Methyl iodide → ethyl 1-(4-ethoxy-2,6-difluorobenzyl)-5-methoxy-4-methyl-1H-pyrazole-3-carboxylate

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Reaction Steps

3.95 g of ethyl 1-(4-ethoxy-2,6-difluorobenzyl)-5-hydroxy-4-methyl-1H-pyrazole-3-carboxylate 1-1-1 (11.6 mmol, 1.0 eq.) were dissolved in 50 mL of acetone. 1.45 mL of iodomethane (23.2 mmol, 2.0 eq.) and 5.78 g (41.8 mmol, 3.6 eq.) of potassium carbonate were added and stirred over for 24 hours at rt. 1.45 mL of iodomethane (23.2 mmol, 2.0 eq.) were added and the mixture was stirred for further 24 hours at rt. The suspension was filtered off over sea sand and the filtrate was concentrated in vacuo. The residue was extracted by DCM and water. The aqueous layer was extracted twice with DCM. The combined organic layers were dried over sodium sulfate and concentrated in vacuo. The residue was purified by flash chromatography to give 2.29 g (6.46 mmol, 55.7%) of analytically pure target compound.

Provenance & Evidence