Sulfur transfer reaction from phosphine sulfides to phosphines assisted by metal ions

The sulfur transfer reaction from phosphine sulfides to various phosphines in the presence of metal ion was studied; in the presence of Cu(I), a sulfur transfer reaction from dppmS2 (bis(diphenylphosphino)methane disulfide) to dppm (bis(diphenylphosphino)methane) or to dppa (bis(diphenylphosphino)amine) occurs and the product [Cu(dppmS)2]+ (1) and [Cu(dppmS)(dppaS)]+ (2) was obtained quantitatively. In the presence of Zn(II), sulfur transfer to various phosphines can be carried out catalytically. The reaction mechanism has been proposed from the difference in the reactivity of diphosphines and metal ions.