A Novel Synthesis of 1-Nosyl 3,3-Dichloro-β-Lactams and Derivatives

Rhodium-Catalyzed Tandem Asymmetric Allylic Decarboxylative Addition and Cyclization of Vinylethylene Carbonates with N-Nosylimines

A enantioselective tandem transformation, concerning asymmetric allylic decarboxylative addition and cyclization of N-nosylimines with vinylethylene carbonates (VECs), in the presence of [Rh(C2H4)2Cl]2, chiral sulfoxide-N-olefin tridentate ligand has been developed. The reaction of VECs with various substituted N-nosylimines proceeded smoothly under mild conditions, providing highly functionalized oxazolidine frameworks in good to high yields with good to excellent enantioselectivity.

Organocatalytic Enantioselective Synthesis of α-Fluoro-β-amino Acid Derivatives

Asymmetric cyclocondensation of N-sulfonylimines with fluoroacetic acid promoted by isothiourea catalyst HBTM-2 generates 3-fluoro-β-lactams with high enantio- and diastereoselectivity. These reactive compounds are opened with alcohols or amines to produce the corresponding α-fluoro-β-amino acid derivatives in moderate yields.