反应详情

Dissolve 50 g (0.2 mole) of 2-(4-difluoromethoxyphenyl)-3-methylbutyric acid in 150 g of ethyl alcohol and to this solution is added 0.2 mol of resolving agent 1-(4-nitrophenyl)-2-dimethylamino-1,3-propanediol. Heat the solution with stirring under reflux for 8 hours, then cool, filter, and transfer the resulting solids to 73 g of 10% hydrochloric acid. Heat the mixture with stirring at 30° C. for 2 hours and then allow the mixture to cool to room temperature. The resulting mixture is extracted with benzene 2-3 times, and the solvent benzene is then removed by distillation to give 21 g (yield: 42%) of (S)-2-(4-difluoromethoxyphenyl)-3-methylbutyric acid.

1. additionto this solution is added 0.2 mol
2. temperatureHeat the solution
3. temperatureunder reflux for 8 hours
4. temperaturecool
5. filtrationfilter
6. temperatureHeat the mixture
7. stirringwith stirring at 30° C. for 2 hours
8. extractionThe resulting mixture is extracted with benzene 2-3 times
9. customthe solvent benzene is then removed by distillation