反应详情

Pent-4-enoyl chloride (0.915 ml, 8.25 mmol) was added to a solution of (R)-2-amino-3-(tritylthio)propanoic acid (1.50 g, 4.13 mmol) and sodium carbonate (1.31 g, 12.4 mmol) in tetrahydrofuran (3.5 ml) and water (7 ml), and the mixture was stirred at room temperature for one hour. The reaction mixture was then adjusted to pH 2 by adding concentrated hydrochloric acid thereto at 0° C. After dilution with ethyl acetate, salting-out extraction was carried out by adding an appropriate amount of NaCl. The resulting organic extract was washed with brine, dried over magnesium sulfate and then concentrated under reduced pressure. The resulting residue was purified by reverse-phase silica gel column chromatography (10 mM aqueous ammonium acetate solution/methanol=70/30→0/100) to afford (R)-2-(pent-4-enamido)-3-(tritylthio)propanoic acid (Compound 2h) (1.14 g, 62%).

1. customat 0° C
2. extractionAfter dilution with ethyl acetate, salting-out extraction
3. additionby adding an appropriate amount of NaCl
4. extractionThe resulting organic extract
5. washwas washed with brine
6. dry with materialdried over magnesium sulfate
7. concentrationconcentrated under reduced pressure
8. customThe resulting residue was purified by reverse-phase silica gel column chromatography (10 mM aqueous ammonium acetate solution/methanol=70/30→0/100)