STEREOCHEMICAL CONTROL IN THE ESTER ENOLATE CLAISEN REARRANGEMENT .1. STEREOSELECTIVITY IN SILYL KETENE ACETAL FORMATION

被引：285

作者：

IRELAND, RE

WIPF, P

ARMSTRONG, JD

机构：

[1] Department of Chemistry, University of Virginia, Charlottesville, Virginia 22901, McCormick Rd.

来源：

JOURNAL OF ORGANIC CHEMISTRY | 1991年 / 56卷 / 02期

关键词：

D O I：

10.1021/jo00002a030

中图分类号：

O62 [有机化学];

学科分类号：

070303 ; 081704 ;

摘要：

Methods for the stereoselective deprotonation and silylation of esters were systematically investigated. A kinetically controlled enolization in combination with a kinetic resolution process accounts for the selective formation of (E)- and (Z)-silyl ketene acetals in THF and THF/dipolar solvent systems with bases such as LDA, LHMDS, and KHMDS. A thermodynamic equilibration mechanism seems to be of minor significance with ester enolates. Improved reaction conditions were exemplified in a highly stereoselective Claisen rearrangement in THF/45% DMPU.

引用

页码：650 / 657

页数：8

共 64 条

[61] THERMODYNAMIC RESULTS FOR GEOMETRICAL ISOMERISM IN SILYL KETENE ACETALS [J].