Rhodium catalyzed direct C3-ethoxycarbonylmethylation of imidazo[1,2-a]pyridines with ethyl diazoacetate

Abstract An efficient and environment-friendly C3-ethoxycarbonylmethylation of imidazo[1,2-a]pyridines with ethyl diazoacetate in the presence of a Rh(II) catalyst was developed. Such strategy not only enables the synthesis of zolpidem, but also provides a way to generate synthetic intermediates to afford cellular active anticancer agents.