反应详情

To a stirred solution of tert-butyl 2-((diphenylmethylene)amino)acetate (1 g, 3.39 mmol) in THF (20 ml) cooled to −78° C. under nitrogen atmosphere was added LDA, 2M in THF/heptane/ethylbenzene (2.54 ml, 5.08 mmol) dropwise for 30 mins. To this mixture was then added 3,3,3-trifluoropropyl trifluoromethanesulfonate (1.083 g, 4.40 mmol). The reaction was gradually warmed to rt and stirred for 4 h. The reaction mixture was quenched by addition of saturated aqueous ammonium chloride at 0° C. The reaction mixture was then extracted with ethyl acetate (3×10 mL). The combined organic extracts were washed with water and brine, dried over sodium sulfate and then concentrated under reduced pressure. The crude product was purified by silica gel column chromatography using 2% ethyl acetate in hexane to afford tert-butyl 2-((diphenylmethylene)amino)-5,5,5-trifluoropentanoate (800 mg, 2.02 mmol, 60% yield) as a yellow oil. LCMS (ESI) m/e 391.9 [(M+H)+, calcd for C22H24F3NO2, 392.2]; LC/MS retention time (method E): tR=2.49 min.

1. customThe reaction mixture was quenched by addition of saturated aqueous ammonium chloride at 0° C
2. extractionThe reaction mixture was then extracted with ethyl acetate (3×10 mL)
3. washThe combined organic extracts were washed with water and brine
4. dry with materialdried over sodium sulfate
5. concentrationconcentrated under reduced pressure
6. customThe crude product was purified by silica gel column chromatography