Regioselective Copper-Catalyzed Acylsilylation of Allenes Using Acyl Fluorides.

We report the copper-catalyzed acylsilylation of allenes using acyl fluorides. Under CuOAc/PCy3 catalysis, a broad range of aromatic acyl fluorides, allenes, and silylboranes undergo efficient three-component coupling to furnish β-silyl-β,γ-unsaturated ketones bearing sterically congested quaternary carbon centers. Control experiments indicate that acyl fluorides play a crucial role in promoting productive coupling, whereas less reactive acyl derivatives favor competing silaboration pathways.