Ambidentate nucleophiles. Part 3. Reactions of phosphoroselenoates with molecular halides: the use of 1 J(PSe) as a structural diagnostic

Abstract

Sodium OO′-di-isopropyl phosphoroselenoate, Na[SeOP(OPri)2](Na[L]), reacts with molecular halides of carbon, silicon, germanium, tin, phosphorus, arsenic, and sulphur to give derivatives MLn. Comparison of the values of 1J(PSe) in the products with those in a number ofmodel compounds indicates that O-bonded isomers M[OP(OPri)2Se] are formed in LCOPh and PL3, that Se-bonded isomers M[SePO(OPri)2] are formed in LC2H5, SiMe3L, GePh3L, SnPh3L, AsL3, LSO2Ph, and L2, while SnMe3L, SnPh2L2, and SnPhL3 probably contain bidentate L. The esters P(OR)3Se (RMe or Et) are inert to reactionwith molecular halides. The compound P(OEt)3Se is a much weaker base than PPh3Se which itself is much weaker than PPh3O.