| 摘要 |
A process for the preparation of a 2-aminobenzothiazol of the formula ( I ) <IMAGE> (I) in which R1 and R2 independently of each other are hydrogen, fluorine, chlorine, bromine or iodine, trifluoromethyl or C1-C4-alkyl, C1-C4-alkoxy or nitro groups, by conversion of an arylthiourea of the formula (II) <IMAGE> (II) in which R1 and R2 have the meaning mentioned, which comprises carrying out the conversion in 99 to 100% strength of sulfuric acid with continuous addition of catalytic amounts of bromine, hydrogen bromide or bromide in the form of aqueous solutions and using an arylthiourea of the formula (II) which contains 1 to 35% water.
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