Direct electrochemical synthesis of pyridine-2-thionato complexes of nickel(II): the crystal structure of (2,2′-bipyridine)bis(pyridine-2-thionato)nickel(II)-2,2′-bipyridine(2/1)

Abstract

The compound [Ni(pyt)₂] has been prepared in good yield by electrochemical oxidation of the metal in a solution of pyridine-2-thione (Hpyt) in acetonitrile. When pyridine (py), 2,2′-bipyridine (bipy), or 1,10-phenanthroline (phen) is present in the electrochemical cell the corresponding adducts [Ni(pyt)₂(py)₂], [Ni(pyt)₂(bipy)], or [Ni(pyt)₂(phen)] is obtained. The crystal structure of [Ni(pyt)₂(bipy)]·0.5 bipy is monoclinic, with a= 10.409(2), b= 12.013(3), c= 19.790(3)Å, β= 103.95(3)°, space group P2₁/c, and R= 0.032 for 3 176 reflections with |I_o| > 3σ|I_o|. The molecule has a distorted octahedral NiN₄S₂ kernel, with average bond distances of 2.065 Å for Ni–N and 2.485 Å for Ni–S. The vibrational and electronic spectra of the compounds are discussed.