PREPARATION OF 4,5-DIHYDRODITHIENO3,4-B:3',4'- EAZEPINE-5,9-DIONE

摘要

ABSTRACT OF THE DISCLOSURE:A novel process for the preparation of 4,5-dihy-drodithieno[3,4-b:3',4'-e]azepine-5,9-dione is described,which process comprises the cyclization reaction of an esterof the formula IV: IVwhere n is 0, 1 or 2 and R1 and R2 are identical ordifferent and are each C1-C4-alkyl, or, where n is 0, R1 andR2, together with the carbon atoms to which they are bonded,form a benzene nucleus.