PREPARATION OF 2-VINYLINDOLINE DERIVATIVES BY OXIDATIVE CYCLIZATION OF 2-ALKENYLANILINES
DOI:
https://doi.org/10.1007/616Keywords:
1-acyl-2-vinylindolines, tetrahydrocarbazole, tetrahydrocyclopenta[b]indole, metal complex catalysis, oxidative cyclizationAbstract
Derivatives of 4,4a,9,9a-tetrahydrocarbazole, 1,3a,4,8b-tetrahydrocyclopenta[b]indoline, (2R*,3S*)-1‑acetyl-3-methyl-2-vinylindoline, and also a mixture of (2R*,3S*)- and (2R*,3R*)-3‑methyl-2-vinyl-indolines were obtained by refluxing N-acyl-2-(cycloalk-2-en-1-yl)- or N-acyl-2-(1-methylbut-2‑en-1‑yl)anilines with Pd(OAc)2 in a toluene–pyridine mixture bubbled with air. From 2‑(cyclopent-2-en-1‑yl)-4-methylaniline under these conditions, 7-methyl-1,3a,4,8b-tetrahydrocyclopenta[b]indole was formed. Its reaction with allyl bromide gave 4-allyl-7-methyl-1,3a,4,8b-tetrahydrocyclopenta[b]indole in good yield.
Authors: G. G. Mazgarova, D. A. Skladchikov, V. P. Nikolaev, and R. R. Gataullin
English Translation in Chemistry of Heterocyclic Compounds, 2013, 49 (5), pp 689-697