Published on Journal of The American Chemical Society (3 September 2021)

Author(s): Yunzhou Chen, Huatian Shi, Chi-Sing Lee, Shek-Man Yiu, Wai-Lun Man*, Tai-Chu Lau*

Abstract

Room temperature aerobic oxidation of hydrocarbons is highly desirable and remains a great challenge. Here we report a series of highly electrophilic cobalt(III) alkylperoxo complexes, Co^III(qpy)OOR supported by a planar tetradentate quaterpyridine ligand that can directly abstract H atoms from hydrocarbons (R′H) at ambient conditions (Co^III(qpy)OOR + R′H → Co^II(qpy) + R′^• + ROOH). The resulting alkyl radical (R′^•) reacts rapidly with O₂ to form alkylperoxy radical (R′OO^•), which is efficiently scavenged by Co^II(qpy) to give Co^III(qpy)OOR′ (Co^II(qpy) + R′OO^• → Co^III(qpy)OOR′). This unique reactivity enables Co^III(qpy)OOR to function as efficient catalysts for aerobic peroxidation of hydrocarbons (R′H + O₂ → R′OOH) under 1 atm air and at room temperature.