Behaviour of Some Pyridine Ligands Coordinated to Co(III) in Alkaline Solution

Abstract

[Co(NH₃)₅L](ClO₄)₃ (L = pyridine, 2-, 3-, and 4-methylpyridine) were synthesized by reaction of [(NH₃)₅Co(DMSO)(ClO₄)₃] and an appropriate ligand in DMSO solution at 80-85 ºC. The behaviour of these complexes in alkaline solution indicated that there is no evidence for the possibility of covalent hydration or pseudobase formation. However, under alkaline solution (D₂O/OD^–) deuterium exchange is the only possibility which can occur on the ortho positions of pyridine ligands coordinated to Co(III).