Visible light-initiated cross-coupling between thiophenols and aryl halides (X = I and Br) to synthesize aryl thioethers over Pd/ZnIn2S4

The coupling between aryl halides and thiols to synthesize aryl thioethers via the formation of a C-S bond is an important reaction. In this manuscript, a Pd/ZnIn2S4 nanocomposite obtained via photoreduction of PdCl2(CH3CN)(2) in the presence of ZnIn2S4 was found to be an efficient bifunctional catalyst to realize the coupling reaction between thiophenols and aryl halides (X = Br and I) to yield aryl thioethers. A mechanism study reveals that the reaction involves the light-initiated generation of thiyl radicals as important intermediates. This reaction protocol can be applied to a wide range of substrate scopes, with moderate to excellent yields for the desired thioethers. This study provides a facile, green and economic strategy for the synthesis of aryl thioethers under mild conditions. This work also highlights the great potential of semiconductor-based photocatalysis in light-initiated organic syntheses.

Automated summary

In this study, a Pd/ZnIn2S4 nanocomposite was found to be an efficient bifunctional catalyst for the synthesis of aryl thioethers via the coupling reaction between thiophenols and aryl halides. The reaction mechanism involves the light-initiated generation of thiyl radicals as important intermediates. This study provides a facile, green and economic strategy for the synthesis of aryl thioethers under mild conditions, highlighting the potential of semiconductor-based photocatalysis in organic syntheses.