| 摘要 |
<p>Prepn. of 2,6-di-tert. butyl-4-methylphenol (I) comprises reacting, 2,6-di-tert. butyl-phenol (II) with HCHO and dimethylamine (III) in (m)ethanol at 80-90 degrees C with formation of a reaction mass contg. N,N-dimethyl-3,5-di. tert. butyl-4-hydroxybenzylamine (IV) and readily-volatile prods. which are removed by heating to 110-114 degrees C and simultaneously purging with an inert gas mixt. contg. 5-50% amine. The purged mass contg. (IV) is then contacted with H2 at a ratio of 1:4-10 of (IV) to H2, on a hydrogenation catalyst at 120-160 degrees C, and (I) is isolated. (I) is useful as an antioxidant in petroleum prods., oils rubbers, plastics, and other polymers. (I) is also useful for stabilisation of animal feeds, and animal fats and polymeric materials of medicinal application, and also for treating certain cancerous diseases. Suitable catalysts are e.g. Pd-on-Carbon-Pd-on-alumina, etc. Sec. amines which can be used include dimethylamine, diethylamine, and suitable inert gases are e.g. H2, N2, Hl, Ar etc.</p> |
