Batch and flow synthesis of sulfides and sulfoxides using green solvents and oxidant through visible-light photocatalysis

Herein, we report an environmentally friendly, one-pot, scalable method for the synthesis of sulfides and sulfoxides via photocatalyzed C-C bond-formation and oxidation. Employing mild photoredox conditions, green solvents, and oxygen as the oxidant, the approach is sustainable and efficient. The integration of a microreactor-based flow system enabled large-scale production, addressing the typical scalability issues of photocatalytic and liquid-gas phase reactions. Mechanistic studies confirmed that C-C bond formation occurs via an α-thiomethyl radical through a single-electron transfer (SET) pathway, while oxidation involves both SET and energy transfer (EnT) mechanisms.