Method for producing substituted pyrazoles

US6229022A · kind A · utility

Assignee

• BASF SE

Inventors

• Hans Rupert Merkle · Ludwigshafen, DE
• Erich Fretschner · Neckarsteinach, DE

Key dates

• Filing date: Dec 13, 1999
• Grant date: May 8, 2001
• Expiry date: Dec 13, 2019

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D231/12
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Pyrazole derivatives are prepared by reacting carbonyl compounds R.sup.1 --C(O)--CH(R.sup.2)--CH.sub.2 R.sup.3 with hydrazine, its hydrate or its salts in 30 to 100% by weight sulfuric acid in the presence of catalytic amounts of iodine or of an iodine compound.