| 摘要 |
<p>is prepd. by catalytic hydrogenolysis of N,N-dimethyl-3,5-di-t-butyl-4-hydroxy benzylamine in the presence of a catalyst contg. Ni, Ti, Al, and using, as solvent, 2,6-di-t-butyl-4-methylphenol. The product is used as a stabiliser and anti-oxidant, e.g. for natural and synthetic rubber, polyethylene and polypropylene fibres, and food products. The known process above is carried out usually in an organic solvent e.g. decalin as in GB 1229480. However, in the reaction conditions, some resin is formed and the isolated product contains about 5% resin. The recovery of solvent is complicated and the product must be purified, e.g. by distillation, or crystallisation, for food uses. The above modification avoids any solvent recovery stage and gives a yield of product about 98.4%, which is satisfactory for food use without further purification.</p> |
