Synthesis, spectral, structural, photoluminescence, thermal and DFT studies of phenylmercury(II) and Ni(II) complexes of 3-methoxycarbonyl-piperidine-1-carbodithioate

Abstract

Two new complexes [PhHg(mpc)] (1) and [Ni(mpc)2] (2) {mpc = 3-methoxycarbonyl-piperidine-1-carbodithioate} have been synthesized and characterized by elemental analyses, IR, NMR, UV–Vis and single crystal X-ray diffraction data. Both the complexes crystallize in triclinic system with space group P1¯. The geometry around the Hg(II) ion bonded with phenyl carbon and dithiosulfur atom of mpc is almost linear. Complex 2 is square planar having two unit of mpc ligand. Potassium salt of mpc and complex 1 emit violet light upon excitation at about 293 nm, while complex 2 emit blue light upon excitation at 323 nm wavelength. Cyclic voltammetry studies of free ligand (Kmpc) and its complexes 1 and 2 shows irreversible redox behaviour. Thermal behaviour of the complexes 1 and 2 have been studied which indicate that complex 1 evaporates completely over 700 °C temperature where as complex 2 converts into nickel sulfide as final residue. Frontier molecular orbital analysis reveals that complex 2 is softer and more reactive than complex 1. In the solid state, crystal structures of complexes are stabilized by intermolecular interactions. © 2018 Elsevier Ltd