Optically active complexes of Schiff bases. Part II. Complexes of cobalt(II) with tetradentate Schiff bases and their reactivity with oxygen

Abstract

Complexes of cobalt(II) with Schiff bases obtained by condensation of salicylaldehyde with substituted ethylenediamines have been synthesised together with five-co-ordinated pyridine adducts. E.s.r., electronic, and c.d. spectra and magnetic susceptibilities have been reported. Energy level schemes have been calculated by a ligand field approach in order to fit the magnetic properties and allow an assignment of the observed absorption bands. The reaction with oxygen has been studied and discussed in terms of both the electron configuration of the cobalt atom and the steric effects of substituents on the carbon atoms of the substituted ethylenediamines.