反应详情

A 100 mL, round bottom flask equipped with a magnetic stirrer and a nitrogen inlet is added N-benzyloxycarbonyl-L-valine (3.6 g), dichloromethane (25 mL), and 2,2-dimethoxyethanol (1.85 g) and the mixture is cooled using an ice bath (0-5° C.). DMAP (0.089 g) is added to the reaction mixture followed by the addition of DCC (3.6 g) over a period of 2 minutes. The suspended solid is filtered, the filter cake is washed with 3×10 mL of heptanes, and the filtrate is concentrated. The crude product is purified by silica gel chromatography (4:1, heptanes/ethyl acetate eluent) to provide 5.3 g of 2,2-dimethoxyethyl N-benzyloxycarbonyl-L-valinate.

1. customA 100 mL, round bottom flask equipped with a magnetic stirrer and a nitrogen inlet
2. temperaturethe mixture is cooled
3. custom(0-5° C.)
4. filtrationThe suspended solid is filtered
5. washthe filter cake is washed with 3×10 mL of heptanes
6. concentrationthe filtrate is concentrated
7. customThe crude product is purified by silica gel chromatography (4:1, heptanes/ethyl acetate eluent)