反应详情

N-(tert-butoxycarbonyl)glycine (22.4 g, 128 mmol), ethyl 2-amino-3-oxobutanoate (21.1 g, 116 mmol), ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (28.9 g, 151 mmol), 1-hydroxybenzotriazole (23.1 g, 151 mmol), triethylamine (16.2 mL, 116 mmol), in chloroform (350 mL) was stirred for 13 h at room temperature, and then triethylamine (20.0 mL, 143 mmol) was added. After being stirred for 4 h at same temperature, the reaction mixture was poured into saturated aqueous sodium bicarbonate. The organic layer was separated and the aqueous layer was extracted with chloroform. The organic layer was combined, washed with saturated brine, dried over sodium sulfate, filtrated and concentrated in vacuo. The crude was purified by silica gel column chromatography (hexane:ethyl acetate=2:1 to 1:1) to give ethyl 2-{[N-(tert-butoxycarbonyl)glycyl]amino}-3-oxobutanoate. MS (APCI): m/z 320 (M+NH4), 303 (M+H).

1. customThe organic layer was separated
2. extractionthe aqueous layer was extracted with chloroform
3. washwashed with saturated brine
4. dry with materialdried over sodium sulfate
5. filtrationfiltrated
6. concentrationconcentrated in vacuo
7. customThe crude was purified by silica gel column chromatography (hexane:ethyl acetate=2:1 to 1:1)