Conjugate addition of hydroxylamines to 4-substituted butenolides

Authors
Panfil, I Abramski, W Chmielewski, M
Citation
I. Panfil et al., Conjugate addition of hydroxylamines to 4-substituted butenolides, J CARB CHEM, 17(9), 1998, pp. 1395-1403
Citations number
33
Categorie Soggetti
Chemistry & Analysis
Journal title
JOURNAL OF CARBOHYDRATE CHEMISTRY
ISSN journal
07328303 → ACNP
Volume
17
Issue
9
Year of publication
1998
Pages
1395 - 1403
Database
ISI
SICI code
0732-8303(1998)17:9<1395:CAOHT4>2.0.ZU;2-N
Abstract
4-Substituted-butenolides treated with free hydroxylamine at pH=5 undergo c onjugate addition - rearrangement to afford isoxazolidin-5-ones. This is in contrast to N-substituted hydroxylamines which under the same conditions p roduce Michael adducts only. In the presence of base, butenolides undergo r acemization via flat tautomeric forms.