Silver-Catalyzed 1,3-Dipolar Cycloaddition of Azomethine Ylides with β-Boryl Acrylates
摘要:
The Ag-catalyzed 1,3-dipolar cycloaddition of (E)-beta-borylacrylates with azomethine ylides is described. The resulting 3-borylpyrrolidine derivatives were obtained in high yields and complete endo selectivities using AgOAc/dppe as catalyst system and B(dam) as boryl group. Transformation of the B(dam) group into pinacol borane and oxidation afforded 3-hydroxyproline derivatives in high yields.