Cobalt(II) and iron(III) complexes with 2-substituted benzimidazole derivatives

Abstract

FeCl3 and the primary amines 2-aminobenzimidazole (abi) and 2(2′-aminophenyl)benzimidazole (apbi) give complexes for which spectroscopic and magnetic data suggest a pentacoordinate [FeCl4]. The reactions of complexes of primary amines of CoCl2 and FeCl3 with the carbonyl compounds acetylacetone (Hacac) and pyridylcarbaldehyde (pyc) yield complexes which contain the Schiff bases from the condensation of the amines and the carbonyl groups. Analytical data indicate formulae [CoCl2(abiacac)2], [CoCl2(abipyc)], [FeCl3(abiacac)], [FeCl3(abipyc)2] and [FeCl3(apbipyc)] for the complexes. The cobalt(II) complexes are pseudo-tetrahedral, while the iron complexes are tetra-, penta-, or hexa-coordinate, as deduced from spectroscopic and magnetic measurements. © 1987 Chapman and Hall Ltd.