Dimethylformamide → 3-chloro-2-(3-(trifluoromethyl)-1H-pyrazol-1-yl)pyridine

Participants

Reaction Conditions

Reaction Steps

1.72 kg (10.75 mol) of the raw 3-trifluoromethylpyrazole obtained in step a), 1.75 kg (11.83 mol) of 2,3-dichloropyridine and 4.73 kg of dimethyl formamide were charged to a reaction vessel. 2.97 kg (21.50 mol) of potassium carbonate were added, the mixture was heated to 120° C. with stirring and kept at 120-125° C. for further 3 h. The reaction mixtures was cooled to 25° C. and poured into 20 l of water. The thus obtained mixture was extracted twice with 5 L of tert.-butylmethyl ether. The combined organic phases were washed with 4 l of water and then evaporated to dryness. Toluene was added and the mixture was again evaporated to dryness. Thereby, the 2.7 kg of the title compound was obtained (purity >75% as determined by GC; yield 81.5%). The product can be purified by distillation.

Provenance & Evidence