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Synlett 2008(3): 410-412  
DOI: 10.1055/s-2007-1000875
LETTER
© Georg Thieme Verlag Stuttgart · New York

A Novel One-Pot Synthesis of N-Acylindoles from Primary Aromatic Amides

Mohammed Abid , Omar De Paolis, Béla Török*
Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Blvd, Boston, MA 02125, USA
Fax: +1(617)2876030; e-Mail: bela.torok@umb.edu;
Further Information

Publication History

Received 10 September 2007
Publication Date:
21 December 2007 (online)

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Abstract

A novel one-pot synthesis of N-acylindoles via tandem cycloalkylation-annelation is described. This approach is based on the use of a strong solid-acid catalyst, montmorillonite K-10, and microwave irradiation under solvent-free conditions. The tandem cycloalkylation of amides and annelation of intermediate pyrroles were completed in minutes and provided good yields with high selectivities for the indoles. The safe, easy to handle catalyst, and the convenience of the product isolation make this process an attractive, environmentally benign alternative for the synthesis of N-acylindoles.

Keywords

amides - solid-acid catalysis - microwave heating - N-acylindole

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