Novel cup-like helical coordination polymers: synthesis, crystal structures and thermal properties

摘要

By the design of ligand 1,1'-(1,5-pentamethylene)bis-1H-benzimidazole (pbbm), we have synthesized polymers {[Co(NO3)(pbbm)(2)]NO3 (.) 1/2H(2)O}(n) (1), {[CdCl(pbbm)(2)]Cl (.) CH3OH}(n) (2)and {[Cu(Ac)(2)(pbbm)]-CH3OH}(n) (3), and characterized their structures by single crystal X-ray diffraction as well as thermoanalysis. In polymers I and 2, one of the anions coordinates to the central ion, the other is located in the environment. Two pbbm ligands coordinate simultaneously to two metal centers generating one-dimensional cup-like helical chains. To our best knowledge. this cup-like structure has never been observed in the reported polymers. In polymer 3, each Cu atom is five-coordinate by two nitrogen atoms from two pbbm ligands. and three oxygen atoms from one monodentate acetate anion and one chelating acetate anion leading to one-dimensional wave-like linear chain. In addition, the DTA and TG results of the three polymers are in agreement with the crystal Structures. (C) 2003 Elsevier B.V. All rights reserved. [References: 49]