Hydrothermal syntheses and crystal structures of five complexes with 3,5-dinitrosalicylate and N-donor ligand: Helical chains, 2D network and extended 3D structures

Five complexes with 3,5-dinitrosalicylate (3,5-(NO2)(2)sal) and N-donor ligand, [Cd{3,5-(NO2)(2)sal}(phen)(H2O)](n) (1), Ni(3,5-(NO2)(2)sal)(phen)(H2O)(2) (2), [Co(3,5-(NO2)(2)sal}(4,4'-bipy)(H2O)center dot(H2O)](n) (3), [Co(3,5-(NO2)(2)sal}(phen)](n) (4) and [Zn(3,5-(NO2)(2)sal} (phen)](n) (5), have been synthesized by hydrothermal reactions and characterized by single crystal X-ray analysis, where phen = 1,10-phenanthroline and 4,4'-bipy = 4,4'-bipyridine. There are one-dimensional left- and right-handed helical chains in complexes 1, 4 and 5, an extended 3D structure in 2, and a 2D rectangular grid-like network in 3. The C - H center dot center dot center dot O hydrogen bonds lead to the formation of 3D supramolecular structures in the five title complexes. The fluorescent spectra study show that compounds 1 and 5 exhibit weak fluorescent emission in the solid state at room temperature. (c) 2007 Elsevier B.V. All rights reserved.