Synthesis and spectral studies on mixed ligand complexes of Cd(II) dithiocarbamates with nitrogen donors: single crystal X-ray structure of bis (4-methylpiperidinecarbodithioato-S,S′)(1,10-phenanthroline)cadmium(II)

The current article describes the synthesis and characterization of the following adducts: [Cd(2-mpipdtc)2(1,10-phen)], [Cd(2-mpipdtc)2(bipy)], [Cd(4-mpipdtc)2(1,10-phen)], [Cd(4-mpipdtc)2(bipy)] (where 2-mpipdtc− = 2-methylpiperidinecarbodithioate anion, 4-mpipdtc− = 4-methylpiperidinecarbodithioate anion, 1,10-phen = 1,10-phenanthroline and bipy = 2,2′-bipyridine). A single crystal X-ray structural analysis was carried out for [Cd(4-mpipdtc)2(1,10-phen)]. IR spectra of the complexes show the contribution of the thioureide form to the structures. Reduction in νC–N(thioureide) for the mixed ligand complexes is attributed to the change in coordination number from four to six and the steric effect exerted by 1,10-phenanthroline or 2,2′-bipyridine. Deshielding of the protons adjacent to nitrogen in the 1H NMR spectra is attributed to drift of electrons from the nitrogen of NR2, forcing electron density towards sulfur via the thioureide π-system. Single crystal X-ray structural analysis of [Cd(4-mpipdtc)2(1,10-phen)] showed that the cadmium is in a distorted octahedral environment with a CdS4N2 chromophore. The presence of 1,10-phenanthroline in the coordination sphere of Cd(dtc)2 increases the Cd–S distances and decreases the S–Cd–S angles. VBS analysis supports the determined structure.