Cr-catalyzed chiral allenone synthesisviasequential radical–polar crossover and Oppenauer oxidation

We describe the Cr-catalyzed enantioconvergent synthesis of chiral 2,3-allenones from aldehydes and propargyl bromides, which features an unprecedented cascade of Cr-catalyzed asymmetric reductive radical–polar crossover and Oppenauer oxidation.