Alkylation of cycloalkano[<i>B</i>]indoles <i>via</i> indolylmagnesium salts: Synthesis of 3<i>h</i>‐indoles and oxidative rearrangement to spiro[cycloalkane‐1,2′‐indolin]‐3′‐ones

Abstract

Abstract Alkylation of cycloalkano[ b ]indolylmagnesium iodide with alkyl halides has been analyzed to prepare cycloalkano‐3 H ‐indoles, methyl and N,N ‐dimethylpropyl derivatives. Spiro[cycloalkane‐1,2′‐indolin‐3′‐one] derivatives appear as secondary products in this reaction. Selectivity and optimization of the reaction has been determined and a mechanism for the formation of the spiro derivative is proposed.