Trifluoroacetic acid → 5-Chloro-3-(4-methoxy-3-methylphenyl)-1,4-dimethyl-1H-pyrazole

Participants

Reaction Steps

At 0° C., a mixture of 5-chloro-4-formyl-3-(4-methoxy-3-methyl-phenyl)-1-methyl-1H-pyrazole (described in Reference Preparation example 91) 0.3 g and trifluoroacetic acid 10 ml was added trimethylsilane 0.27 g. The resulting mixture was stirred at room temperature for three hours, and thereto was added water 5 ml. The resulting mixture was extracted with ethyl acetate. The organic layer was washed with water and was dried over anhydrous magnesium sulfate, and was then concentrated under reduced pressure. The resulting residue was subjected to a silica gel column chromatography to give 5-chloro-3-(4-methoxy-3-methyl-phenyl)-1,4-dimethyl-1H-pyrazole 0.28 g.

Provenance & Evidence