Rh2(II)-Catalyzed Nitro-Group Migration Reactions: Selective Synthesis of 3-Nitroindoles from β-Nitro Styryl Azides
摘要:
Rhodium carboxylate complexes (1 mol %) catalyze the migration of electron-withdrawing groups to selectively produce 3-substituted indoles from beta-substituted styryl azides. The relative order of migratorial aptitude for this transformation is ester << amide < H < sulfonyl < benzoyl << nitro.
afforded fused indoles such as indolo[3,2-c]quinolin-6-ones, pyrido[4,3-b]indol-1-ones and other similar compounds in moderate to high yields via cyclization-ring expansion reactions. The photolytic process was much more facile than the thermal process and could be further improved by addition of CuI.
Cu-Catalyzed Cascade Annulation of Alkynols with 2-Azidobenzaldehydes: Access to 6<i>H</i>-Isochromeno[4,3-<i>c</i>]quinoline
作者:Xiao-Feng Mao、Xiao-Ping Zhu、Deng-Yuan Li、Pei-Nian Liu
DOI:10.1021/acs.joc.7b00937
日期:2017.7.7
A copper-catalyzedcascade reaction of alkynols and 2-azidobenzaldehydes has been achieved, giving 6H-isochromeno[4,3-c]quinoline in yields of 40–81%. This reaction provides a novel, concise strategy for rapidly constructing compounds with fused N- and O-containing heterocycles. In contrast to previously reported reactions of alkynols in which the first step is intramolecular cycloisomerization, the
铜催化的炔醇和2-叠氮基苯甲醛的级联反应已经实现,得到6 H-异色酚[4,3- c ]喹啉,产率为40-81%。该反应提供了一种用于快速构建化合物与稠合的N A新颖,简洁策略-和O -含有杂环。与先前报道的炔醇的反应第一步是分子内环异构化相反,炔醇的这种新反应的第一步是熵不利的分子间加成。然后将所得的半缩醛中间体进行分子内环化和芳构化以提供产物。
One-Pot Synthesis of Indolo[2,3-c]quinolin-6-ones by Sequential Photocyclizations of 3-(2-Azidophenyl)-N-phenylacrylamides
作者:Wei Zhang、Zhanshan Li、Weixia Wang、Xiaotian Zhang、Congcong Hu
DOI:10.1055/s-0032-1317703
日期:——
A one-pot synthesis of indolo[2,3-c]quinolin-6(7H)-ones was achieved by sequential photocyclizations of 3-(2-azidophenyl)-N-phenylacrylamides in moderate to high yields. The reactions proceeded via photochemical cyclization of aryl azides to form N-phenylindol-2-carbamides and subsequent 6 pi-electrocyclic reaction and oxidative aromatization to afford the corresponding indolo[2,3-c]quinolin-6(7H)-ones.