Highly stereoselective intramolecular Michael addition using alpha-sulfinyl vinyllithium as an unprecedented Michael donor

Citation
N. Maezaki et al., Highly stereoselective intramolecular Michael addition using alpha-sulfinyl vinyllithium as an unprecedented Michael donor, ORG LETT, 3(1), 2001, pp. 29-31
Citations number
27
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Organic Chemistry/Polymer Science
Journal title
ORGANIC LETTERS
ISSN journal
1523-7060 → ACNP
Volume
3
Issue
1
Year of publication
2001
Pages
29 - 31
Database
ISI
SICI code
1523-7060(20010111)3:1<29:HSIMAU>2.0.ZU;2-4
Abstract
[GRAPHICS] The first example of an asymmetric intramolecular Michael addition reaction using cr lithiated vinylic sulfoxide as a Michael donor is reported. Micha el addition of the alpha -lithiated vinylic sulfoxide to (Z)-enoates procee ds with high diastereoselectivity to give the adducts having a stereogenic center with (R)-configuration at the beta -position of the ester in the cyc lopentene ring formation. The selectivity was reversed in the six-membered ring formation. On the other hand, the corresponding (E)-enoates provided M ichael adducts with poor diastereoselectivity.