Metal-Free C-H Functionalization and Aromatization Sequence for the Synthesis of 1-(Indol-3-yl)carbazoles and Total
Ganapathy Ranjani1, Rajagopal Nagarajan1
1School of Chemistry , University of Hyderabad , Hyderabad 500046 , India.
Abstract:
An operationally simple, metal-free, cost-effective, and mild oxidative cross-coupling protocol for the synthesis of 1-indolyl tetrahydrocarbazoles to afford 1-(indol-3-yl)carbazoles is developed. N-Chlorosuccinimide is used as a mild oxidant for the functionalization of the 1-position of tetrahydrocarbazoles, aromatization of which furnished 1-(indol-3-yl)carbazoles in good to moderate yields without employing protection/deprotection strategy. A naturally rare dibromo 1-(indol-3-yl)carbazole alkaloid was synthesized for the first time in two steps with an overall yield of 64% by applying the same methodology.
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