反应详情

6.3 g (0.03 mol) of cis-1-(2-fluorobenzyloxy)-cyclopentan-2-ol (Example 2) in 100 ml of absolute dioxan were added dropwise to a suspension of 0.72 g (0.03 mol) of sodium hydride (0.9 g of 80% pure sodium hydride in toluene) in 100 ml of absolute dioxan at 5° C. under nitrogen. After stirring the mixture at room temperature for 30 minutes, it was warmed to 70° C. for 45 minutes and cooled, 1.26 g (0.03 mol) of methyl iodide in dioxan were added dropwise and the mixture was then heated to the boil for 4 hours. After cooling the mixture to room temperature, 5 ml of methanol were added dropwise and the suspension was concentrated on a rotary evaporator. The residue was taken up in water and the mixture was extracted again with methylene chloride. The combined methylene chloride phases were dried over sodium sulphate and filtered and the solvent was stripped off from the filtrate on a rotary evaporator. The oily residue was distilled. 5 g (75% of theory) of cis-1-(2-fluorobenzyloxy)-2-methoxy-cyclopentane of boiling point 90° C./0.1 mm Hg were obtained.

1. temperatureit was warmed to 70° C. for 45 minutes
2. temperaturecooled
3. temperaturethe mixture was then heated to the boil for 4 hours
4. temperatureAfter cooling the mixture to room temperature
5. concentrationthe suspension was concentrated on a rotary evaporator
6. extractionthe mixture was extracted again with methylene chloride
7. dry with materialThe combined methylene chloride phases were dried over sodium sulphate
8. filtrationfiltered
9. customthe solvent was stripped off from the filtrate on a rotary evaporator
10. distillationThe oily residue was distilled