反应详情

温度

65 °C

To a solution of 3-(4-hydroxyphenyl)propanoic acid (3.32 g, 20 mmol) in dry DMF (20 ml) is carefully added 1,1′-carbonyldiimidazole (3.24 g, 20 mmol) portionwise. The reaction mixture is stirred at 40° C. for 2 hours after which time DBU (6.02 ml, 40 mmol) and tert-butanol (4.78 ml, 50 mmol) are added and the reaction mixture is now stirred at 65° C. for 2 days. The reaction mixture is allowed to cool to room temperature and poured into water (50 ml) and the product is extracted with diethyl ether (3×30 ml). The organics are combined, dried (MgSO4) and the solvent removed in vacuo to give a yellow oil. Purification by flash chromatography (SiO2, EtOAc/iso-hexane) yields 3-(4-Hydroxy-phenyl)-propionic acid tert-butyl ester as a colourless oil. 1H NMR (DMSO-d6) 9.1 (1H, s), 7.0 (2H, d, J=8.45), 6.65 (2H, d, J=8.45), 2.7 (2H, t, J=7.28), 2.4 (2H, t, J=7.28), 1.4 (9H, s).

1. additionare added
2. temperatureto cool to room temperature
3. extractionthe product is extracted with diethyl ether (3×30 ml)
4. dry with materialdried (MgSO4)
5. customthe solvent removed in vacuo
6. customto give a yellow oil
7. customPurification by flash chromatography (SiO2, EtOAc/iso-hexane)