Rhodium-Catalyzed Highly Enantioselective Addition of Arylboronic Acids to Cyclic Aldimines: Practical Asymmetric Synthesis of Cyclic Sulfamidates

A highly efficient asymmetric arylation of cyclic N-sulfonyl aldimines with arylboronic acids catalyzed by a rhodium/sulfur-olefin ligand complex under mild conditions is described. A wide range 4-aryl-3,4-dihydro-1,2,3-benzoxathiazine 2,2-dioxides were obtained in extremely high yields (93-99%) and high enantiomeric purities (97-99% ee).