反应详情

The title compound was prepared by dissolving 9.27 g (0.0348 mols) of the N-(3-nitrophenylacetyl)-L-alanine methyl ester in 60 mL of dioxane and 15 mL of H2O and adding LiOH (3.06 g, 0.0731 mol) that has been dissolved in 15 mL of H2O. After stirring for 4 hours, the dioxane was removed under reduced pressure and the residue diluted with EtOAc, the layers were separated and the aqueous layer acidified to pH 2. The aqueous layer was back extracted with EtOAc (4×100 ml), the combined organics were dried over Na2SO4 and the solvent was removed under reduced pressure after filtration. The residue was recrystallized from EtOAc/isooctane giving 7.5 g (85%). C11H12N2O5 requires C, 52.38 H, 4.80 N, 11.11. Anal found C, 52.54 H, 4.85 N, 11.08. [α]23=−29.9 @ 589 nm.

1. customthe dioxane was removed under reduced pressure
2. additionthe residue diluted with EtOAc
3. customthe layers were separated
4. extractionThe aqueous layer was back extracted with EtOAc (4×100 ml)
5. dry with materialthe combined organics were dried over Na2SO4
6. customthe solvent was removed under reduced pressure
7. filtrationafter filtration
8. customThe residue was recrystallized from EtOAc/isooctane giving 7.5 g (85%)