Synthesis of substituted 3-cyano- and 3-(arenesulfonyl)indoles from o-nitrobenzyl cyanides and sulfones

Article abstract of DOI:10.1055/s-0030-1289515

Formation of enamines, in the reaction of o-nitrophenyl-acetonitriles with Vilsmeier reagents, followed by reductive cyclization using Zn in acetic acid, leads to variously substituted 3-cyanoindoles, possessing aryl, alkyl, and aminoalkyl substituents at C-2. The method, when starting from the appropriate o-nitrobenzylsulfones, allows the synthesis of substituted 3-(arenesulfonyl)- indoles. Georg Thieme Verlag Stuttgart · New York.