反应详情

温度

0 °C

ε-(2-chlorobenzyloxycarbonyl)-lysine allyl ester (from example 18) was dissolved in methanol (50 mL) and cooled to 0° C. To the resulting solution was added sodium cyanoborohydride (5.9 mmol) followed by acetic acid (0.75 mL). After 5 minutes BOC-amino-acetaldehyde (13.3 mmol) was added and the reaction mixture was stirred for an additional 1 h. The methanol was removed in vacuo and the oil was dissolved in ethyl acetate (40 mL), washed with saturated aqueous NaHCO3, brine, dried over Na2SO4 and concentrated to give a clear colorless oil. This oil was dissolved in dry ether (80 mL), cooled to −20° C., and a molar equivalent of HCl in ether was added slowly. The resulting white solid was collected by filtration and air dried. Precipitation of the air-dried white solid from dry ether gave analytically pure title compound.

1. customThe methanol was removed in vacuo
2. dissolutionthe oil was dissolved in ethyl acetate (40 mL)
3. washwashed with saturated aqueous NaHCO3, brine
4. dry with materialdried over Na2SO4
5. concentrationconcentrated
6. customto give a clear colorless oil
7. temperaturecooled to −20° C.
8. filtrationThe resulting white solid was collected by filtration and air
9. customdried
10. customPrecipitation of the air-dried white solid from dry ether