Asymmetric spirocyclization: A new type of acid-catalyzed intramolecular 1,4-addition to form carba-spirocyclic compounds

Citation
S. Yamada et al., Asymmetric spirocyclization: A new type of acid-catalyzed intramolecular 1,4-addition to form carba-spirocyclic compounds, TETRAHEDRON, 54(51), 1998, pp. 15555-15566
Citations number
17
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry & Analysis","Organic Chemistry/Polymer Science
Journal title
TETRAHEDRON
ISSN journal
0040-4020 → ACNP
Volume
54
Issue
51
Year of publication
1998
Pages
15555 - 15566
Database
ISI
SICI code
0040-4020(199812)54:51<15555:ASANTO>2.0.ZU;2-H
Abstract
Novel spirocyclization based on intramolecular 1,4-addition and its asymmet ric version have been developed using a combination of Lewis acid and 1,2-d iol. Treatment of five- and six-membered alpha,beta-unsaturated cyclic keto nes having a 4-oxopentyl group at the beta-position with Lewis acid and eth ylene glycol gave spiro[4.5]decane-2,7-dione and spiro[5.5]undecane-2,8-dio ne, respectively. The asymmetric version of this reaction has been develope d by using optically active 1,2-diol such as cyclohexane-1,2-diol to afford the spirocyclic products of up to 85% e.e. (C) 1998 Elsevier Science Ltd. All rights reserved.