反应详情

400 mg (10.0 mmol) of sodium hydride (60% suspension in paraffin oil) are washed with n-pentane and suspended in 5 ml of THF. A solution of 1.9 g (about 6.0 mmol) of crude [5-(4-ethoxy-2,3-difluorophenyl)selenophen-2-yl]methanol in 20 ml of THF is added dropwise, and the mixture is stirred for 2 h. 1.0 ml (16.1 mmol) of methyl iodide is metered in, and the batch is stirred at RT for 2 h. Water is carefully added to the reaction mixture, which is then acidified using 2 N hydrochloric acid. The mixture is extracted with MTBE, and the extract is washed with sat. sodium chloride soln. The solution is dried using sodium sulfate and concentrated to dryness. The crude product is purified by column chromatography (SiO2, toluene). The further purification is carried out by recrystallisation from ethanol and MTBE. 2-(4-Ethoxy-2,3-difluorophenyl)-5-methoxymethylselenophene is obtained as a solid having an m.p. of 84° C.

1. stirringis stirred at RT for 2 h
2. extractionThe mixture is extracted with MTBE
3. washthe extract is washed with sat. sodium chloride soln
4. customThe solution is dried
5. concentrationconcentrated to dryness
6. customThe crude product is purified by column chromatography (SiO2, toluene)
7. customThe further purification
8. customis carried out by recrystallisation from ethanol and MTBE