Manganese(III) heterochelates involving quadridented Schiff bases

Abstract

Manganese(III) heterochelates of the types: (i) [Mn(Lig)( L- L)] nH 2O (where, Lig = N,N′-ethylene bis(salicylideneiminato) dianion, or N,N′-trimethylene bis(salicylideneiminato) dianion; L- L = acetylacetone or salicylaldehyde anion; n = 0 or 2) and (ii) [Mn(Lig)( L- L)] ClO 4 (where, L- L = ethylenediamine or dipyridyl) have been isolated either by the reactions of bis(acetylacetonato) manganese(II) or bis(salicyladehydato) manganese(II) with preformed Schiff bases (type-i) or by the reaction of Mn(Lig) with “ L- L” (type-ii) in absolute alcohol in the presence of oxygen under reflux. I.R. and electronic absorption spectra are reported. The first type of complex are non-conducting in DMSO, while the second are 1:1 electrolytes in ethanol. The magnetic moments of the solid complexes at room temperature range from 4·70–5·00 B.M., which show that the complexes are spin-free with no exchange or superexchange interactions. A non-planar conformation of the quadridented ligands in the manganese(III) heterochelates has been tentatively proposed.