Conjugate Addition of Indoles to &i&α,β&/i&-Unsaturated Ketones Using Bismuth (III) Bromide

摘要

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.