Highly stereoselective syntheses involving N-alkyl-4,4,7.alpha.-trimethyl-trans-octahydro-1,3-benzoxazine intermediates. 2

Previously studied highly stereoselective additions of Grignard, organolithium, and hydride reagents to the 2-benzoyl derivative of compound 1a have been extended to other 2-alkanoyl derivatives (1,R'=methyl, ethyl, isopropyl) and to the 2-benzoyl derivative with R=methyl. High diastereoselectivity is attained in most of the products