Influence of cation complexing solvent additives and functional groups in asymmetric alkylations of esters via lithium enolates

G Helmchen, A Selim, D Dorsch, I Taufer

Index: Helmchen, Guenter; Selim, Adel; Dorsch, Dieter; Taufer, Irmtraud Tetrahedron Letters, 1983 , vol. 24, # 31 p. 3213 - 3216

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Citation Number: 43

Abstract

Abstract Highly diastereoselective alkylations of propionates of chiral alcohols derived from (+)-camphor are described. It is demonstrated that steric shielding as well as cation complexation are important for stereoselection. The latter effects are in part rationalized on the basis of preferential formation of (Z)-or (E)-lithium enolates.