Selenosilane-Promoted Selective Mild Transformation of N-Thiophthalimides into Symmetric Disulfides

The reactivity of N-thiophthalimides with silyl chalcogenides is described. Treatment of N-thiophthalimides with bis(trimethylsilyl) sulfide [(Me3Si)2S] leads to the formation of a mixture of the corresponding disulfides and trisulfides. On the other hand, N-thiophthalimides react with bis(trimethylsilyl) selenide [(Me3Si)2Se] under TBAF catalysis to smoothly give variously substituted diaryl, divinyl, and dialkyl disulfides; formation of a selenotrisulfide (dithiaselane, RSSeSR) is rationalized as an intermediate. Exploiting the different chemical behavior of silyl chalcogenides, we have disclosed a novel, selective, and operationally simple method to access disulfides in good yields under mild conditions.

Environmentally friendly synthesis of unsymmetrical dialkyl disulfides by reacting organic halides with thiourea and sodium thiosulfate in an aqueous medium

The developed synthetic procedure is economical and environmentally friendly. It also avoids using toxic organic solvents, and an oxidant or a reductant.