Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5225231 | Tetrahedron | 2007 | 10 Pages |
Abstract
Thermal reaction of 2-[N-(alk-2-enyl)benzylamino]-3-(2-substituted and 2,2-disubstituted)vinylpyrido[1,2-a]pyrimidin-4(4H)-ones gave azepine, the desired ene products, and/or pyran derivatives. The formation of the latter was responsible for the [4+2] cycloaddition reaction between the α,β-unsaturated ester carbonyl moiety as a diene part and the alkenylamino moiety as an ene one. The reaction features depended upon the kinds of substituents both on the vinyl and alkenyl counterparts; strongly electron-withdrawing substituents on the vinyl moiety or an electron-donating substituent on the alkenyl one changed the reaction feature from the ene reaction to the hetero Diels-Alder reaction.
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Related Topics
Physical Sciences and Engineering
Chemistry
Organic Chemistry
Authors
Michihiko Noguchi, Toshiya Sunagawa, Ryosuke Akao, Hisashi Yamada, Hidetoshi Yamamoto, Akikazu Kakehi,