Syntheses and crystal structures of copper(II), zinc(II) and cadmium(II) complexes containing pyridine, quinoline and 2-methylquinoline

Nine new complexes, Cu(L1)(2)(py)(2)center dot H2O (1) [L1 = 3-(4-methoxyphenyl)acrylate, py = pyridine], Cd(L2)(2)(py)(3) (2) [L2 = 2-methyl-2-phenoxypropionate], Cd(L3)(2)(mql)(2) (3) [L3 = 3,4-(methylenedioxy)-benzoate, mql = 2-methylquinoline], Cu(py)(2)(L4)(2)center dot H2O (4) [L4 = 2-chloronicotinate], Zn(L5)(0.5)(py) (5) [L5 = butane-1,2,3,4-tetracarboxylate], [Zn(L6)(2)(ql)](2) (6) [ql = quinoline, L6 = (4-chloro-phenoxy)-acetate], [Zn(L7)(2)(H2O)(2)](mql)(2) (7) [L7 = 2-hydroxy-5-(phenyldiazenyl)benzoate], [Cd(L7)(2)(H2O)(2)](mql)(2) (8) and [Zn(ql)(2)(H2O)(4)]center dot(L8)center dot(H2O)(2) (9) [L8 = naphthalene-1,5-disulfonate], have been synthesized from an alcohol solution at room temperature and characterized by EA, IR, TGA and single-crystal X-ray diffraction. X-ray crystallographic studies show that these complexes display mononuclear, dinuclear to polymeric chain structures with an octahedral arrangement around the cadmium ions, square-pyramidal coordination geometry around the Cu ion and square-pyramidal/octahedral coordination for the Zn ions. In 1, 4 and 8, the carboxylates are monodentate ligands, while in 2 the carboxylate groups functioned as both monodentate and chelating bidentate ligands. In 3 and 7 the carboxylates are chelating bidentate ligands, the carboxylates in 5 act as a tetra-chelating bidentate ligand and the carboxylates in 6 function as a bridging bidentate ligand. The anions in 9 act as a counter ion. Rich intra- and inter-molecular weak interactions, such as classical hydrogen bonds, CH-Cl, C-H center dot center dot center dot O, CH2 center dot center dot center dot O, CH3-O, Cl-O, Cl-pi, C-H center dot center dot center dot CH3-pi and pi-pi interactions, have been analyzed. (c) 2015 Elsevier Ltd. All rights reserved.