| 摘要 |
<p>1,212,474. Polyhalo - (sulphonic acid anilides). FARBENFABRIKEN BAYER A.G. 27 Feb., 1969 [1 March, 1968], No. 10539/69. Heading C2C. [Also in Division A5] The invention comprises polyhalo - (sulphonic acid anilides) of the formula wherein X is Cl when X<SP>1</SP> is H or X is H when X<SP>1</SP> is Cl, X<SP>11</SP> is H or Cl and Hal is Cl or Br. They may be obtained by reacting a sulphonic acid chloride of formula in the presence of an acid - binding agent with an aniline of formula Examples are given for the preparation of these compounds. They are useful as herbicides for combalting aquatic plants. 2 - Bromo - 3,5 - dichloroaniline is obtained by diazotizing 2,4 - dichloro - 6 - nitroaniline with nitrosylsulphuric acid and brominating with cuprous bromide and HBr to give 2 - bromo - 3,5- dichloro - 1 - nitrobenzene which is then reduced with H 2 in the presence of a hydrogenation catalyst to the required compound.</p> |
