Various kinds of α-halo ketones readily reacted with disodium (dimercaptomethylene)malononitrile to give the corresponding 34-diamino-2,5-diacylthieno-[2,3-b]thiophenes in good to excellent yields. The reaction was successfully extended to the synthesis of a thienothiophene derivative having two sydnone rings by using the 4-(bromoacetyl)sydnone.