A thiol substrate-promoted one-pot synthesis of a library of heteroaromatic compounds was developed. Benzo[d]oxazole, benzo[d]thiazole, benzo[d]imidazole, oxazolo[4,5-b]pyridine and naphtho[2,3-d]oxazole derivatives were obtained under metal-free and external oxidant-free conditions in moderate to excellent yields. Commercially available substrates and the absence of supplemental catalysts, oxidants or additives make this method both practical and efficient.