Transition-metal-catalyzed hydrothiolation of cyclohexylallene with benzenethiol or diphenyl disulfide

Abstract

The reaction of benzenethiol (or diphenyl disulfide) with cyclohexylallene, as a representative terminal allene, has been investigated in detail in the presence of transition metal-phosphine complexes as the catalyst. Pd(PPh3)4-catalyzed hydrothiolation of cyclohexylallene with benzenethiol in acetonitrile affords the corresponding terminal vinylic sulfide [RCH2C(SPh)=CH 2(R= c Hex)] regioselectively in good yield, whereas Pt(PPh3)4-catalyzed hydrothiolation of cyclohexylallene gives the regioisomeric vinyl sulfide successfully. Similar hydrothiolation of the allene proceeds using diphenyl disulfide, instead of benzenethiol, in the presence of triphenylphosphine and water.