<i>a</i><i>nsa</i>-Chromocene Complexes. 2. Isocyanide Derivatives of Cr(II) and Cr(III), Their Syntheses, X-ray Crystal Structures, and Physical Properties

Abstract

A variety of 18 e ansa -chromocene isocyanide complexes were prepared via ligand substitution on the carbonyl complexes. The relative π-accepting character of the different isocyanide ligands was evaluated from the structural, spectroscopic, and electrochemical properties of the complexes. One-electron chemical oxidation of the complexes generates low-spin, 17 e ansa -chromocene isocyanide cations, the structural and spectroscopic properties of which were compared with their neutral precursors. Density functional theory (DFT) calculations were performed on model complexes in order to elucidate the nature of the bonding between the chromium and the isocyanide ligands and to explain the effects of one-electron oxidation of the complexes.