Syntheses, crystal structures and electrochemical properties of Zn(II), Ag(I) and Cu(II) complexes based on 2-[(4,6-dimethylpyrimidinyl)-2-thio] acetic acid

Abstract

Three inorganic–organic supramolecular networks based on 2-[(4,6-dimethylpyrimidinyl)-2-thio] acetic acid (HL) and Zn(II), Ag(I) and Cu(II) salts have been prepared and structurally characterized by single-crystal X-ray diffractions. Mononuclear complex [ZnL 2(1,2-DAP)]·2H 2O ( 1) (1,2-DAP = 1,2-diaminopropane) exhibits a three-dimensional cavity architecture through hydrogen bonds and π–π interaction. The crystal structure of (AgL) n ( 2) consists of two-dimensional brick-wall framework. [Cu 2L 4(CH 3OH) 2]·3CH 3OH ( 3) contains dinuclear copper units, which are bridged by four acetate groups. Electrochemical behaviors have been systematically investigated by different electrochemical methods. Complex 3 shows a pair of quasi-reversible redox peaks. The electrode process is controlled by diffusion. The diffusion coefficient ( D) for 3 is about 10 −6 cm 2 s −1. The electron transfer number ( n) and the transfer coefficient ( α) are 2 and 0.33, respectively.