Oxetanes are important developing 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 approach to access numerous modes of radical reactivity by way of oxetane ring opening. The created system entails formation of an alkylated Co-complex intermediate from vitamin B12 and oxetane. Homolytic cleavage from the Co-C bond generates nucleophilic radicals that engage in reactions with SOMOphiles and low-valent transition metals. The scope with the developed reactions is broad with several functional groups being nicely tolerated. Importantly, the regioselectivity of those processes complements recognized methodologies. 29166-72-1 web 2089649-86-3 Chemical name PMID:24238102