Iodine → 3-(2,5-dimethylpyrrol-1-yl)-1-(2-fluorophenyl)-5-iodo-1H-pyrazole

Participants

Reaction Steps

Under nitrogen atmosphere, a solution of 3-(2,5-dimethylpyrrol-1-yl)-1-(2-fluorophenyl)-1H-pyrazole (1.19 g) in tetrahydrofuran (10 ml) was cooled to −78° C., n-butyllithium (3.5 ml, 1.6M solution in n-hexane) was added dropwise thereto, and the mixture was stirred for 30 minutes. To this reaction solution was added dropwise a solution of iodine (1.42 g) in tetrahydrofuran (5 ml), and the mixture was stirred for 30 minutes. To this reaction mixture was added a saturated aqueous solution of sodium sulfite and a saturated aqueous solution of ammonium chloride, and the mixture was extracted with ethyl acetate. This organic layer was washed with a saturated aqueous solution of sodium chloride, dried over anhydrous sodium sulfate, and then concentrated under reduced pressure. To the resulting residue was added a mixed solvent of n-hexane/ethyl acetate (=6/1), the mixture was stirred. A solid was collected from this suspension by filtration, and was dried under reduced pressure to give the titled compound (1.23 g).

Provenance & Evidence