Process for the preparation of 6-chloro-2,4-dinitroaniline

US4613698A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Otto Arndt · Hofheim, DE
• Theodor Papenfuhs · Frankfurt, DE

Key dates

• Filing date: Feb 27, 1985
• Grant date: Sep 23, 1986
• Expiry date: Feb 27, 2005

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C209/74
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Process for the preparation of 6-chloro-2,4-dinitroaniline by chlorination of 2,4-dinitroaniline with sodium hypochlorite in water using acid, which comprises carrying out the chlorination in the presence of a mineral acid or strong organic acid at a pH value .ltoreq.0 and in the presence of a dispersing agent at temperatures of about 40.degree. to 50.degree. C. and, when the chlorination has ended, either (a) filtering the resulting acid aqueous dispersion hot and washing the filtered reaction product with hot aqueous alkali solution, or (b) initially rendering the resulting acid aqueous dispersion alkaline with aqueous alkali solution and then filtering the mixture hot and subsequently washing the filtered reaction product with hot dilute mineral acid.