反应详情

Sodium hydride (80% disp. in oil; 933 mg, 31.1 mmol) was added, all at once to 3,4-dimethoxybenzyl alcohol (3.48 g, 20.7 mmol) in DMF (40 mL) at 0° C. and under Ar. After 5 min., the mixture was allowed to warm to r.t. After 1 h, 1-bromo-3,5-difluorobenzene (4 g, 20.7 mmol) in DMF (5 mL) was added dropwise at r.t. The resulting mixture was kept at this temperature for 16 h and slowly poured into H2O (500 mL). It was extracted with EtOAc (3×) and the combined organics were washed with 25% NH4OAc buffer (1×), H2O (2×) and brine. The solution was dried (MgSO4) and concentrated to give a pale yellow solid that was purified by column chromatography on silica gel (EtOAc:hexane, 10:90-15:85) to afford the title compound as a white solid (5.85 g, 83%).

1. customat 0° C.
2. waitAfter 1 h
3. waitThe resulting mixture was kept at this temperature for 16 h
4. extractionIt was extracted with EtOAc (3×)
5. washthe combined organics were washed with 25% NH4OAc buffer (1×), H2O (2×) and brine
6. dry with materialThe solution was dried (MgSO4)
7. concentrationconcentrated
8. customto give a pale yellow solid
9. customthat was purified by column chromatography on silica gel (EtOAc:hexane, 10:90-15:85)