Diastereoselective Addition Reactions of Furyl Sulfonylimine Using Chiral Boronates as Auxiliary:  Application to the Enantioselective Synthesis of 2,3-Disubstituted Furyl Sulfonylamides^†

The addition reactions of various nucleophiles to a furyl sulfonylimine bearing a chiral boronate at the C-3 position furnished chromatographically separable diastereomers. The R diastereoselection was found to be more favorable. Further transformation of C−B bonds to C−C bonds was achieved by using standard Suzuki coupling conditions to give optically active 2,3-disubstituted furyl sulfonylamides.