Back to Search Start Over

Stereochemical control in the ester enolate Claisen rearrangement. 2. Chairlike vs boatlike transition-state selection

Authors :
Robert E. Ireland
Jia Ning Xiang
Peter Wipf
Source :
The Journal of Organic Chemistry. 56:3572-3582
Publication Year :
1991
Publisher :
American Chemical Society (ACS), 1991.

Abstract

The preference for chair- and boatlike transition-state geometries in the ester enolate Claisen rearrangement of straight chain, carbocyclic, and heterocyclic propanoates was investigated. A novel stereoelectronic effect in pyranoid and furanoid glycal systems leads to a significant relative stabilization of the boatlike vs the chairlike TS : . The preferred transition state in six- and five-membered carbocyclic systems is highly dependent on steric factors, as the energy difference between chair- and boatlike TS : tends to be small. With straight-chain substrates, a significant contribution of the boatlike TS : to the rearrangement product mixture is only expected in bis-donor substituted allylic esters

Details

ISSN :
15206904 and 00223263
Volume :
56
Database :
OpenAIRE
Journal :
The Journal of Organic Chemistry
Accession number :
edsair.doi...........452807663354e1a23e856af6cdc82f5b
Full Text :
https://doi.org/10.1021/jo00011a023