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Indexed by:期刊论文

Date of Publication:2014-09-01

Journal:SYNLETT

Included Journals:SCIE、Scopus

Volume:25

Issue:15

Page Number:2155-2160

ISSN No.:0936-5214

Key Words:cinchona alkaloid; organocatalysis; enantioselectivity; beta-keto esters; industrial application

Abstract:A highly efficient alpha-hydroxylation of beta-keto esters catalyzed by cupreidine in the presence of cumyl hydroperoxide (CHP) was achieved. The reaction was applied to a wide variety of beta-keto esters to give products in high yields (up to 95%) with excellent enantioselectivities (up to 97% ee). The reaction had been successfully scaled up to a gram quantity and (S)-5-chloro-2-hydroxy-1-oxo-2,3-dihydro-1H-indene-2-carboxylate - the important intermediate of Indoxacarb were obtained in 96% yield with 86% ee. The enantiomeric excess could be improved to 99% by crystallization, and this method has prospect of industrial application for its advantages of enantioselectivity, ease of catalyst preparation and reclamation of catalyst.