GSCGreen and Sustainable Chemistry2160-6951Scientific Research Publishing10.4236/gsc.2019.93005GSC-93713ArticlesChemistry&Materials Science Conjugate Addition of Indoles to <i>α,β</i>-Unsaturated Ketones Using Bismuth (III) Bromide TylerJ. Rauwolf1ZhijiaGeng1ZacharyP. Kinney1JaredL. Renfroe1JackH. Roireau1LaurenT. Yep1RamS. Mohan1*Laboratory for Environmentally Friendly Organic Synthesis, Department of Chemistry, Illinois Wesleyan University, Bloomington, IL, USA180720190903798410, June 201915, July 2019 18, July 2019© Copyright 2014 by authors and Scientific Research Publishing Inc. 2014This work is licensed under the Creative Commons Attribution International License (CC BY). http://creativecommons.org/licenses/by/4.0/

An efficient method for the conjugate addition of indoles to a variety of chalcones using BiBr 3 in ethanol (190 proof) is reported. Products are isolated by a simple procedure that avoids an aqueous work up and extensive chromatography, thus minimizing waste. Bismuth (III) compounds are especially at tractive from a green chemistry perspective because they are remarkably nontoxic, non-corrosive and relatively inexpensive.

Bismuth Bismuth Bromide Conjugate Addition Green Chemistry IndolesAcknowledgements

This material is based upon work supported by the National Science Foundation under CHE-1229133, which funded the purchase of a 400 MHz NMR spectrometer. RM would like to acknowledge an Artistic and Scholarly grant from Illinois Wesleyan University.

Conflicts of Interest

The authors declare no conflicts of interest regarding the publication of this paper.

Cite this paper

Rauwolf, T.J., Geng, Z.J., Kinney, Z.P., Renfroe, J.L., Roireau, J.H., Yep, L.T. and Mohan, R.S. (2019) Conjugate Addition of Indoles to α,β-Unsaturated Ketones Using Bismuth (III) Bromide. Green and Sustainable Chemistry, 9, 79-84. https://doi.org/10.4236/gsc.2019.93005

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