A powerful new stereo-controlled method for epoxidation of electrophilic alkenes
作者:Carol Clark、Patricia Hermans、Otto Meth-Cohn、Clive Moore、Heinrich C. Taljaard、Gerda van Vuuren
DOI:10.1039/c39860001378
日期:——
tetrahydrofuran are shown to epoxidise α,β-unsaturated esters and sulphones efficiently in a stereo- and regio-specific manner, while esters of chiral alcohols undergo diastereofacially selective epoxidation.
A process for producing an optically active 2-hydroxybutyric ester (1), characterized by including reacting an optically active 2,3-epoxybutyric ester (2) with a thiol in the presence of scandium trifluoromethanesulfonate or ytterbium trifluoromethanesulfonate, to thereby produce Compound (3), and subjecting Compound (3) to desulfurization reaction:
(wherein R represents a C1 to C6 alkyl group or a C7 or C8 aralkyl group; R
1
represents a C1 to C12 alkyl group or a phenyl group; and * represents S- or R-absolute configuration).
The present invention provides a process for producing an optically active 2-hydroxybutyric ester at high yield and high optical purity.
A process for producing an optically active 2-hydroxybutyric ester (1), characterized by including reacting an optically active 2,3-epoxybutyric ester (2) with a thiol in the presence of scandium trifluoromethanesulfonate or ytterbium trifluoromethanesulfonate, to thereby produce Compound (3), and subjecting Compound (3) to desulfurization reaction:
(wherein R represents a C1 to C6 alkyl group or a C7 or C8 aralkyl group; R1 represents a C1 to C12 alkyl group or a phenyl group; and * represents S- or R-absolute configuration). The present invention provides a process for producing an optically active 2-hydroxybutyric ester at high yield and high optical purity.