反应详情

温度

90 °C

To a suspension of 1-(4-Chlorophenyl)-1-cyclopropane carboxylic acid (400 mg) in benzene (8 mL) was added triethylamine (0.23 mL) and diphenylphosphoryl azide (0.44 mL) over 5 minutes under argon. The mixture was the allowed to stir at 90° C. for 2 hours. D,L-valine methyl ester hydrochloride was added in one portion and stirring was continued at 90° C. for 20 hours. The mixture was cooled and added to ethyl acetate and 1 M NaOH. The layers were separated and the organic phase was washed with brine, dried over Na2SO4 and evaporated. The residue was purified by flash chromatography using methanol/ethyl acetate 9:1 as an eluent. Fractions containing the desired material were combined and evaporated to give 2-{3-[1-(4-chloro-phenyl)-cyclopropyl]-ureido}-3-methyl-butyric acid methyl ester as colorless solid (500 mg). MS (ESI): 325.2 (MH+).

1. stirringstirring
2. waitwas continued at 90° C. for 20 hours
3. temperatureThe mixture was cooled
4. customThe layers were separated
5. washthe organic phase was washed with brine
6. dry with materialdried over Na2SO4
7. customevaporated
8. customThe residue was purified by flash chromatography
9. additionFractions containing the desired material
10. customevaporated