The Journal of Organic Chemistry

Asymmetric aldol reactions. Use of the titanium enolate of a chiral N-acyloxazolidinone to reverse diastereofacial selectivities

M Nerz-Stormes, ER Thornton

Index: Nerz-Stormes, Maryellen; Thornton, Edward R. Journal of Organic Chemistry, 1991 , vol. 56, # 7 p. 2489 - 2498

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Citation Number: 144

Abstract

Aldol reactions of the titanium enolate of (S)-N-propionyl-4-isopropyl-2-oxazolidinone (readily derived from L-valine) with representative aldehydes give high diastereofacial selectivities for the syn aldol adducts expected from chelation control. This represents a remarkable reversal in selectivity compared with the corresponding boron enolate, thus permitting either enantiomeric form of &hydroxy-a-methyl carboxylic acids to be made from ...