Catalytic asymmetric addition of arylboronic acids to N-Boc imines generated in situ using C2-symmetric cationic N-heterocyclic carbenes (NHCs) Pd diaquo complexes

The catalytic asymmetric addition of arylboronic acids to N-Boc imines generated in situ from stable and easily prepared α-carbamoyl sulfones was realized by using chiral cationic C₂-symmetric N-heterocyclic carbene (NHC) Pd²⁺ diaquo complexes 1a-c as the catalysts, producing the corresponding adducts in good to high yields (up to 89%) and good to high enantioselectivities (up to 90% ee).