Single-Step Generation of β-Ketosulfides from Epoxides and Thiols Catalyzed by a Ru(II)–Pincer Complex

β-Ketosulfides are synthetic precursors for a variety of organic compounds, and can also be found among natural products and medicinally active materials. Many procedures for the synthesis of β-ketosulfides are currently available, but they are typically inherently atom-inefficient, requiring the use of preinstalled leaving groups or additives, and leading to the generation of chemical waste. Herein, we introduce a new method for generating β-ketosulfides through direct coupling of readily available epoxides and thiols, which is catalyzed by an acridine-based PNP-type Ru(II)–pincer complex and liberates H₂ gas as a byproduct. The catalyst was found to promote both epoxide thiolysis to give a β-hydroxysulfide intermediate, and its subsequent dehydrogenation into the β-ketosulfide. The catalytic process exhibits product inhibition, leading to mixtures of β-ketosulfides and β-hydroxysulfides.