Ammonium Chloride → 1-(1-Methyl-1H-pyrazol-5-yl)-3-[4-(trifluoromethyl)phenyl]prop-2-yn-1-one

Participants

Reaction Conditions

Reaction Steps

Methyl magnesium bromide (9.70 mL, 1.0 M tetrahydrofuran solution) was added dropwise to a tetrahydrofuran (4.0 mL) solution of 1-ethynyl-4-(trifluoromethyl)benzene (1.80 mL) under cooling in an ice bath, and the obtained solution was then stirred for 2 hours. Thereafter, the reaction solution was cooled to −78° C., and a tetrahydrofuran (6.2 mL) solution of N-methoxy-N,1-dimethyl-1H-pyrazol-5-carboxamide (867 mg) was then added thereto. The obtained mixture was stirred for 1 hour, and was then stirred for 2.5 hours under cooling in an ice bath. Thereafter, a saturated ammonium chloride aqueous solution was added to the reaction solution, and the obtained mixture was then extracted with ethyl acetate. The organic layer was washed with a saturated saline, and was then dried over anhydrous magnesium sulfate, followed by vacuum concentration. The residue was purified by column chromatography (silica gel cartridge, hexane:ethyl acetate=9:1), so as to obtain the title compound (1.09 g) in the form of a yellow oily substance.

Provenance & Evidence