The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 24, 1978
Filed:
Feb. 16, 1977
Nina Vasilievna Zakharova, Kazan, SU;
Alexandr Grigorievich Liakumovich, Kazan, SU;
Jury Ivanovich Michurov, Sterlitamak, SU;
Zoya Stepanovna Shalimova, Sterlitamak, SU;
Other;
Abstract
A method of preparing 2,6-di-tert.butyl-4-methylphenol comprising reacting 2,6-di-tert.butylphenol with formaldehyde and dimethylamine in a medium of methanol or ethanol at a temperature within the range of from 80.degree. to 90.degree. C to give a reaction mass containing N,N-dimethyl-3,5-di-tert.butyl-4-hydroxybenzylamine and readily-volatile products such as methanol or ethanol, water and bis-amine. The readily-volatile products are removed from the reaction mass by heating thereof to a temperature within the range of from 110.degree. to 140.degree. C simultaneously with purging the reaction mass with an inert gas containing a secondary amine in an amount of from 5 to 50% by volume. Thereafter, N,N-dimethyl-3,5-di-tert.butyl-4-hydroxybenzylamine is contacted with hydrogen at a molar ratio therebetween of 1:4-10 respectively on a hydrogenation catalyst at a temperature ranging from 120.degree. to 160.degree. C, to give the desired product which is then isolated. The method according to the present invention makes it possible to increase the desired product yield and improve quality thereof as compared to the prior art methods. The yield of the desired product is 98.7% as calculated per the starting raw materials. The method is technologically simple.