Stereoselective Borane Reduction of Acetophenone using 1,3,2-Oxazaborolidine Derived from (R)-4-(Diphenylhydroxymethyl)-1,3-Thiazolidine
作者:Monique Calmes、Francoise Escale
DOI:10.1080/00397919908086109
日期:1999.4
Abstract A new chiral 1, 3, 2-oxazaborolidine derived from (R)-4-(diphenylhydroxymethyl)-l, 3-thiazolidine has been synthesized and its efficiency in the asymmetric reduction of acetophenone by borane has been investigated. It gives (R)-l-phenylethanol with high enantiomeric excess
Sulfur-containing β-amino alcohols as catalysts in enantioselective synthesis
作者:Wilhelm Trentmann、Thomas Mehler、Jürgen Martens
DOI:10.1016/s0957-4166(97)00193-6
日期:1997.6
Oxazaborolidine catalysts generated in situ from cyclic or acyclic sulfur containing (R)-cysteine, (S)-penicillamine and (S)-methionine derivates and BH3 have been applied successfully to the enantiocontrolled, catalytic reduction of aromatic ketones. The corresponding sec alcohols could be obtained in excellent enantiomeric excess, up to 100% ee. Using these chiral auxiliaries in the enantioselective addition of diethylzinc to aldehydes afforded optically active sec alcohols in enantiomeric excess up to 93% ee. (C) 1997 Elsevier Science Ltd.