Fully Automated Continuous Flow Synthesis of Highly Functionalized Imidazo1,2-a Heterocycles

The first continuous flow synthesis of imidazo1,2-apyridine-2-carboxylic acids directly from 2-aminopyridines and bromopyruvic acid has been developed, representing a significant advance over the corresponding in-flask method. The process was applied to the multistep synthesis of imidazo1,2-apyridine-2-carboxamides, including a Mur ligase inhibitor, using a two microreactor, multistep continuous flow process without isolation of intermediates.