反应详情

To a stirred solution of 5-oxo-1-(3-trifluoromethyl-phenyl)-pyrrolidine-3-carboxylic acid (1.0 g, 3.66 mmol) in DCM (10 ml) was added thionyl chloride (0.9 ml, 12.44 mmol) and DMF (2 drops). The reaction mixture was stirred for 1 hr at room temperature and the solvents were removed. The residue was taken in toluene (10 ml) and again concentrated to obtain brown oil. The resulting oil was taken in acetonitrile (10 ml) and trimethylsilyldiazomethane (9.15 ml, 18.3 mmol). It was stirred at room temperature for 1 hr. The reaction mixture was cooled to 0° C. and 33% HBr in acetic acid (4.17 ml, 23.79 mmol) was added drop wise and stirred for 1 hr at room temperature. To the reaction mixture sodium bicarbonate (20 ml) was added and extracted with ethyl acetate (3×15 ml). The combined organic layer was washed with saturated brine solution (35 ml). The organic layer was dried over Na2SO4, evaporated to obtain crude product. The crude product was purified by column chromatography using silicagel (100-200) and 12 to 16% ethyl acetate in hexane as an eluent to obtain 4-(2-bromo-acetyl)-1-(3-trifluoromethyl-phenyl)-pyrrolidin-2-one (0.9 g, 72%) as a brown mass.

1. customthe solvents were removed
2. concentrationagain concentrated
3. customto obtain brown oil
4. stirringIt was stirred at room temperature for 1 hr
5. temperatureThe reaction mixture was cooled to 0° C.
6. stirringstirred for 1 hr at room temperature
7. extractionextracted with ethyl acetate (3×15 ml)
8. washThe combined organic layer was washed with saturated brine solution (35 ml)
9. dry with materialThe organic layer was dried over Na2SO4
10. customevaporated
11. customto obtain crude product
12. customThe crude product was purified by column chromatography