Asymmetric Michael additions via SAMP-/RAMP-hydrazones anti-diastereo-and enantioselective synthesis of 3, 4-disubstituted 5-oxo-alkanoates

D Enders, K Papadopoulos, BEM Rendenbach…

Index: Enders, Dieter; Papadopoulos, Kyriakos; Rendenbach, Beatrice E.M.; Appel, Rolf; Knoch, Falk Tetrahedron Letters, 1986 ,  vol. 27,  # 30  p. 3491 - 3494

Full Text: HTML

Citation Number: 45

Abstract

An efficient and highly anti-diastereo-(de=90–≈100%) and enantioselective (ee=92–≈100% ) synthesis of 3,4-disubstituted 5-oxo-alkanoates in good overall chemical yields is described. The procedure involves the asymmetric Michael addition of aldehydes or ketones to enoates via their lithiated SAMP-/RAMP-hydrazones. Both enantiomers are accessible at will. ... The 1.4-addition of aldehydes and ketones to enoates in excellent asymmetric ...