Thermally Induced Cyclization of Electron-Rich N-Arylthiobenzamides to Benzothiazoles

Abstract

Heating N-(2-methoxyphenyl)benzenecarbothioamides in refluxing nitrobenzene for 24 hours gives the corresponding benzothiazoles with intramolecular ipso substitution of the ortho-methoxy­ substituent. The thermal cyclization of various other N-arylthiobenzamides is also explored.

Key words

cyclizations - heterocycles - thioamides

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