反应详情

Ethyl 2-amino-3-(3,4-dimethoxyphenyl)propionate (the compound obtained in Example 1-(1)) (15.2 g), 4-isopropyloxybenzoic acid (10.8 g), and 1-hydroxybenzotriazole monohydrate (9.2 g) are dissolved in methylene chloride (120 ml), and thereto is added 1,3-dicyclohexylcarbodiimide (12.4 g) under ice-cooling, and the mixture is stirred at room temperature overnight. The insoluble materials are removed by filtration, and the filtrate is washed with a saturated aqueous sodium hydrogen carbonate solution and a saturated brine, dried over magnesium sulfate, and concentrated under reduced pressure. The precipitated crystals are collected by filtration with diethyl ether to give ethyl 3-(3,4-dimethoxyphenyl)-2-{[4-(isopropyloxy)-phenyl]carbonylamino}propionate (24.2 g).

1. temperaturecooling
2. customThe insoluble materials are removed by filtration
3. washthe filtrate is washed with a saturated aqueous sodium hydrogen carbonate solution
4. dry with materiala saturated brine, dried over magnesium sulfate
5. concentrationconcentrated under reduced pressure
6. filtrationThe precipitated crystals are collected by filtration with diethyl ether