Ag(i)/(S,S)-ip-FOXAP catalyzed diastereo- and enantioselective 1,3-dipolar cycloaddition of azomethine ylides with benzosultam-3-ylidenes†
Abstract
The AgOAc/ip-FOXAP complex catalyzed the highly diastereo- and enantioselective 1,3-dipolar cycloaddition of azomethine ylides with benzosultam-3-ylidenes to give a single isomer of the exo-cycloadduct in good yield. For azomethine ylides, the presence of the Cα-substituted group enables its coordination to the silver center, which is of dramatic importance for the asymmetric reaction yield and for tuning the exo-diastereoselection.