反应详情

温度

0 °C

420 mg (0.002 mol) of 4-(methoxycarbonylmethyloxy)benzoic acid, 270 mg (0.002 mol) of 1-hydroxybenzotriazole and 588 mg (0.002 mol) of tert-butyl (2S)-3-amino-2-benzyloxycarbonylaminopropionate were dissolved in 5 ml of dimethylformamide. The solution was cooled to 0° C. and treated with 453 mg (0.0022 mol) of N,N′-dicyclohexylcarbodiimide and then stirred at 0° C. for 10 min and at room temperature for 2 h. For working-up, the urea was filtered off and the filtrate was concentrated to dryness. The pure compound was obtained by chromatography of the crude product on silica gel (dichloromethane/acetonitrile 20/1). Yield: 820 mg.

1. filtrationthe urea was filtered off
2. concentrationthe filtrate was concentrated to dryness