2-Aminobenzothiazole

2-Aminobenzothiazole is the organic compound with the formula. It is related to the parent benzothiazole, but with an amino group at the unique methyne position on the thiazole ring. As confirmed by X-ray crystallography, it is a planar molecule, which exists as the amine tautomer.
2-Aminobenzothiazoles are often prepared by cyclization of 2-bromo-substituted arylthioureas.
Isothiocyanic acid, which can be generated in situ from sodium thiocyanate, adds to anilines to also afford 2-aminobenzothiazoles. Many other methods are available.
Diazotization of 2-aminobenzothiazoles gives diazonium salts. These salts undergo azo coupling with anilines. In this way some are prepared some useful dyes such as Basic Blue 54.