Dimethylaminolysis of dichlorophosphinothioyl compounds

Abstract

The reactions of [Cl₂(S)P]₂NR (I; R = Me or Ph) with dimethylamine have been investigated. When R = Me, mono-, non-geminal bis-, and tetrakis-dimethylamino-derivatives have been isolated, and the new ring compound (II), Me₂N(S)[graphic omitted], obtained by reaction with 6 mol dimethylamine heated under reflux in chloroform solution. The analogous N-ethyl ring compound has been obtained from (I; R = Et). Attempts to synthesise the geminal bis(dimethylamino) derivatives, Cl₂(S) P·NR·P(S)(NMe₂)₂, have been unsuccessful, although the reaction of Cl₂(S)P·NHPh with dimethylamine gives (Me₂N)₂(S)P·NPh·P(S)(NMe₂)(NHPh). Aminolysis of Cl₂(O) P·NMe·P(S)Cl₂ by dimethylamine, (dimethylamino)trimethylsilane, and (diethylamino)trimethylsilane initially occurs at the phosphinothioyl centre in non-donor solvents, but in diethyl ether solution dimethylaminolysis preferentially occurs at the phosphinoyl centre. Similar results have been obtained for Cl₂(O) P·NPh·P(S) Cl₂. By contrast, dimethylaminolysis of the cyclodiphosphazane Cl(O)[graphic omitted]Bu^t occurs exclusively at the phosphonoyl centre in donor and non-donor solvents. Non-geminal bis- and tetrakis-ditnethylamino-derivatives of Cl₂(O)P·NMe·P(S)Cl₂ have also been isolated.