Organic heterocyclothiazenes. Part 8. 7-Amino-1,3,5,2,4,6-trithiatriazepine and related compounds

Abstract

7-Aminotrithiatriazepine (9) is prepared from the 7-methoxycarbonyl derivative (3) through the corresponding hydrazide, acyl azide, and isocyanate. It is a stable crystalline compound, readily acylated and alkylated on the exocyclic nitrogen atom, but is very sensitive to aqueous acid. 7-Bromo- and 7-iodo-trithiatriazepine are prepared from the carboxylic acid by treatment with the halogen and mercuric oxide under u.v. irradiation; the halogen atoms are inert to nucleophilic displacement. The spectroscopic properties of trithiatriazepines, which are now fairly predictable, are summarised. Trithiatriazepine-7-carboxamide (10) is N-acetylated in high yield under mild neutral conditions with dinitrogen tetraoxide in acetonitrile.