Tetrahedron

Synthese stereoselective d'esters α, β-ethyleniques α-methyles Z ou E par la reaction de wittig-horner a partir de phosphonates ou d'oxydes de phosphine

G Etemad-Moghadam, J Seyden-Penne

Index: Etemad-Moghadam, Guita; Seyden-Penne, Jacqueline Tetrahedron, 1984 , vol. 40, # 24 p. 5153 - 5166

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Citation Number: 39

Abstract

The reaction of α-branched aldehydes with diethyl 1-carbomethoxyethyl phosphonate 1b in THF/nBuLi at low temperature leads stereoselectively to Z α-methyl α, β-unsaturated esters. From a linear aldehyde, the reaction is less stereoselective, while from α, β-unsaturated ones, the E isomers are predominantly formed in good yields. From diphenyl 1- carbomethoxyethyl phosphine oxide 2b, E α-methyl α, β-unsaturated esters are ...