反应详情

A mixture of 4-ethyl 1-tert-butyl 3-hydroxy-1H-pyrazole-1,4-dicarboxylate (30.75 g), chloromethyl methyl ether (4.56 mL), N,N-diisopropylethylamine (11.9 mL) and tetrahydrofuran (150 mL) was stirred at room temperature for 2 hrs. The reaction mixture was poured into saturated aqueous sodium hydrogen carbonate, and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated. The residue was subjected to silica gel column chromatography and eluted with ethyl acetate-hexane (1:9-1:2, v/v) to give 4-ethyl 1-tert-butyl 3-(methoxymethoxy)-1H-pyrazole-1,4-dicarboxylate as a pale-yellow oil (3.52 g, yield 20%).

1. extractionthe mixture was extracted with ethyl acetate
2. washThe organic layer was washed with saturated brine
3. dry with materialdried over anhydrous magnesium sulfate
4. concentrationconcentrated
5. washeluted with ethyl acetate-hexane (1:9-1:2