反应详情

N-(1-Ethoxycarbonyl-3-Phenylpropyl)-L-Alanine Benzylester (4.2 g) is dissolved in 40 ml ethanol, to which is added 630 mg 10% Pd-C and a few drops of acetic acid. Hydrogenation occurs under a 30 psi hydrogen atmosphere at room temperature overnight. The resulting mixture is filtered through celite and dried under vacuum to remove the solvent, yielding a residue. The residue is partitioned between chloroform and aqueous 5% NaHCO3, separated, and the chloroform layer further washed with aqueous 5% NaHCO3. The aqueous layers are combined, acidified to pH 3.5 with dilute HCl, extracted with chloroform or ethylacetate several times, dried over MgSO4, and placed under vacuum to evaporate the solvent and yield 2.5 g of the diastereoisomeric product, a brown sticky solid [TLC (Silica gel; CHCl3 /MeOH/HOAC=9:1:0.5); Rf=0.4].

1. filtrationThe resulting mixture is filtered through celite
2. customdried under vacuum
3. customto remove the solvent
4. customyielding a residue
5. customThe residue is partitioned between chloroform and aqueous 5% NaHCO3
6. customseparated
7. washthe chloroform layer further washed with aqueous 5% NaHCO3
8. extractionextracted with chloroform or ethylacetate several times
9. dry with materialdried over MgSO4
10. customto evaporate the solvent and yield 2.5 g of the diastereoisomeric product