反应详情

To a solution of (2S)-2-[(tert-butoxycarbonyl)amino]-3-(2-pyridyl)propanoic acid (55.0 g), glycine benzyl ester tosylate (69.7 g), and diphenylphosphoryl azide (46.7 ml) in N,N-dimethylformamide (550 ml) was added dropwise N,N-diisopropylethylamine (75.6 ml) at 4° C. The mixture was warmed to room temperature and stirred for 3 hours. The resulting mixture was poured into ice-cold saturated aqueous sodium hydrogencarbonate solution (700 ml). The mixture was extracted twice with ethyl acetate (total 1.3 L) and washed successively with water (400 ml×2), saturated aqueous ammonium chloride solution (200 ml), aqueous sodium hydrogencarbonate solution (300 ml×2), and brine (40 ml). The organic layer was dried over anhydrous magnesium sulfate and concentrated to give the title compound (77.4 g) as pale brown crystals.

1. extractionThe mixture was extracted twice with ethyl acetate (total 1.3 L)
2. washwashed successively with water (400 ml×2), saturated aqueous ammonium chloride solution (200 ml), aqueous sodium hydrogencarbonate solution (300 ml×2), and brine (40 ml)
3. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
4. concentrationconcentrated