Thiocyanate complexes of the group 12 metals with pyridine-2-carboxamide: Synthesis and structural characterization

Three complexes of picolinamide (pyridine-2-carboxamide, pia) and metal thiocyanates, M(SCN)2, (M = Zn, Cd, Hg), namely two polymorphs of bis(picolinamide-N,O)-bis-(thiocyanato-N)zinc(II) (1a and 1b), catena-[bis(μ-thiocyanato-S,N)-picolinamide-N,O-cadmium(II)] (2) and bis[(μ2-thiocyanato-S-thiocyanato-S-picolinamide-N,O)mercury(II)] (3) have been prepared and characterized by spectroscopic, thermal and X-ray crystallographic methods. The IR and thermal data correlate with the structures of the complexes in the solid state. The vibration bands of diagnostic value are compared to the values of the free ligands.

The three new heteroleptic thiocyanato complexes of zinc(II) (1), cadmium(II) (2) and mercury(II) (3) with picolinamide (pia) have been prepared, and their structures determined by X-ray crystallography. In all cases pia acts as a chelating ligand. Compound 1 forms two polymorphs of monomeric [Zn(SCN)2(pia)2] units. The structure of compound 2 comprises of polymeric [Cd(SCN)2(pia)]n and compound 3 of dimeric [Hg(SCN)2(pia)]2 units.Figure optionsDownload as PowerPoint slide