Zn(II) Complexes with Quinoline Supported Amidate Ligands: Synthesis, Fluorescence, and Catalytic Activity

Zn(II) complexes of N-(quinolin-8-yl)picolinamide (HL1) (1) and N-2,N-6-di(quinolin-8-yl)pyridine-2,6-dicarboxamide (H2L2) (2) have been synthesized by deprotonation of the ligands and characterized by IR, NMR, and Single crystal X-ray crystallography. The mononuclear [Zn(L-1)(2)] (3) and homodinuclear [Zn-2(L-2)(2)] (4) complexes are characterized by distorted octahedral geometries stabilized by hydrogen bonding and weak pi center dot center dot center dot pi interaction. The complexes demonstrate intense fluorescence bands in comparison with their corresponding ligands with well-distinguished intensity. The complexes act as efficient catalysts in various transesterification reactions. Among those, the best results have been achieved with complex 3 in conversion of 4-nitrophenylacetate into methyl acetate within 3 h.