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. 18, 1986
Filed:
Jul. 25, 1983
Douglas C Caskey, O'Fallon, MO (US);
Douglas W Chapman, St. Louis, MO (US);
Mallinckrodt, Inc., St. Louis, MO (US);
Abstract
A process for preparing unsubstituted and alkyl substituted p-aminophenols. A charge mixture is prepared comprising an unsubstituted or alkyl substituted nitrobenzene, a highly dissociated acid, a catalyst containing platinum and a divalent sulfur compound in which sulfur is bonded to two other moieties, the sulfur compound being present in a proportion of between about 0.1 and about 100 moles per gram-atom of platinum. The mixture comprises an organic phase containing the substrate and an aqueous phase containing the acid. Hydrogen is introduced into the mixture at a pressure of 0-50 psig while the mixture is agitated at a temperature of 70.degree. C. to 100.degree. C., thereby causing the substrate to be reduced to phenylhydroxylamine or an alkyl substituted phenylhydroxylamine. The hydroxylamine is rearranged in the presence of acid to the substituted or unsubstituted p-aminophenol, which is recovered from the aqueous phase.