ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Activative Influence of the Nitro Group in the Cyclization Reactions of the Addition Products of 2-Chloro- 5-nitrobenzoyl Isothiocyanate with the Amines and 2-Propanol

D. Koščík, P. Kutschy, M. Dzurilla, and N. Mazánek

Department of Organic Chemistry, Faculty of Natural Sciences, P. J. Šafárik University, CS-041 67 Košice

Abstract: Reaction of 2-chloro-5-nitrobenzoyl isothiocyanate with the primary and secondary alkyl- and arylamines, as well as with 2-propanol yields corresponding thioureas, or O-isopropyl monothiocarbamate, respectively. Heating of these thioureas in dimethylformamide with LiH or in the benzene solution of triethylamine leads to formation of the cyclization products, i.e. the corresponding 2-alkyl(aryl)amino-6-nitro-4H-1,3-benzothiazin-4-ones.2-Thioxo-6-nitro-2,3-dihydro-4H-1,3-benzothiazin-4-one can be obtained by the reaction of 2-chloro-5-nitrobenzoyl isothiocyanate with sodium hydrogen sulfide. The synthesized benzothiazines are stable, their heating or melting does not lead to the rearrangement into the benzopyrimidinic heterocycles.

Full paper in Portable Document Format: 466a405.pdf

Chemical Papers 46 (6) 405–409 (1992)