Thiophosphinyl halides

Metal dithiophosphinato complexes are usually prepared by metathesis of metal halides with alkali metal or ammonium dithiophoshinates, but can also be conveniently prepared by reactions of /i .v(thiophosphinyl)disul fanes, R2(S)PSSP(S)R2, with metal species.87 The electrochemical oxidation of metals in acetonitrile solution, in the presence of diphenylphosphine and sulfur affords M(S2PPh2)2 (M = Co, Zn, Cd),88 but this is not a preparative method. 

A patent indicates that thiophosphinyl halides behave as expected with Grignard reagents tertiary phosphine sulfides are formed (77). 

Symmetrical diphosphine disulphides are thermally quite stable and oxidation with nitric add or hydrogen peroxide gives phosphonic adds. With halogens, either thiophosphinyl halides, R2PSCI or halogeno phosphoranes, R2PCI3 can be obtained. Diphosphine disulphides are very reactive and if heated with 10% NaOH solution, they are split into a sodium phosphinothionate and a secondary phosphine sulphide. 

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