Preparation of sparingly soluble aromatic amines by catalytic hydrogenation of the corresponding aromatic nitro compounds in the presence of hydrogen, a solvent and a catalyst having a particle size of not less than 0.5 mm, wherein the aromatic nitro compound selected is a compound whose corresponding amine is soluble to an extent of not more than 50% by weight in the solvent used under the reaction conditions of the hydrogenation, and also their use for preparing azo compounds.