CHIRAL 6,7-DIHYDROOXEPIN-2(5H)-ONES AND THE AZEPINONE ANALOGUES : CONFORMATION AND DIASTEREOFACIAL SELECTIVITY IN ADDITION TO THE ENONES

Abstract Diastereofacial selectivity in addition to the enones of 6-and 7-substituted dihydrooxepinones was studied. The addition occurred preferentially from the face anti to the substituent and 7-substituted substrates showed higher diastereofacial selectivity than the 6-substituted substrates. An explanation for the observed diastereofacial selectivity is proposed.