A DIASTEREOSELECTIVE RADICAL CYCLIZATION APPROACH TO PYROGLUTAMATES

Authors
GOODALL K PARSONS AF
Citation
K. Goodall et Af. Parsons, A DIASTEREOSELECTIVE RADICAL CYCLIZATION APPROACH TO PYROGLUTAMATES, Tetrahedron letters, 38(3), 1997, pp. 491-494
Citations number
38
Categorie Soggetti
Chemistry Inorganic & Nuclear
Journal title
Tetrahedron letters → ACNP
ISSN journal
00404039
Volume
38
Issue
3
Year of publication
1997
Pages
491 - 494
Database
ISI
SICI code
0040-4039(1997)38:3<491:ADRCAT>2.0.ZU;2-8
Abstract
The 5-endo radical cyclisation of pyruvic acid derived dehydroalanines which contain chiral ester auxiliaries is reported. Cyclisation of th e menthol ester derivative using Bu(3)SnH at 80 degrees C proceeded wi th low diastereoselectivity (1.75:1) but the selectivity could be incr eased to 6:1 on cyclisation of the corresponding 8-phenylmethyl ester at 20 degrees C. Copyright (C) 1996 Elsevier Science Ltd