反应详情

温度

0 °C

A solution of 4-fluoro-benzoic acid methyl ester (19.1 g, 114 mmol) in THF (300 mL) at −78° C. is treated with ethylmagnesium bromide (135 mL, 3.0 M). The reaction mixture is allowed to warm to 0° C. over 30 min and quenched with HCl (350 mL, 1.0 M). THF is removed under vacuum, and the residue is extracted with EtOAc (3×100 mL). The organic layer is dried over Na2SO4 and concentrated. The intermediate tertiary alcohol is dissolved in CH2Cl2 (200 mL), cooled to −40° C., and treated with BF3-Et2O (11.5 g, 91.0 mol). The reaction mixture is allowed to warm to 0° C. over 30 min and quenched with water (50 mL). The organic layer is dried over Na2SO4 and concentrated. The residue is purified using silica gel column chromatography (5% EtOAc/Hex) to afford the title compound (16.8 g, 90%).

1. customquenched with HCl (350 mL, 1.0 M)
2. customTHF is removed under vacuum
3. extractionthe residue is extracted with EtOAc (3×100 mL)
4. dry with materialThe organic layer is dried over Na2SO4
5. concentrationconcentrated
6. dissolutionThe intermediate tertiary alcohol is dissolved in CH2Cl2 (200 mL)
7. temperaturecooled to −40° C.
8. temperatureto warm to 0° C. over 30 min
9. customquenched with water (50 mL)
10. dry with materialThe organic layer is dried over Na2SO4
11. concentrationconcentrated
12. customThe residue is purified