Complexes of arylazooximes. I. structure of ligands and cobalt(III) chelates

Abstract

C-Nitrogation of aldehyde arylhydrazones gives rise to aryiazooximes. Infrared and electronic spectra favor this formulation. Aryiazooximes which undergo extensive intermolecular hydrogen bonding can apparently exist in geometrically iso-meric forms. They form very stable tris complexes with trivalent cobalt; a number of new chelate are reported. Infrared data suggest the existence of five-membered chelate rings in these complexes. The trans configuration of the tris chelates conclusively demonstrated from their proton magnetic resonance spectra. The stoically unfavorable cis imuner could not be identified. The phenylhydrazone of w-nitroacetaidehyde reacts with cobalt(II) or cobalt(III) salts in presence of excess amines to produce tris (phenylazoacetalcdoximato) cobalt (III). The tris chelates abisorb very strongly in the visible region and no evidence for crystal field bonds could be obtained.