Decavanadate-Catalyzed Oxidative Cross-Dehydrogenative Coupling: an Efficient and Sustainable Approach toward P(O)─S Bond Formation.

A convenient green protocol has been developed for the cross-dehydrogenative coupling between thiols and P(O)-H compounds using decavanadate anion as the catalyst at room temperature under open-flask conditions. The reaction proceeds efficiently in water or ethanol without any assistance of heat, light, electricity, or unfriendly additives and tolerates a broad spectrum of functional groups, delivering the desired products in up to 95% yield. Importantly, the decavanadate catalyst can be easily recycled in gram-scale synthesis at least six times without a significant decline in reaction yield. Further, mechanistic investigations evidence the formation of tetravalent vanadium-hydroxo-species in the reaction process and reveal that the P(O)-S dehydrogenative coupling is enabled via a VV to VIV catalytic cycle.