Neighboring effect by heteroaromatic rings: Formation of skeletally rearranged adducts by cycloaddition reaction of norbornadiene-fused pyridazines and pyrazines with 4-phenyl-1,2,4-triazole-3,5(4H)-dione

Citation
T. Kobayashi et al., Neighboring effect by heteroaromatic rings: Formation of skeletally rearranged adducts by cycloaddition reaction of norbornadiene-fused pyridazines and pyrazines with 4-phenyl-1,2,4-triazole-3,5(4H)-dione, TETRAHEDRON, 55(46), 1999, pp. 13179-13192
Citations number
31
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry & Analysis","Organic Chemistry/Polymer Science
Journal title
TETRAHEDRON
ISSN journal
0040-4020 → ACNP
Volume
55
Issue
46
Year of publication
1999
Pages
13179 - 13192
Database
ISI
SICI code
0040-4020(19991112)55:46<13179:NEBHRF>2.0.ZU;2-8
Abstract
Norbornadiene-fused pyridazines and pyrazines reacted with 4-phenyl-1,2,4-t riazole-3,5(4H)-dione to give skeletally rearranged adducts in moderate yie lds. A similar reaction with fused pyridazine N-oxides or a fused pyrazine N-oxide resulted in the regioselective formation of the rearranged adduct. The formations of the skeletally rearranged adducts would be ascribed to th e intervention of bridged heteroarenium ion intermediates formed by the nei ghboring group participation of heteroaromatic rings. (C) 1999 Elsevier Sci ence Ltd. All rights reserved.