Process for the preparation of para-nitroso-diphenylhydroxylamines

US4129740A · kind A · utility

Assignee

• Akzona Incorporated · US

Inventors

• Hans Zengel · Kleinwallstadt, DE
• Manfred Bergfeld · Zell am Harmersbach, DE

Key dates

• Filing date: Jan 30, 1978
• Grant date: Dec 12, 1978
• Expiry date: Jan 30, 1998

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D211/46
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

An improved process for the preparation of para-nitroso-diphenylhydroxylamines is disclosed. One member of the group consisting of nitrosobenzene, ortho-substituted nitrosobenzenes, meta-substituted nitrosobenzenes, ortho-meta-disubstituted nitrosobenzenes and para-substituted nitrosobenzenes is reacted with one member selected from the group consisting of nitrosobenzene, ortho-substituted nitrosobenzenes, meta-substituted nitrosobenzenes, and ortho-meta-disubstituted nitrosobenzenes, in the presence of an acid catalyst. The improvement comprises utilizing as the acid catalyst an acid selected from the group consisting of aliphatic, cycloaliphatic, and aromatic sulfonic acids, having a pK.sub.a equal to or less than one, perchloric acid, and trifluoroacetic acid, in an amount equal to or greater than 0.5 mol of acid per mol of nitroso reactants, and performing the reaction at a temperature from about -20.degree. C to about 60.degree. C.