反应详情

5 gm of 2-(benzoylamino)-3-(imidazol-4-yl)propanoic acid in 100 ml of benzene, 5 ml of propargyl alcohol, and 5.22 gm of p-toluenesulfonic acid.H2O was heated at reflux with the azeotropic removal of water by means of a Dean-Stark apparatus. After approximately 2 days of refluxing and the stoichiometric amount of water was produced, the reaction mixture was cooled, and a precipitate, the p-toluenesulfonic acid salt of the title compound was filtered out. The salt was taken up in water, the pH adjusted to 7.5 with 1.0N NaOH in a two phase system of water-dichloromethane. The layers were separated and the aqueous portion extracted 3×30 ml of CH2Cl2. The organic fractions were pooled, dried over anhydrous magnesium sulfate, and concentrated in vacuo to give the title compound.

1. temperatureAfter approximately 2 days of refluxing
2. temperaturethe reaction mixture was cooled
3. filtrationa precipitate, the p-toluenesulfonic acid salt of the title compound was filtered out
4. customThe layers were separated
5. extractionthe aqueous portion extracted 3×30 ml of CH2Cl2
6. dry with materialdried over anhydrous magnesium sulfate
7. concentrationconcentrated in vacuo