INTRAMOLECULAR CYCLIZATION OF BETA-ALKYNYLPROPANAMIDES TO GAMMA-ALKYLIDENE-GAMMA-BUTYROLACTAMS

Authors
KOSEKI Y KUSANO S NAGASAKA T
Citation
Y. Koseki et al., INTRAMOLECULAR CYCLIZATION OF BETA-ALKYNYLPROPANAMIDES TO GAMMA-ALKYLIDENE-GAMMA-BUTYROLACTAMS, Tetrahedron letters, 39(21), 1998, pp. 3517-3520
Citations number
25
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
Tetrahedron letters → ACNP
ISSN journal
00404039
Volume
39
Issue
21
Year of publication
1998
Pages
3517 - 3520
Database
ISI
SICI code
0040-4039(1998)39:21<3517:ICOBTG>2.0.ZU;2-T
Abstract
A general method for the base-catalized intramolecular cyclization of beta-alkynylpropanamides 1 to gamma-alkylidene-gamma-butyrolactames 2 (and 3) was established. Reactions of beta-alkynylamides 1c-h, possess ing alkyl groups at the terminal acetylenes, in the presence of a cata lytic amount of LiN(TMS)(2)/AgOTf (= 2:1) in toluene gave exclusively (Z)-alkylidenelactames 2c-h in good yields. (C) 1998 Elsevier Science Ltd. All rights reserved.