Process for the manufacture of 4-nitro-4'-amino-diphenylamine-2-sulfonic acid and 2-nitro-4'-amino-diphenylamine-4-sulfonic acid

US4254054A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Otto Arndt · Hofheim, DE
• Wolfgang Tronich

Key dates

• Filing date: Oct 11, 1979
• Grant date: Mar 3, 1981
• Expiry date: Oct 11, 1999

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C309/46
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

4-Nitro-4'-amino-diphenylamine-2-sulfonic acid, 2-nitro-4'-amino-diphenylamine-4-sulfonic acid and their sodium salts are obtained in good yield and high purity by condensing 6- or 4-chloro-3-nitro-benzene sulfonic acid and 1,4-phenylene diamine in a saturated aqueous sodium chloride solution. The products and their desulfonation derivatives are dye precursors.