反应详情

A solution of sodium hydride (934 mg, 23.4 mmol) in tetrahydrofuran (50 mL) was treated with ethyl 3-methylpyrazole-5-carboxylate (3.00 g, 19.5 mmol) and the reaction mixture stirred at room temperature for 30 minutes. 2-(2-Bromoethoxy)tetrahydro-2H-pyran (3.5 mL, 19.5 mmol) and lithium iodide (50 mg, 0.39 mmol) were added and the reaction mixture refluxed for 16 hours. The reaction mixture was cooled and taken up in ethyl acetate and water. The organics were separated and washed with 10% citric acid solution, water, saturated sodium hydrogencarbonate solution and brine, dried over magnesium sulphate and concentrated in vacuo. The residue was purified by column chromatography on silica gel eluting with dichloromethane:methanol 99:1 to 95:5 to yield the title product, 4.47 g.

1. temperaturethe reaction mixture refluxed for 16 hours
2. temperatureThe reaction mixture was cooled
3. customThe organics were separated
4. washwashed with 10% citric acid solution, water, saturated sodium hydrogencarbonate solution and brine
5. dry with materialdried over magnesium sulphate
6. concentrationconcentrated in vacuo
7. customThe residue was purified by column chromatography on silica gel eluting with dichloromethane:methanol 99:1 to 95:5