SYNTHESIS AND PROPERTIES OF NEW DIBENZOTETRAAZA[14] ANNULENES AND ITS METAL CHELATES

Abstract

Abstract New tetraaza-macrocylic ligands, 6,13-diaryl-1,8-dihydrodibenzo[b,i] [1,4,8,11] tetraazacyclotetradecenes, and its copper(II), nickel(II), cobalt(II) and iron(III) complexes were prepared and characterized. The diimidazole complexes of iron(III) with these N4-macrocyclic ligands are of low-spin type. ESR and Mossbauer spectral studies led to the conclusion that one unpaired electron lies in the dxy orbital of iron atom for the iron(III) complexes.