Dimethylaminolysis of dichlorophosphinothioyl compounds
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]But 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.