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:
Nov. 27, 1979
Filed:
Oct. 27, 1978
Applicant:
Inventor:
Sharad S Sathe, Maryland Heights, MO (US);
Assignee:
Mallinckrodt, Inc., St. Louis, MO (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
260575 ;
Abstract
The preparation of p-aminophenol by the catalytic hydrogenation of nitrobenzene in an acid reaction medium containing an aqueous isopropyl alcohol solution of trimethyldodecylammonium chloride leads to the formation of chloro- and isopropoxyaniline impurities. These end up in the by-product aniline. The substitution of dimethyldodecylamine sulfate for the quaternary salt eliminates these impurities without significant adverse effect on the yield, production rate or purity of the p-aminophenol.