Fig. 4. Scope of the photochemical synthesis of 2-thiopyrrolidinone.

^aReaction conditions B: 1 (0.4 mmol), 2 (0.2 mmol), PTH4 (5 mol%), and degassed toluene (2 mL) under argon with irradiation of LEDs (λ_max = 390 nm) with 100% intensity at 30–35 °C for 24 h. ^bisolated yield. ^cfor gram scale reaction.