Coreactant Strategy for the Photoredox Catalytic Generation of Trifluoromethyl Radicals under Low-Energy Photoirradiation.
Photoredox catalysis has emerged as a valuable alternative to dark-state catalysis. For the full potential of photoredox catalysis to be utilized, it is imperative to make use of low-energy photons in photoinduced radical processes. We have demonstrated that the use of oxalate as a coreactant provides a useful principle for the photocatalytic production of trifluoromethyl radicals (•CF3) from CF3I upon green or red LED photoirradiation of narrow-bandgap photocatalysts. The photocatalytic cycle involves a radical anion of carbon dioxide (CO2(•-)) as a reductant for CF3I, which is generated through photoinduced oxidative decarboxylation of oxalate. Electrochemical characterizations and steady-state and transient photophysical investigations were performed to reveal that there are two photoinduced electron-transfer pathways for oxalate-mediated •CF3 generation.
Sinheui
S
Kim
Gyurim
G
Park
Department of Chemistry, Chung-Ang University , Seoul 06974, Republic of Korea.
Eun Jin
EJ
Cho
Youngmin
Y
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