Triethylamine → 5-(Ethylthio)carbonyloxy-1-methylpyrazol-4-yl 3-(methoxy)-2-methyl-4-(methylsulfonyl)phenyl ketone

Participants

Reaction Steps

To a solution of 5-hydroxy-1-methylpyrazol-4-yl 3-methoxy-2-methyl-4-(methylsulfonyl)phenyl ketone (100 mg, 0.3 mmol) in dry tetrahydrofuran (5 mL) were added triethylamine (61 mg) and 96% S-ethyl chlorothiolformate (50 mg) at room temperature. After the reaction solution was stirred for 1 hour, 150 mL of ethyl acetate was added. The mixture was washed twice with a saturated brine, the organic layer was dried over anhydrous sodium sulfate, and the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (n-hexane:ethyl acetate=2:1) to obtain the desired product as an oil.

Provenance & Evidence