Highly regioselective Friedel–Crafts alkylation of indoles with α,β-unsaturated N-acylbenzotriazoles

doi:10.1016/j.tetlet.2006.03.110

Tetrahedron Letters

Volume 47, Issue 22, 29 May 2006, Pages 3767-3771

https://doi.org/10.1016/j.tetlet.2006.03.110 Get rights and content

Abstract

The Friedel–Crafts alkylation rather than acylation of indoles was realized with α,β-unsaturated acylbenzotriazoles catalyzed by samarium(III) iodide under reflux in anhydrous THF. The reaction was highly regioselective, and a series of new 3-substituted indole derivatives were obtained in moderate to good yields with the potential to be further transformed into various indole derivatives due to the presence of active acylbenzotriazole moiety.

Graphical abstract

The Friedel–Crafts alkylation rather than acylation of indoles was realized with α,β-unsaturated N-acylbenzotriazoles catalyzed by samarium(III) iodide under reflux in dry THF. The reaction was highly regioselective, and a series of new 3-substituted indole derivatives were obtained and could be further transformed into various indole derivatives due to the presence of active acylbenzotriazole moiety.

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Acknowledgement

We are grateful to Zhejiang Provincial Natural Science Foundation of China (Project No. Y405035) for financial support.

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Highly regioselective Friedel–Crafts alkylation of indoles with α,β-unsaturated N-acylbenzotriazoles

Abstract

Graphical abstract

Section snippets

Acknowledgement

ARKIVOC

J. Org. Chem.

J. Chem. Res. (s)

Synlett

Synlett

J. Org. Chem.