Preparation of 2-Amino-5-homoallylfurans via Palladium-Catalyzed Tandem Cycloisomerization/Heck-Type Coupling of Homoallenyl Amides with Allyltrialkylsilanes
cycloisomerization/Heck-type coupling between homoallenyl amides and allyltrialkylsilanes, using a novel DDQ/MnO2 combination as the efficient oxidant. The reaction exclusively affords γ-allylation products in good to excellent yields with broad substrate scope under exceptionally mild reaction conditions. It represents one of the rare examples of the Pd-catalyzed intermolecularHeck-type coupling of allytrialkylsilanes
Enantioenriched tertiary and quaternary α-chiral allylsilanes have been obtained by metal-free asymmetric allylic alkylation of γ-substituted primary allylic bromides with primary alkyl Grignard reagents activated by a chiral Alexakis-type NHC ligand.