Abstract Under microwave irradiation and solvent‐freeconditions, cyanoacetates (cyanoacetamides) react with ketones and sulphur in the presence of a small amount of morpholine to give 2‐amino‐thiophene‐3‐carboxylic derivatives. In particular, tetrahydro‐benzo[b]thiophene‐3‐carboxylic acid N‐aryl amides were synthesized in high yields of 84–95%.