Issue 21, 1975

On stereochemical preference in the SE2′ reaction

Abstract

Attempts are described to detect stereochemical preference during an SE2′ reaction in a synthetic model system. 7β-Deuterio-4,5-secocholest-5-en-4-al ethylene acetal (20d) cyclised with Lewis acid to give 7-deuterio-4α-(2-hydroxyethoxy)-5β-chloest-6-ene (23c) with complete retention of deuterium. By contrast, 7α-deuterio-4,5-secocholest-5-en-4-yl p-bromobenzenesulphonate (29c) cyclised in 2,2,2-trifluoroethanol to 5β-cholest-6-ene (31) with total loss of deuterium. In both cases there is a syn-relationship between the newly formed C–C bond and the allylic hydrogen atom that is lost. The implications of these findings for the SE2′ reaction are discussed.

Article information

Article type
Paper

J. Chem. Soc., Perkin Trans. 1, 1975, 2140-2149

On stereochemical preference in the SE2′ reaction

I. M. Cunningham and K. H. Overton, J. Chem. Soc., Perkin Trans. 1, 1975, 2140 DOI: 10.1039/P19750002140

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Spotlight

Advertisements