Stereoselective reduction of various α-keto esters 5a-d derived from exo-10,10-diphenyl-2,10-camphanediol 4a and exo-10,10-diphenyl-10-methoxy-2- camphanol 4b is described. High to excellent diastereomeric excess (99% de) with good chemical yields is obtained. The sense of stereoselectivity as a function of C10 modification is remarkable. Further, in the case of 5d, both diastereomers of α-hydroxyl esters can be obtained with excellent optical purity by the appropriate choice of reaction conditions. The influence of the solvents and additives on the reaction course has been investigated.
ASJC Scopus subject areas
- Organic Chemistry