CATALYTIC OXIDATION OF TWO-ELECTRON DONORS BY DINUCLEAR COPPER(H), NICKEL(II) AND COBALT@) COMPLEXES AND EPOXIDATION OF OLEFINS USING IRON(II1) COMPLEXES

Abstract

Dinuclear copper(II) nickel(II), cobalt(l1) and iron(III) complexes derived from the Schiff base ligands obtained from the condensation of 3,3’-dimethyl-4,4’-diamino- biphenyl and pyridine-2-aldehyde and mononuclear iron(III) complexes of Schiff bases from substituted anilines and pyridine-2-aldehyde have been synthesised. Conductivity measurements on dilute solutions revealed that the dinuclear complexes are 1: 4 electrolytes while the mononuclear complexes are 1 : 2 electrolytes. The geometry of the complexes is assigned based on spectral and magnetic susceptibility values. Catalytic activity of these complexes for the oxidation of two-electron donors such as 3,5-di-t-butylcatechol (3,5- DTBC) and ascorbic acid is examined. Dinuclear iron(II1) complexes show greater activity than the mononuclear complexes for the epoxidation of olefins, namely cyclohexene and styrene using iodosyl benzene as oxygen source.