反应详情

To a tetrahydrofuran (262 mL) solution of ethyl 3,5-dibromo-1H-pyrazole-4-carboxylate (20.93 g, 703 mmol) was added N,N-diisopropylethylamine (24.5 mL, 141 mmol), and chloromethyl methyl ether (6.42 mL, 84.3 mmol) was added dropwise while cooling on ice, and stirred at room temperature for one hour. After the reaction was completed, water was added while cooling on ice, the reaction mixture was extracted with ethyl acetate, the organic layer was dried over magnesium sulfate, and then the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (n-heptane/ethyl acetate=3/1) to obtain the title compound (23.4 g, 68.5 mmol).

1. additionwas added dropwise
2. temperaturewhile cooling on ice
3. temperaturewhile cooling on ice
4. extractionthe reaction mixture was extracted with ethyl acetate
5. dry with materialthe organic layer was dried over magnesium sulfate
6. distillationthe solvent was distilled off under reduced pressure
7. customThe residue was purified by silica gel column chromatography (n-heptane/ethyl acetate=3/1)