Synthesis and Characterization of a Trinuclear Zinc(II) Complex with Schiff Base (1R,2R)-(-)-Diaminocyclohexane-N,N′-biscarboxyl-salicylidene)

A homochiral complex, Zn-3(Hsalen)(2)(Py)(4)(H2O)(2) (salen = (1R,2R)-(-)-diaminocyclohexane-N,N'-biscarboxyl-salicylidene) 1, has been synthesized by Solvothermal procedure and characterized by IR, microanalysis, TGA, powder and single-crystal X-ray crystallography. It crystallizes in monoclinic space group P2 with a = 10.9439(7), b = 10.1722(6), c = 27.3450(17) angstrom, beta = 97.5060(10)degrees, V = 3018.1(3) angstrom(3), Z = 2, Zn-3(Hsalen)(2)(Py)(4)(H2O)(2), M-r = 1363.33, D-c = 1.500 g/cm(3), F(000) = 1408, mu = 1.257 mm(-1), GOOF = 1.042, the final R = 0.0601 and wR = 0.1464 for 10322 observed reflections with I > 2 sigma(I). The coordination polymer 1 possesses a 1D infinite zigzag chain architecture constructed by strong hydrogen bonding interactions and the polymeric chains are further assembled into a 2D supramolecular network structure via C-H center dot center dot center dot pi interactions between the cyclohexane and aromatic rings of the ligand of adjacent chains. Simultaneously, pi center dot center dot center dot pi stacking interactions play an important role in forming the 2D supramolecular framework.