Method for the production of 3-isopropyl-1H-2, 1,3-benzothiadiazine-4 (3H)-one-2,2-dioxide

US6252069A · kind A · utility

Assignee

• BASF SE

Inventors

• Hans Rupert Merkle · Ludwigshafen, DE
• Otto Worz · Friedelsheim, DE
• Erich Fretschner · Neckarsteinach, DE
• Hanspeter Hansen
• Albrecht Muller · Allschwil, CH
• Kurt Benz · Römerberg, DE

Key dates

• Filing date: Feb 17, 2000
• Grant date: Jun 26, 2001
• Expiry date: Feb 17, 2020

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D285/16
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for preparing 3-isopropyl-1H-2,1,3-benzothiadiazin-4 (3H)-one 2,2-dioxide (I) or a salt of I ##STR1## which comprises reacting anthranilic isopropylamide II ##STR2## simultaneously with sulfur trioxide or chlorosulfonic acid in the presence of an organic base or with adducts of sulfur trioxide and organic bases and phosphorus oxychloride at from 50.degree. C. to the reflux temperature, followed, if appropriate, by conversion into its salts, is described.