Automated Multistep Continuous Flow Synthesis of 2-(1H-Indol-3-yl)thiazole Derivatives

Abstract

The multistep continuous flow assembly of 2-(1H-indol-3-yl)thiazoles using a Syrris AFRICA^® synthesis station is reported. Sequential Hantzsch thiazole synthesis, deketalization, and Fischer indole synthesis provides rapid and efficient access to highly functionalized, pharmacologically significant 2-(1H-indol-3-yl)thiazoles. These complex drug-like small molecules are generated in reaction times of less than 15 minutes and in high yields (38–82% over three chemical steps without isolation of intermediates).

Key words

heterocycles - indoles - condensation - tandem reactions - microreactor - microfluidic synthesis

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