反应详情

温度

-78 °C

To a solution of 2.5 M of n-BuLi in hexanes (10 mL) in THF (50 mL) was added 2,2,66-tetramethyl-piperidine (5.3 mL, 0.031 mol) slowly at −78° C. The cooling bath was replaced by an ice-water bath for 30 min and the solution was re-cooled to −78° C. After 5 min a solution of 2-chloropyrazine (2.3 mL, 0.026 mol) in THF (10 mL) is added. The reaction mixture turned brown in color. After 10 min, 4-formyldiphenyl ether (6.2 g, 0.031 mol) was added slowly. The reaction mixture was stirred at −78° C. for 2.5 h. The reaction mixture was quenched using sat. aq. NH4Cl at −78° C. After warming up to rt, the reaction mixture was concentrated under vacuo and purified by flash column chromatography (eluting with 10% EtOAc in hexanes) to afford the title compound. 1H NMR (400 MHz, CDCl3): δ 6.02 (s, 1H), 6.93-6.98 (m, 2H), 7.00 (d, J=7.58 Hz, 2H), 7.12 (t, J=7.33 Hz, 1H), 7.29-7.37 (m, 4H), 8.39 (d, J=2.53 Hz, 1H), 8.58 (d, J=2.53 Hz, 1H). MS (ES+): m/z 295.08 (100)[M-18]. HPLC: tR=3.46 min (Open lynx, polar—5 min).

1. waitAfter 10 min
2. customThe reaction mixture was quenched
3. customat −78° C
4. temperatureAfter warming up to rt
5. concentrationthe reaction mixture was concentrated under vacuo
6. custompurified by flash column chromatography (eluting with 10% EtOAc in hexanes)