反应详情

To a solution of (S)-2-aminopentanedioic acid (100 g, 680 mmol) in H2O (500 mL) was added HCl (140 mL, 1.6 mol) and then NaNO2 (70.4 g, 1.02 mol) in H2O (100 mL) was added slowly at −5° C.-0° C., and the reaction mixture was stirred at room temperature for 24 hours. The solvent was concentrated in vacuo below 50° C. The residue was suspended in EtOAc (500 mL) and filtered. The filtrate was dried over Na2SO4 and concentrated in vacuo to afford 56 g crude product of (2S)-5-oxotetrahydrofuran-2-carboxylic acid (compound 28a) as yellow oil, which was used in next step without further purification.

1. concentrationThe solvent was concentrated in vacuo below 50° C
2. filtrationfiltered
3. dry with materialThe filtrate was dried over Na2SO4
4. concentrationconcentrated in vacuo