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RESEARCH ARTICLE
Contents Vol 66(12)

Al(OTf)3 Catalysed Friedel-Crafts Michael Type Addition of Indoles to α,β-Unsaturated Ketones with PEG-200 as Recyclable Solvent

Mukut Gohain A , Jc Jacobs A , Charlene Marais A and Barend C. B. Bezuidenhoudt A B
+ Author Affiliations
- Author Affiliations

A Department of Chemistry, University of the Free State, PO Box 339, Bloemfontein 9300, South Africa.

B Corresponding author. Email: bezuidbc@ufs.ac.za

Australian Journal of Chemistry 66(12) 1594-1599 https://doi.org/10.1071/CH13254
Submitted: 14 May 2013  Accepted: 31 August 2013   Published: 6 November 2013

Abstract

An Al(OTf)3 catalysed efficient Friedel–Crafts Michael type addition of indoles to α,β-unsaturated ketones using recyclable PEG-200 as an alternative reaction solvent is disclosed. The reaction under microwave irradiation is clean, leads to excellent yields in minutes and reduces the use of volatile organic compounds.


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[32]  The crystallographic data for product 3el has been deposited at the Cambridge Crystallographic Data Centre as supplementary publication number CCDC 904909. Copies of the data can be obtained free of charge on application to CCDC, 12 Union Road, Cambridge, CB2 1EZ, UK.