PREPARATION OF 4,4a,9,9a-TETRAHYDROCARBAZOLES AND 1,3a,4,8b-TETRAHYDROCYCLOPENTA[<i.b</i>]INDOLES

Abstract

Halocyclization of mesylates or tosylates of 2-(cycloalk-2-en-1-yl)anilines gives N-methanesulfonyl-  or N-toluenesulfonyl-1-halo-1,2,3,4,4a,9a-hexahydrocarbazoles, heating of which in DMF at 160°C  or  in piperidine  at  110°C leads to 4,4a,9,9a-tetrahydro-3H-carbazoles. Heating N-methanesulfonyl-1-iodo-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indole in DMF at 180-200°C gives 1,3a,4,9b-tetrahydrocyclopenta[b]indole, while in the presence of an ortho–methyl  substituent  the dehydroiodination reaction proceeds in piperidine at 110°C in high yield. The effect of the nature of the ortho substituent of N-methyl-1-iodo-1,2,3,3a,4,8b-hexahydrocyclopenta[b]indole on the conformational equilibrium of the cyclopentane ring has been established by 1H NMR spectroscopy.

How to Cite
Gataullin, R. R.; Ishberdina, R. R.; Shitikova, O. V.; Minnigulov, F. F.; Spirikhin, L. V.; Abdrakhmanov, I. B.  Chem. Heterocycl. Compd. 2006, 42, 1025. [Khim. Geterotsikl. Soedin. 2006, 1184.]

For this article in the English edition see DOI 10.1007/s10593-006-0199-7