反应详情

24.8 g of 3-(2-thienyl)alanine (144.8 mmol) were added in portions to 11.0 g of LiAlH4 in 550 ml of tetrahydrofuran, heated to reflux. The mixture was then heated under reflux for 8 hours and subsequently stirred at room temperature overnight. 17.6 ml of 10% NaOH solution were added and then 22 ml of H2O were slowly added dropwise, and the mixture was stirred for 5 minutes. Then, first 391 ml of 10% NaOH solution and subsequently, at −5° C., 22.2 g of benzyl chloroformate (130.32 mmol) were added, and the mixture was stirred at room temperature for 3 hours. For workup, the mixture was extracted with dichloromethane, the organic phase was dried, the solvent was evaporated and the remaining residue was filtered through silica gel (eluent: CH2Cl2/methanol 2.5%). 36.8 g of the title compound were obtained as a yellowish oil.

1. temperatureheated to reflux
2. temperatureThe mixture was then heated
3. temperatureunder reflux for 8 hours
4. stirringthe mixture was stirred for 5 minutes
5. stirringthe mixture was stirred at room temperature for 3 hours
6. extractionFor workup, the mixture was extracted with dichloromethane
7. customthe organic phase was dried
8. customthe solvent was evaporated
9. filtrationthe remaining residue was filtered through silica gel (eluent: CH2Cl2/methanol 2.5%)