Concise, Gram-Scale Synthesis of Furo[2,3-B]pyridines, with Functional Handles for Chemoselective Cross-Coupling

A concise 4-step synthesis of furo[2,3-b]pyridines, with handles in the 3 and 5 positions for palladium mediated cross-coupling reactions, is described. The synthetic route has been optimized, with only one step requiring purification by column chromatography. The route is amenable to scaling-up and was successfully executed on a multi-gram scale. Furopyridines are of growing interest in medicinal chemistry, and this route should enable easy access to the core for structure-activity relationship (SAR) studies.