Rhodium-catalyzed asymmetric arylation of N- and O-containing cyclic aldimines: facile and efficient access to highly optically active 3,4-dihydrobenzo[1,4] oxazin-2-ones and dihydroquinoxalinones

A highly enantioselective rhodium-catalyzed arylation of benzoxazinones and quinoxalinones with arylboroxines was realized for the first time by employing a simple sulfur-olefin as the ligand. This protocol provides an efficient access to chiral 3,4-dihydrobenzo[1,4] oxazin-2-ones and dihydroquinoxalinones with exceptionally high enantiomeric purity (up to 99.9% ee).