反応 #426970

反応方程式

potassium carbonate

bromomethylbenzene

tert-butyl 2-(4-hydroxyphenyl)ethylcarbamate

→

[2-(4-benzyloxyphenyl)-ethyl]-carbamic acid tert-butyl ester

収率 87.3%

溶媒

acetone

反応条件

後処理

1. 1
   温度The reaction mixture was heated
2. 2
   温度at reflux for 15 hours (h)
3. 3
   濃縮concentrated in vacuo
4. 4
   その他The residue was partitioned between diethyl ether (Et2O) and water (H2O)
5. 5
   洗浄the organic fraction was washed with brine
6. 6
   乾燥dried over sodium sulfate (Na2SO4), suction
7. 7
   ろ過filtered
8. 8
   濃縮concentrated in vacuo
9. 9
   その他The residue was purified by silica gel (SiO2) flash chromatography with 25% Et2O in hexane

実験手順

To a suspension of potassium carbonate (K2CO3; 1.4 grams (g), 10.11 millimole (mmol)) in acetone (40 milliliters (mL)) was added bromomethylbenzene (1.73 g, 10.11 mmol) and tert-butyl 2-(4-hydroxyphenyl)ethylcarbamate (2 g, 8.4 mmol). The reaction mixture was heated at reflux for 15 hours (h) and then concentrated in vacuo. The residue was partitioned between diethyl ether (Et2O) and water (H2O), and the organic fraction was washed with brine, dried over sodium sulfate (Na2SO4), suction filtered, and concentrated in vacuo. The residue was purified by silica gel (SiO2) flash chromatography with 25% Et2O in hexane to afford [2-(4-benzyloxyphenyl)-ethyl]-carbamic acid tert-butyl ester as a white solid (2.4 g). This was dissolved in CH2Cl2 (50 mL) and trifluoroacetic acid (5 mL) was added. After stirring 16 h, the solvent was removed in vacuo, and the residue was redissolved in CH2Cl2, washed with 1M sodium hydroxide (NaOH), dried (Na2SO4) and filtered. The solvent was removed in vacuo to yield 2-(4-benzyloxyphenyl)-ethylamine (1.5 g). This was used without purification in the next step.

出典