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.
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