corresponding gamma-(selenoethyl)allylic sulfides regioselectively in good yields. Similarly, vinylcyclopropanes undergo regioselective thiotelluration by use of a novel (PhS)(2)-(PhTe)(2) binarysystem, affording the corresponding ring-opened thiotelluration product in good yields. Furthermore, the scope and limitations of this (PhS)(2)-(PhTe)(2) binarysystem are discussed.