Hetero-Diels-Alder Reaction with Indoloquinones.
作者:Roland BARRET、Nathalie ROUE、H. FILLION
DOI:10.1248/cpb.46.548
日期:——
The hetero Diels-Alder reaction of 4, 7-indoloquinones with crotonaldehyde dimethylhydrazone afforded 5-methyl-5, 6-dihydropyrido[6, 5-b]indole-4, 9-dione ([1, 8] isomer) and 5-methyl-5, 6-dihydropyrido[5, 6-b]indole-4, 9-diones ([1, 5] isomer). The 6, 7, 8, 9-tetrahydrocarbazole-2, 5-dione region-selectively afforded 4-methyl-1, 4, 6, 7, 8, 9-hexahydropyrido[2, 3-b]carbazole-5, 11-dione. The regiochemistry of these reactions was controlled by the substitution of the nitrogen and the 2-C atom of the indole moiety : the unsubstituted quinones afforded the [1, 8] regioisomer, whereas the [1, 5] compounds were obtained with the quinones bearing an electron-withdrawing substituent on the nitrogen or the 2-C atom.
4, 7-吲哚醌与巴豆醛二甲基腙的杂环 Diels-Alder 反应可得到 5-甲基-5, 6-二氢吡啶并[6, 5-b]吲哚-4, 9-二酮([1, 8]异构体)和 5-甲基-5, 6-二氢吡啶并[5, 6-b]吲哚-4, 9-二酮([1, 5]异构体)。6,7,8,9-四氢咔唑-2,5-二酮区域选择性地得到 4-甲基-1,4,6,7,8,9-六氢吡啶并[2,3-b]咔唑-5,11-二酮。这些反应的区域化学受控于吲哚分子的氮和 2-C 原子的取代:未取代的醌类化合物可得到[1, 8]区域异构体,而醌类化合物的氮或 2-C 原子上带有一个抽电子取代基时,则可得到[1, 5]化合物。