反应详情

DMSO (20 ml) was added slowly to a mixture of sodium hydride (0.215 g, 5.37 mmol) and trimethylsulfoxonium iodide (1.227 g, 5.58 mmol). The mixture was stirred at room temperature for 15 min, and then (E)-methyl 3-(5-bromopyridin-3-yl)acrylate (1 g, 4.13 mmol) in DMSO (8 ml) was added. The reaction mixture was stirred at room temperature for 3 min. Ice water and EtOAc were added. The organic layer was washed with water and brine. The aqueous layer was extracted with EtOAc twice. The combined organic layer was dried over Na2SO4, filtered and concentrated. The residue was purified via flash column (EtOAc/Heptane=0-30%, v/v) to give methyl 2-(5-bromopyridin-3-yl)cyclopropanecarboxylate (257 mg, 1.004 mmol, 24% yield). ESI-MS m/z: 358[M+1]+; 1H NMR (CDCl3, 400 MHz); 1.33-1.38 (m, 1H), 1.66-1.71 (m, 1H), 1.94-1.98 (m, 1H), 2.49-2.54 (m, 1H), 3.75 (s, 3H), 7.51 (t, J=2.0 Hz, 1H), 8.37 (d, J=2.0 Hz, 1H), 8.53 (t, J=2.0 Hz, 1H).

1. stirringThe reaction mixture was stirred at room temperature for 3 min
2. washThe organic layer was washed with water and brine
3. extractionThe aqueous layer was extracted with EtOAc twice
4. dry with materialThe combined organic layer was dried over Na2SO4
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue was purified via flash column (EtOAc/Heptane=0-30%, v/v)