§
Luxuse
Patent Intelligence
Sign In
← Back to Patent Explorer
US4122287A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of preparing 2,6-di-tert.butyl-4-methylphenol

Assignee: Individual
•
Filing: 1977-02-16
•
Granted: 1978-10-24
•
Expires: 1997-02-16
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

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° to 90° 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° to 140° 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° to 160° 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.

Inventors

  • 👤 Nina Vasilievna Zakharova
  • 👤 Alexandr Grigorievich Liakumovich
  • 👤 Jury Ivanovich Michurov
  • 👤 Zoya Stepanovna Shalimova

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 01:50
CPC Classifications
C; C07; C07C; C07C37/00; C07C37/50

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 147 words
A method of preparing 2,6-di-tert.butyl-4-methylphenol which comprises reacting 2,6-di-tert.butylphenol with formaldehyde and dimethylamine in a medium of an alcohol selected from the group consisting of methanol and ethanol at a temperature ranging from 80° to 90° C. with the formation of a reaction mass containing N,N-dimethyl-3,5-di-tert.butyl-4-hydroxybenzylamine and readily-volatile products, viz. an alcohol selected from the group containing methanol and ethanol, water and bis-amine; removing said readily-volatile products from the resulting reaction mass by heating thereof to a temperature ranging from 110° to 140° C. simultaneously with purging said reaction mass with an inert gas containing a secondary amine in an amount ranging from 5 to 50% by volume; contacting the remaining N,N-dimethyl-3,5-di-tert.butyl-4-hydroxybenzylamine with hydrogen at a molar ratio therebetween of 1:4-10 respectively on a hydrogenation catalyst at a temperature ranging from 120° to 160° C. with the formation of the desired product; and isolation of the latter.
Claim 2
Independent Claim 147 words
A method of preparing 2,6-di-tert.butyl-4-methylphenol which comprises reacting 2,6-di-tert.butylphenol with formaldehyde and dimethylamine in a medium of an alcohol selected from the group consisting of methanol and ethanol at a temperature ranging from 80° to 90° C. with the formation of a reaction mass containing N,N-dimethyl-3,5-di-tert.butyl-4-hydroxybenzylamine and readily-volatile products, viz. an alcohol selected from the group containing methanol and ethanol, water and bis-amine; removing said readily-volatile products from the resulting reaction mass by heating thereof to a temperature ranging from 110° to 140° C. simultaneously with purging said reaction mass with an inert gas containing a secondary amine in an amount ranging from 5 to 50% by volume; contacting the remaining N,N-dimethyl-3,5-di-tert.butyl-4-hydroxybenzylamine with hydrogen at a molar ratio therebetween of 1:4-10 respectively on a hydrogenation catalyst at a temperature ranging from 120° to 160° C. with the formation of the desired product; and isolation of the latter.
Claim 3
Dependent Claim 34 words
A method as claimed in claim 1, wherein as the inert gas use is made of a gas selected from the group consisting of hydrogen, nitrogen, helium, argon and C 1 -C 5 hydrocarbons.
Claim 4
Dependent Claim 27 words
A method as claimed in claim 1, wherein as the secondary amine use is made of an amine selected from the group consisting of dimethylamine and diethylamine.
Claim 5
Dependent Claim 21 words
A method as claimed in claim 1, wherein said inert gas contains 15 to 30% by volume of said secondary amine.

References Cited (Backward Citations)

US2882319A Cited
US2841624A Cited
US3845143A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-10-23 1982-04-24 1982-10-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-10-23 1986-04-24 1986-10-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-10-23 1990-04-24 1990-10-24 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag