反应详情

N-(t-butoxycarbonyl)-3-phenoxy-DL-phenylalanine (4.40 g) was dissolved in dry tetrahydrofuran (100 ml) and triethylamine (1.80 ml) was added under ice-cooling, followed by stirring for 15 minutes. To this solution was added ethyl chlorocarbonate (1.44 g) and the mixture was stirred for 30 minutes. After adding 4-amino-2-chloropyridine (1.54 g), the reaction was carried out at room temperature for 10 hours. Thereafter, the solid was filtered off and the filtrate was concentrated under a reduced pressure. The residue was extracted with ethyl acetate. The extract was purified with a column chromatography (hexane/ethyl acetate=3/1) to obtain N-(t-butoxycarbonyl)-3-phenoxy-DL-phenylalanine 4-(2-chloro)pyridylamide (I) (0.60 g), which was confirmed by the following NMR analysis, in the form of a white powder.

1. temperaturecooling
2. stirringthe mixture was stirred for 30 minutes
3. waitthe reaction was carried out at room temperature for 10 hours
4. filtrationThereafter, the solid was filtered off
5. concentrationthe filtrate was concentrated under a reduced pressure
6. extractionThe residue was extracted with ethyl acetate
7. customThe extract was purified with a column chromatography (hexane/ethyl acetate=3/1)