反应详情

To a solution of 4-nitrophenylalanine, ethylester, hydrochloride (2.3 g) in dichloromethane (10 ml), add triethylamine (2.55 ml) and then t-butyl 2(R)-(trifluoromethanesulfonyloxy)propionate (2.80 g) (see Preparation 4) in dichloromethane (10 ml). Stir the resulting solution at room temperature for 20 hours. Concentrate the reaction mixture, add diethyl ether and extract with salt solution. Dry over magnesium sulfate and concentrate the ether solution in vacuo to give an oil. Place the oil on a column of silica gel (100 ml, 60-200 mesh) and elute with diethyl ether:hexane 60:40 to give N-[1(S)-ethoxycarbonyl)-2-(4-nitrophenyl)ethyl]-(S)-alanine, t-butyl ester.

1. concentrationConcentrate the reaction mixture
2. additionadd diethyl ether
3. extractionextract with salt solution
4. dry with materialDry over magnesium sulfate
5. concentrationconcentrate the ether solution in vacuo
6. customto give an oil
7. washelute with diethyl ether:hexane 60:40