The first lateral functionalization of calix[4]arenes by a homologous anionic ortho-Fries rearrangement

Citation
O. Middel et al., The first lateral functionalization of calix[4]arenes by a homologous anionic ortho-Fries rearrangement, J ORG CHEM, 65(3), 2000, pp. 667-675
Citations number
36
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry & Analysis","Organic Chemistry/Polymer Science
Journal title
JOURNAL OF ORGANIC CHEMISTRY
ISSN journal
0022-3263 → ACNP
Volume
65
Issue
3
Year of publication
2000
Pages
667 - 675
Database
ISI
SICI code
0022-3263(20000211)65:3<667:TFLFOC>2.0.ZU;2-F
Abstract
Treatment of calix[4]arene bis-O-carbamates 4a,b-6a,b with LDA in THF resul ts in the regio-and stereoselective introduction of both axial and equatori al carboxamide groups at the methylene bridges via a homologous anionic ort ho-Fries rearrangement to give 7-16. The stereochemical outcome of the rear rangement is dependent on the reaction conditions and the conformation of t he starting material. Stereochemical and structural proof has been secured by the X-ray crystal structure of calix[4]arene 10 having only one equatori al carboxamide moiety. The use of this novel class of methylene bridge-func tionalized calix[4]arenes is illustrated by the formation of bis-gamma-lact one 19, while the enhanced acidity of the remaining hydroxyl groups, owing to the presence of axial carboxamide groups at the methine bridges, followe d from the easy propylation of bisrearranged calix[4]arene 7.