Реакция #669936

Уравнение реакции

sodium cyclopentadienylide

1-bromo-2-fluoroethane

sodium hydroxide

hydrogen peroxide

2-methyl-2-butene

→

(RS)-3-(2-fluoroethyl)-3-cyclopenten-1-ol

Выход 16.0%

Растворители

tetrahydrofuran

Условия реакции

Обработка

1. 1
   Температураcooling and under nitrogen
2. 2
   ДругоеThe resulting reaction liquid
3. 3
   Фильтрацияwas filtered with cerite, and the filtrate
4. 4
   workup.ADDITIONwas added under ice-
5. 5
   Температураcooling and under nitrogen stream to a tetrahydrofuran solution of disiamylborane
6. 6
   Другоеprepared
7. 7
   workup.STIRRINGthe resulting mixture was stirred for 8 hours
8. 8
   Температураcooling to the reaction liquid
9. 9
   Другоеobtained above, and the resulting mixture
10. 10
    workup.STIRRINGwas stirred for 1 hour
11. 11
    ДругоеThe reaction liquid
12. 12
    Другоеthus obtained
13. 13
    Экстракцияwas extracted two times with diethyl ether
14. 14
    ПромывкаThe combined ether layer was washed with saturated aqueous sodium chloride solution
15. 15
    Сушкаdried over anhydrous magnesium sulfate
16. 16
    workup.DISTILLATIONthe solvent was distilled off under reduced pressure
17. 17
    ДругоеThe residue obtained

Методика

To 25 ml of 2 M tetrahydrofuran solution of sodium cyclopentadienylide was added under ice-cooling and under nitrogen stream 6.3 g of 1-bromo-2-fluoroethane and stirred for 2 hours. The resulting reaction liquid was filtered with cerite, and the filtrate was added under ice-cooling and under nitrogen stream to a tetrahydrofuran solution of disiamylborane prepared by using 75 ml of 1 M borane-tetrahydrofuran complex and 18.5 ml of 2-methyl-2-butene and the resulting mixture was stirred for 8 hours. Then 3 N aqueous sodium hydroxide solution and 30% aqueous hydrogen peroxide were successively added under ice-cooling to the reaction liquid obtained above, and the resulting mixture was stirred for 1 hour. The reaction liquid thus obtained was extracted two times with diethyl ether. The combined ether layer was washed with saturated aqueous sodium chloride solution, then dried over anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure. The residue obtained was subjected to silica gel column chromatography to obtain 1.1 g of (RS)-3-(2-fluoroethyl)-3-cyclopenten-1-ol. Yield 16%

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