Syntheses of Unsymmetrical Sulfides and Bis(alkylthio)methanes from Diphenylphosphinodithioate Esters

Abstract
Unsymmetrical sulfides were prepared by the reactions of diphenylphosphinodithioate esters with organolithiums in tetrahydrofuran (THF) at −78 °C or at room temperature in fairly good or excellent yields. Similarly, methylene bis(diphenylphosphinodithioate) gave bis(alkylthio)methanes by reactions with organolithiums in good yields. The use of bad-smelling thiols is avoided and the phosphorus part can be recycled after sulfurization and esterification. Allyl diphenylphosphinodithioate gave allylbenzene via SN2(C) reaction upon treatment with phenylmagnesium bromide in refluxing THF.