A Hydrogenation/Oxidative Fragmentation Cascade for Synthesis of Chiral 4,5-Dihydro-1H-benzo[d]azepin-1-ones

An iridium-catalyzed asymmetric hydrogenation/oxidative fragmentation of 6 -substituted 5H-benzo [d] benzofuro[3,2-b]azepines has been developed, providing an efficient access to optically active 4-substituted 4,5-dihydro-1H-benzo[d]azepin-l-ones with up to 91% ee. A possible reaction pathway includes the asymmetric hydrogenation to furnish chiral cyclic amines and oxidative fragmentation under an air atmosphere..