Реакция #1095109

Уравнение реакции

ethyl acetate

2-(2-benzo[b]thiophen-5-ylethoxy)-acetic acid

sodium boron hydride

hydrochloric acid

→

2-(2-benzo[b]thiophen-5-ylethoxy)-1-ethanol

Выход 92.1%

Растворители

water

tetrahydrofuran

Условия реакции

Обработка

1. 1
   workup.ADDITIONis added to the solution
2. 2
   workup.ADDITIONis added to the reaction mixture over a period of 20 minutes
3. 3
   workup.STIRRINGthe resulting mixture is stirred at the same temperature as above for 30 minutes
4. 4
   workup.WAITat ambient temperature for 2 hours
5. 5
   Другоеthe organic layer is separated
6. 6
   ПромывкаThe organic layer is washed with water and saturated aqueous solution of sodium chloride successively
7. 7
   Сушкаdried over anhydrous magnesium sulfate
8. 8
   workup.DISTILLATIONthe solvent is distilled off under reduced pressure
9. 9
   Другоеthe residue is purified by column chromatography (eluent: n-hexane:ethyl acetate=3:1 to 2:1)

Методика

In 27 mL of tetrahydrofuran is dissolved 2.70 g of 2-(2-benzo[b]thiophen-5-ylethoxy)-acetic acid. At an ice-cooled temperature, 0.65 g of sodium boron hydride is added to the solution, and stirred at the same temperature as above for 10 minutes. Then, at an ice-cooled temperature, 3.24 g of boron trifluoride diethyl ether complex is added to the reaction mixture over a period of 20 minutes, and the resulting mixture is stirred at the same temperature as above for 30 minutes and then at ambient temperature for 2 hours. The reaction mixture is introduced into a mixture of ethyl acetate and water, pH is adjusted to 1.0 with 2 mol/L hydrochloric acid, and the organic layer is separated. The organic layer is washed with water and saturated aqueous solution of sodium chloride successively and dried over anhydrous magnesium sulfate, the solvent is distilled off under reduced pressure, and the residue is purified by column chromatography (eluent: n-hexane:ethyl acetate=3:1 to 2:1) to obtain 2.34 g of 2-(2-benzo[b]thiophen-5-ylethoxy)-1-ethanol as an oily product.

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