dicarboxylic acid (H₃PhIDC) as organic ligand, and characterized by single-crystal X-ray diffraction, elemental analyses, and IR spectra. Polymer 1 crystallizes in the orthorhombic chiral space group P2(1)2(1)2(1) and exhibits a 3-D framework, in which two-dimensional (2-D) layers are composed of right-handed helices along the b-axis and are further pillared by μ₄-HPhIDC²⁻ linkages. Polymer 2 crystallizes in trigonal chiral space group R3̅ and presents a novel 3-D structure, which is generated from 2-D honeycomb-like layers, containing similar right-handed helical chains along the a or b axes, respectively. Polymer 3 also has a 3-D architecture and is composed of novel 2-D stairlike layers in the bc plane. The theoretical prediction of the phenyl substituent effect of the H₃PhIDC ligand has first been presented.