反应详情

温度

-70 °C

3.0 g (12.0 mmol) of 2-(4-propylphenyl)selenophene are initially introduced in 30 ml of diethyl ether, and 9.4 ml (15.0 mmol, 15% soln. in hexane) of n-BuLi are metered in rapidly. The mixture is heated under reflux for 30 min and subsequently cooled to −70° C. 3.0 ml (48.2 mol) of methyl iodide are added in one portion, and the mixture is warmed to RT and stirred for 3 h. Sat. ammonium chloride soln. and conc. ammonia soln. are added, and the batch is stirred vigorously for a few minutes. The organic phase is separated off, and the aqueous phase is extracted with MTBE. The combined organic phases are washed with 2 N hydrochloric acid and sat. sodium chloride soln. and dried using sodium sulfate. The solution is concentrated to dryness, and the residue is purified by column chromatography (SiO2, n-heptane:EtOAc=20:1→10:1→5:1). The further purification is carried out by flash chromatography (SiO2 RP-18, ACN:water=9:1); 2-methyl-5-(4-propylphenyl)selenophene is obtained as a colourless solid (m.p. 31° C.).

1. temperatureThe mixture is heated
2. temperatureunder reflux for 30 min
3. temperaturethe mixture is warmed to RT
4. additionare added
5. stirringthe batch is stirred vigorously for a few minutes
6. customThe organic phase is separated off
7. extractionthe aqueous phase is extracted with MTBE
8. washThe combined organic phases are washed with 2 N hydrochloric acid and sat. sodium chloride soln
9. customand dried
10. concentrationThe solution is concentrated to dryness
11. customthe residue is purified by column chromatography (SiO2, n-heptane:EtOAc=20:1→10:1→5:1)
12. customThe further purification