Process for the preparation of chlorohydroxyanilines

摘要

The present invention relates to a process for the preparation of compounds of the general formula I <IMAGE> in which either R<1> is H or Cl and R<2> is NH2 or R<1> is NH2 and R<2> is Cl, by catalytic hydrogenation of a compound of the general formula II <IMAGE> in which either R<3> is H or Cl and R<4> is NO2 or R<3> is NO2 and R<4> is Cl, in an organic solvent, the process being characterised in that the catalyst used is a sulphited platinum-on-carbon catalyst, the hydrogenation is carried out at temperatures from 20 to 100@C and, after the reaction has ended, the reaction mixture is heated to the boiling point of the solvent to isolate the product.