反应详情

To a mixture of O-methyl-L-threonine (3.0 g, 22.55 mmol), NaOH (0.902 g, 22.55 mmol) in H2O (15 mL) was added ClCO2Me (1.74 mL, 22.55 mmol) dropwise at 0° C. The mixture was allowed to stir for 12 h and acidified to pH 1 using 1N HCl. The aqueous phase was extracted with EtOAc and (2×250 mL) and 10% MeOH in CH2Cl2 (250 mL) and the combined organic phases were concentrated under in vacuo to afford a colorless oil (4.18 g, 97%) which was of sufficient purity for use in subsequent steps. 1H NMR (400 MHz, CDCl3) δ 4.19 (s, 1H), 3.92-3.97 (m, 1H), 3.66 (s, 3H), 1.17 (d, J=7.7 Hz, 3H). LCMS: Anal. Calcd. for C7H13NO5: 191; found: 190 (M−H)−.

1. extractionThe aqueous phase was extracted with EtOAc and (2×250 mL) and 10% MeOH in CH2Cl2 (250 mL)
2. concentrationthe combined organic phases were concentrated under in vacuo