反应详情

温度

-78 °C

To a stirred solution of 2,5-dibromopyridine (5.00 g, 21.11 mmol) in anhydrous toluene (300 mL) at −78° C. under nitrogen was slowly added a solution of n-BuLi (10.13 mL, 25.33 mmol, 2.5M in hexanes). After 2 h at −78° C., methyl disulfide (2.47 mL, 27.44 mmol) was added. The reaction mixture was stirred for 1 h at −78° C. and was allowed to warm to room temperature, quenched with saturated NH4Cl to form a two-phase system. The organic layer was separated, washed with sat NH4C1, H2O and brine, dried over anhydrous MgSO4, filtered and concentrated. The residue was purified by flash chromatography on silica gel (AcOEt/hexane, 5/95) to afford the title compound 50 (2.74 g, 13.43 mmol, 64% yield) as a pale yellow oily liquid. 1H NMR (400 MHz, CDCl3) δ(ppm): 8.49 (dd, J=2.3, 0.6 Hz, 1H), 7.60 (dd, J=8.5, 2.4 Hz, 1H), 7.09 (dd, J=8.6, 0.8 Hz, 1H), 2.57 (s, 3H).

1. temperatureto warm to room temperature
2. customquenched with saturated NH4Cl
3. customto form a two-phase system
4. customThe organic layer was separated
5. washwashed with sat NH4C1, H2O and brine
6. dry with materialdried over anhydrous MgSO4
7. filtrationfiltered
8. concentrationconcentrated
9. customThe residue was purified by flash chromatography on silica gel (AcOEt/hexane, 5/95)