REAGENT CONTROL IN THE ALDOL ADDITION-REACTION OF CHIRAL BORON ENOLATES WITH CHIRAL ALDEHYDES - TOTAL SYNTHESIS OF (3S,4S)-STATINE

Boron enolates bearing menthone-derived chiral ligands are capable of fair to excellent diastereocontrol in their reactions with chiral alde hydes. Thioester-derived (better than ketone derived) enolates are abl e to control aldol stereochemistry irrespective of the aldehyde prefer ences. With thioacetate-derived chiral enolates and enantiopure N,N-di benzyl alpha-amino aldehydes, either the 3,4-anti or the 3,4-syn aldol adduct can be obtained with very high diastereoselectivity just by ch anging the chiral boron ligand configuration. The above procedure was used for a stereoselective total synthesis of (3S, 4S)-statine. (C) 19 97 Elsevier Science Ltd.