Catalytic, nucleophilic allylation of aldehydes with 2-substituted allylic acetates: carbon-carbon bond formation driven by the water-gas shift reaction.

The ruthenium-catalyzed allylation of aldehydes with allylic acetates has been expanded to incorporate substituents at the 2-position of the allylic components. Allylic acetates bearing a variety of substituents (CO2-t-Bu, COMe, Ph, CH(OEt)2, and Me) undergo high-yielding additions with aromatic, α,β-unsaturated, and aliphatic aldehydes. The conditions of the reaction were found to be mild (75 °C, 24-48 h) and only required the use of 2-3 mol % of the triruthenium dodecacarbonyl catalyst under 40-80 psi of CO. The stoichiometries of water and allylic acetate employed were found to be critical to reaction efficiency.