Stereoselective intramolecular cyclization of allyl and homoallyl benzamide via pi-allylpalladium complex catalyzed by Pd(0)

Citation
Ky. Lee et al., Stereoselective intramolecular cyclization of allyl and homoallyl benzamide via pi-allylpalladium complex catalyzed by Pd(0), J ORG CHEM, 64(26), 1999, pp. 9450-9458
Citations number
103
Language
INGLESE
art.tipo
Review
Categorie Soggetti
Chemistry & Analysis","Organic Chemistry/Polymer Science
Journal title
JOURNAL OF ORGANIC CHEMISTRY
ISSN journal
0022-3263 → ACNP
Volume
64
Issue
26
Year of publication
1999
Pages
9450 - 9458
Database
ISI
SICI code
0022-3263(199912)64:26<9450:SICOAA>2.0.ZU;2-S
Abstract
The transformation of acyclic allylic benzamides 4 and homoallylic benzamid es 12 to vinyl oxazolines 3 is achieved in the presence of base by the cata lysis of Pd(0) in high yield and with high diastereoselectivity. Especially , in the case of homoallylic benzamides 12, trans-oxazolines 3 are formed e xclusively or predominantly over cis-oxazolines 8, irrespective of the comp osition of their stereoisomers. The reaction is believed to proceed via the same pi-allylpalladium complex that arises from either primary or secondar y allylic acetates. We applied this method to the syntheses of beta-amino-a lpha-hydroxy acids 1 and gamma-amino-beta-hydroxy acids 2, conveniently pro tected as oxazoline.