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