Synthesis of substituted esters of imidazoles, oxazoles, thiazoles, and diethyl pyrazine-2,5-dicarboxylate from a common acyclic precursor employing C-formylation strategy

A novel synthetic route to substituted esters of imidazoles, oxazoles, thiazoles, and diethyl pyrazine-2,5-dicarboxylates via C-formylation of glycine ethyl ester hydrochloride is reported. This methodology is simple, robust, and gives good yields of different heterocyclic esters in one or two steps from a common acyclic precursor and is amenable to large scale synthesis.