A Novel C-C Single-Bond Formation Accompanying C-O Bond Cleavage by Use of a Ketone, an Alkylating Reagent, and a Low-Valent Vanadium Complex in the Presence of a Catalytic Amount of Molecular Oxygen.

A C-C single-bond-forming reaction from ketones with accompanying C-O bond cleavage mediated by a RMgBr or RLi-vanadium(II)-O(2) system has been accomplished. Different from conventional reductive coupling reactions of ketones such as the McMurry coupling, the present method forms a C-C single (instead of a double) bond and yields a product that contains components derived from the ketone and the alkylating reagent in a one-pot reaction. Collaboration of both a low-valent vanadium(II) species and a higher-valent vanadium species produced from vanadium(II) and a catalytic amount of O(2) effects the abstraction of the oxygen atom from a C-O bond.