Palladium-Catalyzed Direct Stereoselective Synthesis of Deoxyglycosides from Glycals
Abhijit Sau1, Ryan Williams1, Carlos Palo-Nieto1
1School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
Abstract:
Palladium(II) in combination with a monodentate phosphine ligand enables the unprecedented direct and α-stereoselective catalytic synthesis of deoxyglycosides from glycals. Initial mechanistic studies suggest that in the presence of N-phenyl-2-(di-tert-butylphosphino)pyrrole as the ligand, the reaction proceeds via an alkoxy palladium intermediate that increases the proton acidity and oxygen nucleophilicity of the alcohol. The method is demonstrated with a wide range of glycal donors and acceptors, including substrates bearing alkene functionalities.
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