Novel synthesis of thiazolo/thienoazepine-5,8-diones from dihalo cyclic 1,3-diketones and mercaptonitrile salts

An efficient approach to thiazolo[4,5-b] azepine-5,8-diones and thieno [3,2-b] azepine-5,8-diones has been developed via a domino synthesis of multifunctionalized thiazoles/thiophenes and further intramolecular cyclization. This transformation proceeded rapidly under mild conditions without use of metal catalyst.