The electron spin resonance spectra and structure of chlorophosphoranyl radicals in solution

Abstract

Chlorophosphoranyl radicals of the types Bu^tO(R)_nṖCl_3–n and Bu^tO(RO)_nṖCl_3–n have been prepared by addition of photochemically generated t-butoxyl radicals to chlorophosphines in fluid solution. The e.s.r. spectra of these radicals are characterised by very large phosphorus-31 hyperfine splittings (ca. 1000 G) and readily resolvable ³⁵Cl and ³⁷Cl splittings (ca. 40 G). The chlorine atoms are probably held rigidly (on the e.s.r. time scale) at apical sites in these chlorophosphoranyl radicals, the apicophilicity of chlorine being greater than that of an alkoxy-group. The reactions of chlorophosphoranyl radicals are discussed.