反应详情

10 g of tert-butanol, 10.1 g of BOC-anhydride and 12.27 g of diisopropylethylamine dissolved in 30 ml of tetrahydrofuran are added at 0° to a suspension of 12.12 g of D-tryptophan methyl ester hydrochloride in 80 ml of abs. tetrahydrofuran. After being stirred for two hours at room temperature, the reaction mixture is poured into ice/470 ml of 0.3N HCl and extracted three times with ethyl acetate. The combined organic phases are washed once with water and twice with sat. NaCl solution, dried (MgSO4) and concentrated by evaporation. The residue is made into a slurry in diethyl ether/petroleum ether and filtered with suction. The title compound is thus obtained in the form of colourless crystals having a melting point of 148-1490. Rf (methylene chloride)=0.24.

1. extractionextracted three times with ethyl acetate
2. washThe combined organic phases are washed once with water and twice with sat. NaCl solution
3. dry with materialdried (MgSO4)
4. concentrationconcentrated by evaporation
5. filtrationfiltered with suction