Substituted thioureas. Part II. Trimethylthiourea and its complexes with cobalt(II) and halogens

Abstract

The n.m.r. behaviour of Co(tmtu)₂X₂(X = Br or I) complexes has been examined in acetone solutions. The effects of temperature and of excess of ligand on the isotropic shifts of the compounds have been studied. The complexes are partly dissociated and a fast ligand exchange takes place at room temperature. The position of the lines allows determination of the steric arrangement of the ligand in the complexes : only the conformer with the NH proton trans to sulphur is detectable in solution and therefore the formation of intramolecular hydrogen bonds is not possible.