Oxovanadium(IV) complexes containing bidentate nitrogen-sulfur and oxygen-sulfur ligands

Abstract

A number of oxovanadium(IV) complexes containing nitrogen-sulfur and oxygen-sulfur bidentate ligands have been synthesized. The ligands employed include 2-aminoethanethiol, N-n-decyl-2-aminoethanethiol o-aminobenzenethiol, and 2-mercaptopyridine N-oxide. All the resulting oxovanadium(IV) complexes have the formula VOL 2, where L is the bidentate ligand. At tempst to prepare the N,N,-dialkyl-2-aminoethanethiol complexes of oxovanadium(IV) resulted in failure. Pyridine adducts of bis(2-mercaptopyridine N-oxide) oxovanadium(IV) (VO(PTO) 2Py) and the pyridine adduct of bis(o-aminobenethiolo)oxovanadium(IV) (VO-(ABT) 2Py) have also been prepared. The stereochemistry of these complexese has been interpreted using chemical analyses and infrared and visible spectral data and all of these complexes appear to have square pyramidal geometries except bis(2-mercaptopyridine N-oxide)oxovanadium(IV). An attempt was made to correlate the specific Lewis base acceptor and infrared spectra. It was found that the reaction of VO(ABT) 2Py with a variety of 4-substituted pyridine N-oxides (pyno) resulted in a systematic change in the visible spectra, and these changes were correlated to the Hammett σpyno values.