1,2-NUCLEOPHILIC ADDITIONS OF ORGANOLITHIUM REAGENTS TO CHIRAL OXIME ETHERS

Chiral oxime ethers are readily prepared from chiral alkoxyamines deri ved from ephedrine and norephedrine. These chiral oxime ethers of isob utyraldehyde and benzaldehyde undergo 1,2-nucleophilic addition reacti ons with alkyllithium reagents (n-BuLi, PhLi and n-BuLi,tert-butyllith ium, respectively) to afford the chiral alkoxyamines with a diastereom eric excess of 64-88%. Reduction of the alkoxyamines with LiAlH4 gave the corresponding chiral amines. The diastereoselectivity of the react ion appears to directly mirror the E:Z ratio of the starting oxime eth ers.