Photoredox-catalyzed coupling of acyl oxime acetates with thiophenols to give arylthioesters in water at room temperature

Photoredox catalysis in water has been receiving increasing attention due to its merits of being environment friendly, inexpensive, and safe. However, efficient approaches to arylthioesters via photoredox catalysis in water remain unknown. We herein report an environmentally responsible synthesis of arylthioesters through the coupling of acyl oxime acetates with thiophenols. This protocol was achieved in water with Eosin Y as the organophotocatalyst, MPEG-550 as the phase-transfer catalyst, and blue light. Preliminary mechanistic studies suggested a radical-radical coupling of an acyl radical with a thiyl radical. A convenient synthesis of valuable arylthioesters via visible-light-induced radical coupling of acyl oxime acetates with thiophenols in water was developed.