Fe(OTf)3-Catalyzed Aromatization of Substituted 3-Methyleneindoline and Benzofuran Derivatives: A Selective Route to C-3-Alkylated Indoles and Benzofurans

A simple and convenient approach was developed to the selective synthesis of 3-substituted indoles and benzofurans by the isomerization of 3-methyleneindoline and benzofuran derivatives catalyzed by Fe(OTf)(3). The salient features of this method are the easy availability of substrates, high yield, mild reaction conditions, tolerance of a variety of functional groups, and use of an environmentally friendly catalyst. A possible mechanism has also been proposed for the isomerization process.