Chiral configurations in cyclophosphazene chemistry

Abstract

The pentavalent phosphorus atoms in cyclophosphazenes (NPXY)(n) are tetra-coordinated and their potential centers of chirality are analogous to those for tetrahedral carbon derivatives. Although the possibility of optical isomerism in cyclophosphazene derivatives was first discussed over 50 years ago, the stereogenic properties of substituted cyclophosphazene compounds have only been investigated systematically for about 15 years. This review summarizes the recent work reported on the stereogenic properties of cyclophosphazenes. The review will also cover those previously published compounds where the centers of chirality were not explicitly recognized, in order that the stereogenic properties of new compounds will be taken into account in future studies. (C) 2015 Elsevier B.V. All rights reserved.