Preparation of amine salts of 4-nitrotoluene-2-sulfonic acid

US6160169A · kind A · utility

Assignee

• BASF SE

Inventors

• Rudolf Bermes · Ludwigshafen, DE
• Armin Haag · Hirschberg, DE
• Hellmut Kast
• Peter Krotzsch · Ketsch, DE

Key dates

• Filing date: Dec 7, 1998
• Grant date: Dec 12, 2000
• Expiry date: Dec 7, 2018

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C09B23/148
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for preparing amine salts of 4-nitrotoluene-2-sulfonic acid by sulfonation of nitrotoluene with oleum, subsequent dilution of the reaction mixture with water and extraction with lipophilic amines, wherein the acidic aqueous solution of the sulfonation product is partially neutralized with mineral bases. The compounds prepared according to the invention are particularly suitable for preparing dyes.