FACILE SYNTHESIS OF INDOLELACTONES USING Mn(III)-BASED OXIDATIVE SUBSTITUTION-CYCLIZATION REACTION

摘要

Based on the oxidation of indole with Mn(OAc)(3) in the presence of 1,1-diarylethenes affording 3-vinyl-substituted indoles, a similar oxidation using indole-2-carboxylic acids was evaluated in order to effectively introduce the substituent group to the C-3 position of the indolecarboxylic acids. The coupling reaction followed by oxidative cyclization smoothly proceeded at room temperature in an AcOH-HCO2H mixed solvent to give the desired indolelactones in high yields. The reaction details, the structure determination of the products and a brief reaction mechanism are described.