反应详情

To a stirred solution 3-amino-2-(3,4-dimethoxy-phenyl)-propionic acid ethyl ester hydrochloride (6.5 g, 25.8 mmol) and (3-sec-butoxy-phenyl)-acetic acid (5.9 g, 28.4 mmol) in N,N-dimethylformamide (130 mL) was added O-benzotriazole-N,N,N′,N′-tetramethyl-uronium hexaflurophosphate (HBTU) (11.8 g, 31.1 mmol) and diisopropylethylamine (14.8 mL, 85.0 mmol). The reaction mixture was stirred at room temperature for 15 hrs. The solvent was evaporated and the residue was diluted with ethyl acetate and saturated sodium bicarbonate solution. The aqueous phase was extracted with ethyl acetate (3×100 mL). The combined extracts were washed with 1N hydrogen chloride solution (50 mL), water (50 mL), saturated aqueous sodium chloride solution (50 mL), dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 70–230 mesh, 40% ethyl acetate/hexane, 100% ethyl acetate) afforded 3-[2-(3-sec-butoxy-phenyl)-acetylamino]-2-(3,4-dimethoxy-phenyl)-propionic acid ethyl ester (11.2 g, 98% yield) as a red oil.

1. customThe solvent was evaporated
2. additionthe residue was diluted with ethyl acetate and saturated sodium bicarbonate solution
3. extractionThe aqueous phase was extracted with ethyl acetate (3×100 mL)
4. washThe combined extracts were washed with 1N hydrogen chloride solution (50 mL), water (50 mL), saturated aqueous sodium chloride solution (50 mL)
5. dry with materialdried over anhydrous magnesium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo