Acyclic Diastereoselection via Claisen Rearrangement with Boron Enolates. Chelation Control of Enolate Geometry

Taeboem Oh; Zbigniew Wrobel; Paul N. Devine

doi:10.1055/s-1992-21274

Synlett 1992; 1992(1): 81-83
DOI: 10.1055/s-1992-21274

letter

© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.

Acyclic Diastereoselection via Claisen Rearrangement with Boron Enolates. Chelation Control of Enolate Geometry

Taeboem Oh^* , Zbigniew Wrobel, Paul N. Devine

^*Department of Chemistry, State University of New York, Binghamton, New York 13902-6000, USA

Abstract

PDF Download All articles of this category

The Ireland-Claisen rearrangement of a variety of O-protected 2-butenyl glycolates via chelated boron and tin triflates to give after esterification methyl 2-methoxy/benzyloxy-3-methyl-4-pentenoates is described. Diastereoselectivities as high as 99.5% were observed. The rates of rearrangement involving boron enolates are higher than those involving silyl ketene acetals or lithium enolates.

PDF (177 kb)