反応 #1095109

反応方程式

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

収率 92.1%

溶媒

water

tetrahydrofuran

反応条件

後処理

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
   その他the organic layer is separated
6. 6
   洗浄The organic layer is washed with water and saturated aqueous solution of sodium chloride successively
7. 7
   乾燥dried over anhydrous magnesium sulfate
8. 8
   workup.DISTILLATIONthe solvent is distilled off under reduced pressure
9. 9
   その他the residue is purified by column chromatography (eluent: n-hexane:ethyl acetate=3:1 to 2:1)

実験手順

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.

出典