Synthesis of Indoles via Ring Closure of 2-Alkylnitroaniline Derivatives.

Article abstract of DOI:10.1016/S0040-4020(01)87932-1

A variety of nitroindoles have been prepared from imidate, amidine, and sec-anilide derivatives of 2-alkyl-3- or 5-nitroanilines by a base-induced cyclization promoted by dialkyl oxalates.It is shown that essentially the same procedure also can be used to synthesize the corresponding nitroindole-3-glyoxylates in one simple operation.The synthetic potential is discussed and a mechanism is proposed.