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:
Feb. 11, 1986
Filed:
Jun. 04, 1982
Applicant:
Inventor:
Thomas R Opie, Collingswood, NJ (US);
Assignee:
Rohm and Haas Company, Philadelphia, PA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
549292 ;
Abstract
This invention relates to a novel process for the preparation of 4-hydroxy-6-methyl-2-pyrone which comprises reacting 3-acetyl-6-methyl-2(H)-pyran-2,4(3H)-dione (dehydroacetic acid, 'DHAA') with from 93% to about 99% sulfuric acid (1-7% water content) at temperatures from about 60.degree. to about 140.degree. C. under pressures from about 10 millimeters of mercury to about 75 pounds per square inch wherein the sulfuric acid to pyran weight ratio (H.sub.2 SO.sub.4 :DHAA) is from about 0.8:1 to about 3:1 and isolating the 4-hydroxy-6-methyl-2-pyrone.