反应详情

A solution of [(S)-1-(4-bromo-phenyl)-ethyl]-[2-(2-chloro-5-methoxy-4-nitro-phenyl)-ethyl]-carbamic acid tert-butyl ester (0.66 g, 1.17 mmol), N-Boc piperazine (0.44 g, 2.34 mmol), cesium carbonate (0.96 g, 2.92 mmol) and devphos (46.1 mg, 0.117 mmol) in 1,4-dioxane (5 mL) was degassed with argon. Pd2(dba)3 (0.054 g, 0.058 mmol) was added and the mixture heated to reflux for 3 hours under an argon atmosphere. The mixture was allowed to cool to room temperature, diluted with water (30 mL) and extracted with EtOAc (3×30 mL). The combined organic extracts were washed with brine, dried (Na2SO4) and concentrated under reduced pressure. The residue was purified by column chromatography on silica gel using 20% EtOAc in hexane to give the title compound (0.33 g, 46%).

1. temperaturethe mixture heated
2. temperatureto reflux for 3 hours under an argon atmosphere
3. extractionextracted with EtOAc (3×30 mL)
4. washThe combined organic extracts were washed with brine
5. dry with materialdried (Na2SO4)
6. concentrationconcentrated under reduced pressure
7. customThe residue was purified by column chromatography on silica gel using 20% EtOAc in hexane