反应详情

To a solution of 3-(4-bromo-phenyl)-3-o-tolyl-propionic acid (3.7 g) in DMF (45 mL) was added TBTU (5.2 g) and Et3N (4.8 mL) at 0° C. The reaction mixture was stirred at rt for 10 min and again cooled down to 0° C. N,O-dimethylhydroxylamine hydrochloride (1.36 g) was added and the mixture was stirred at rt for 1.5 hour. A saturated solution of NH4Cl was added, the phases were separated and the inorganic one was extracted with EtOAc (2×). The combined organic layers were washed with brine, dried over Na2SO4, filtered and concentrated in vacuo. The crude product was purified by flash chromatography on silica gel (EtOAc/n-heptane 1:2) to yield the title compound as a colorless oil (4.1 g, 97%), MS (ESI+): m/z=362.0750 ([M+H]+, 1Br).

1. temperatureagain cooled down to 0° C
2. stirringthe mixture was stirred at rt for 1.5 hour
3. customthe phases were separated
4. extractionthe inorganic one was extracted with EtOAc (2×)
5. washThe combined organic layers were washed with brine
6. dry with materialdried over Na2SO4
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe crude product was purified by flash chromatography on silica gel (EtOAc/n-heptane 1:2)