反应详情

温度

0 °C

To a solution of N-(2-acetylthiomethyl-4-phenylbutanoyl)-(L)-leucine (derived from the higher RfTLC fraction) (182 mg. 0.5 mmole) in 2 mL of THF at 0° C. was added aniline (93 mg, 1.0 mmole) and 1-hydroxybenzotriazole hydrate (HOBT·H2O, 101 mg, 0.75 mole) and N-methylmorpholine (202 mg, 2.0 mmole). The mixture was stirred at 0° C. for 15 minutes, then 192 mg of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (EDC·HCl, 1.0 mmole) was added and the mixture stirred overnight. The solution was worked up by adding 7 mL methylene chloride and the mixture extracted with 3×3 ml of 5% sodium bicarbonate, then 2×2 mL of brine. The organic layer was dried over MgSO4, filtered and the solvent removed under reduced pressure. The residue was purified by flash column chromatography on silica gel eluted with methylene chloride/ethyl acetate (90/10) to obtain 110 mg of product (yield =50%). By 1H-NMR, we see two rotomers present at room temperature.

1. customat 0° C.
2. stirringthe mixture stirred overnight
3. extractionthe mixture extracted with 3×3 ml of 5% sodium bicarbonate
4. dry with materialThe organic layer was dried over MgSO4
5. filtrationfiltered
6. customthe solvent removed under reduced pressure
7. customThe residue was purified by flash column chromatography on silica gel
8. washeluted with methylene chloride/ethyl acetate (90/10)