作者:István Hermecz、Annamária Molnár、Ferenc Faigl、Benjamin Podányi、Zoltán Finta、László Balázs
DOI:10.3987/com-09-11746
日期:——
4-diones. The latters formed from N-(2-pyridyl)iminoketenes, the common intermediates of 4H-pyrido[1,2-a]pyrimidin-4-one and 1,8-naphthyridin-4-ones, via a "head-to-tail" [4+2] cycloaddition. 3-Halo-4H-pyrido[1,2-a]pyrimidin-4-ones were obtained from 4H-pyrido[1,2-a]pyrimidin-4-one with N-halosuccinimides. The structures of the new compounds were characterized by means of 1 H NMR and 13 C NMR examinations
卤代 4H-pyrido[1,2-a]pyrimidin-4-one 是通过异亚丙基 (2-pyridylamino) 亚甲基丙二酸酯的热环化和脱羧合成的,由 2-氨基吡啶和原位形成的异亚丙基甲氧基亚甲基丙二酸酯制备。代替 4H-pyrido[1,2-a]pyrimidin-4-ones,6-氯和 6-溴衍生物提供 7-halo-1,4-dihydro-1,8-naphthyridin-4-ones 和1-(6-卤代-2-吡啶基)-3-[(6-卤代-2-吡啶基氨基)亚甲基]-1,2,3,4-四氢吡啶-2,4-二酮。后者由 N-(2-pyridyl)iminoketenes、4H-pyrido[1,2-a]pyrimidin-4-one 和 1,8-naphthyridin-4-ones 的常见中间体通过“头对- tail" [4+2] 环加成。3-Halo-4H-pyrido[1,2-a]pyrimidin-4-ones