Room Temperature Aerobic Peroxidation of Organic Substrates Catalyzed by Cobalt(III) Alkylperoxo Complexes
Yunzhou Chen, Hua‐Tian 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, CoIII(qpy)OOR supported by a planar tetradentate quaterpyridine ligand that can directly abstract H atoms from hydrocarbons (R′H) at ambient conditions (CoIII(qpy)OOR + R′H → CoII(qpy) + R′• + ROOH). The resulting alkyl radical (R′•) reacts rapidly with O2 to form alkylperoxy radical (R′OO•), which is efficiently scavenged by CoII(qpy) to give CoIII(qpy)OOR′ (CoII(qpy) + R′OO• → CoIII(qpy)OOR′). This unique reactivity enables CoIII(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.