Process for the preparation of Zafirlukast and analogs thereof

摘要

The present invention relates to a process for the preparation of (1-alkylindol-3-ylmethyl) benzoic acid derivatives, in particular Zafirlukast and analogs thereof. Further, this process is based on protection group free and C—H bond activation strategy involving all step catalytic transformation sequence and comprises the following steps: Sonogashira coupling, indole formation by Sp³ C—H activation, reductive hydrogenation and amidation.