Process for preparing 2-(aminomethylidene)-4,4-difluoro-3-oxobutyric esters

US8592578B2 · kind B2 · utility

Assignee

• BASF SE

Inventors

• Thomas Zierke · Böhl-Iggelheim, DE
• Volker Maywald · Ludwigshafen, DE
• Michael Rack · Eppelheim, DE
• Sebastian Peer Smidt · Mannheim, DE
• Michael Keil · Freinsheim, DE
• Bernd Wolf · Niederkirchen, DE
• Christopher Koradin · Ludwigshafen, DE

Key dates

• Filing date: Oct 17, 2012
• Grant date: Nov 26, 2013
• Expiry date: Oct 17, 2032

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D295/145
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for preparing difluoromethyl-substituted pyrazol-4-ylcarboxylic acids and their esters, 2-(aminomethylidene)-4,4-difluoro-3-oxobutteric esters of the formula (I)in which R1, R2 and R3 independently of one another are C1-C6-alkyl, C1-C6-haloalkyl, C2-C6-alkenyl, C3-C10-cycloalkyl or benzyl or NR2R3 is a 5- to 10-membered heterocyclic radical, to a process for preparing compounds of the formula (I) wherein an appropriate 3-aminoacrylic ester is reacted with difluoroacetyl fluoride and to the use of compounds of the formula (I) in the process for preparing difluoromethyl-substituted pyrazol-4-ylcarboxylic acids and their esters.