Synthesis, characterization and X-ray crystal structures of two polymorphs of a cobalt(III) complex with a N3O2 pentadentate Schiff base ligand, and benzylamine: spectral and electrochemical studies

Abstract

The title complex [CoIII{(naph)2dpt}(bzlan)]BPh4, where (naph)2dpt stands for bis-(2-hydroxy-1-naphthaldimine)-N-dipropylenetriamine dianion and bzlan for benzylamine, has been synthesized and characterized by elemental analyses, IR, UV–Vis and 1H NMR spectroscopy. The structures of two possibly concomitant polymorphs, obtained from methanolic solution, [polymorph I (monoclinic, centrosymmetric, red-brown, thickish prismatic platelets) and polymorph II (orthorhombic, noncentrosymmetric, ochre olive-green, thin laths)] have been determined by X-ray crystallography. The geometry around the central cobalt ion is distorted octahedral in both polymorphs, but the benzylamine shows different kinds of orientation and disorder.