Formation of oxadiazolo[4,5‐<i>a</i>]indolines <i>via</i> addition reactions of cycloalkano[<i>b</i>]indoles with nitrile oxides. Crystal structure of an adduct

Abstract

Abstract Reactions of stable nitrile oxides with cycloalkano[ b ]indoles gave as main product adducts 3 containing the oxadiazolo[4,5‐ a ]indoline ring system. The structure elucidation of the isolated adducts was based on their spectral data, chemical behaviour and in one case the structure was confirmed by crystallographic X‐ray analysis. The mechanism of the reaction is also discussed.