Radical Ring-Opening of Oxetanes Enabled by Co-Catalysis

Oxetanes are valuable building blocks due to their well-explored propensity to undergo ring-opening reactions with diverse nucleophiles. However, their application as precursors of radical species remains unexplored. Herein, we present a cobalt catalysis-based strategy to access various modes of radical reactivity via oxetane ring opening. The developed method involves formation of an alkylated Co-complex intermediate from vitamin B12 and oxetane. Homolytic cleavage of the Co-C bond generates nucleophilic radicals that engage in reactions with SOMOphiles and low-valent transition metals. The scope of the developed reactions is broad with various functional groups being well tolerated. Importantly, the regioselectivity of these processes complements known methodologies.