Epimerization of an optically active hexaco-ordinated phosphorus compound: kinetic studies

Abstract

The phenomenon of second-order asymmetric transformation often encountered for optically active spirophosphoranes has made possible the isolation of the optically pure hexaco-ordinate phosphorus compound (2). It was possible to follow the epimerization of the hexaco-ordinate phosphorus atom by n.m.r. spectroscopy and polarimetry for dimethyl sulphoxide solutions. The values of ΔG^‡(21.3 kcal mol^–1) are very close to those observed for pentaoxyspirophosphoranes.