Journal of the American Chemical Society, Vol.133, No.20, 7664-7667, 2011
Asymmetric Synthesis of Methylenetetrahydrofurans by Palladium-Catalyzed [3+2] Cycloaddition of Trimethylenemethane with Aldehydes - A Novel Ligand Design
The palladium-catalyzed [3 + 2] cycloaddition of trimethylenemethane (TMM) with aldehydes is a direct and efficient route to methylenetetrahydrofurans. Herein we describe the first asymmetric synthesis of methylenetetrahydrofurans utilizing a palladium - TMM complex in the presence of a novel phosphoramidite ligand possessing a stereogenic phosphorus. The method allows for the formation of chiral disubstituted tetrahydrofurans in good yields and enantioselectivities.