Catalytic hydrogenation process for preparing pyrazoles

US10975036B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Eric George Klauber · Bad Dürkheim, DE
• Michael Rack · Eppelheim, DE
• Sebastian Soergel · Ludwigshafen, DE
• Birgit Gockel · Ludwigshafen, DE
• Roland Goetz · Ludwigshafen, DE

Key dates

• Filing date: Jan 25, 2017
• Grant date: Apr 13, 2021
• Expiry date: Jan 25, 2037

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D403/12
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a catalytic process for preparing pyrazoles of formula V comprising the step of cyclizing hydrazone substituted α,β-unsaturated carbonyl compounds by reacting them with hydrogen in a reaction mixture comprising as components (a) a hydrogenation catalyst, (b) an acid selected from Brønsted acids, ammonium salts of Brønsted acids, and Lewis acids, (c) a protic solvent, and optionally (d) an aprotic solvent.