Abstract
The synthesis of benzo-1,2,4-dithiazines was investigated presuming a reversible sulfur-sulfur
bond formation. 2-Aminothiophenol, when allowed to react with isothiocyanates, provided
benzothiazoles. 2,2′-Diaminodiphenyl disulfide underwent cyclizations very readily
without any reducing agent to give, according to the reaction conditions, benzothiazoles
or benzo-1,2,4-dithiazines. The developed procedure offers a simple and convenient
way to prepare the title compounds in very good to excellent yields. Until now, benzo-1,2,4-dithiazines
as well as 2,2′-diaminodiphenyl disulfides bearing aminocarbonothioyl groups were
unknown.
Key words
benzo-1,2,4-dithiazines - benzothiazoles - cyclizations - heterocycles - sulfur