Reactions of N- and C-alkenylanilines: VIII. Synthesis of functionalized cycloalka[b]indoles from o-(Cycloalk-2-en-1-yl)anilines

• Published in: Russian journal of organic chemistry Vol. 43; no. 9; pp. 1310 - 1321
• Main Authors: Gataullin, R. R., Likhacheva, N. A., Suponitskii, K. Yu, Abdrakhmanov, I. B.
• Format: Journal Article
• Language: English
• Published: NEW YORK Springer Nature 01.09.2007
• Subjects: Chemistry; Chemistry, Organic; Physical Sciences; Science & Technology; POLAR CROSSOVER REACTIONS; DESIGN
• ISSN: 1070-4280; 1608-3393
• DOI: 10.1134/S1070428007090096

N-Acyl-2-(cyclohex-2-en-1-yl)anilines react with molecular iodine to give the corresponding N-acyl-1-iodo-1,2,3,4,4a,9a-hexahydrocarbazoles which undergo isomerization into 1-R-2a,3.4,5,5a.10a-hexahydro[1,3]oxazolo[5,4,3-j,k]carbazol-10-ium iodides; no isomerization occurs with N-acetyl-3-iodo-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indole. The reaction of N-p-tolylsulfonyl-3,4,4a,9a-tetrahydrocarbazoles with hydrogen peroxide leads to the formation of a single 1,2-epoxy derivative with trans orientation of the nitrogen- and oxygen-containing rings. N-p-Tolylsulfonyl-1,3a,4,8b-tetrahydrocyclopenta[b]lndoles give rise to the corresponding 2,3-epoxy derivatives with both trans and cis orientation of the dihydropyrrole and oxirane fragments. The resulting epoxides undergo trans-opening with formation of N-p-tolylsulfonyl-1- hydroxy-2-methoxy-1,2,3,4,4a,9a-hexahydrocarbazoics and N-p-tolysulfonyl-3-hydroxy-2-methoxy- 1,2,3,3a,4,8b-hexahydrocyclopenta[b]indoles on heating in methanol in the presence of KU-2 cation exchanger. Mutual orientation of the oxirane and nitro-en-containina rin-s in the epoxides derived from cyclopenta[b]indoles was proved by X-ray analysis.