Abstract
A simple, economical, and environmentally friendly copper-catalysed direct oxidative C–N coupling of 2-aminopyridines with β-keto esters using air as oxidation agent for the creation of imidazo[1,2-a]pyridine-3-carboxylates is demonstrated. Imidazo[1,2-a]pyridine is the basic skeleton for a wide range of biological and pharmacological compounds.
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