Dimethylformamide → 2-Fluoro-3-phenoxybenzaldehyde

Temperatur

-78 °C

Cool a solution of 2,2,6,6-tetramethylpiperidine (5.1 mL, 30.0 mmol) in THF (40 mL) to −78° C. Add dropwise n-Butyllithium (18.7 mL, 30.0 mmol, 1.6M in hexanes) and stir for 10 min at −78° C. Add dropwise 2-fluorophenyl phenyl ether (4.7 g, 25.0 mmol), stir 2 h at −78° C. Add N,N-dimethylformamide (2.3 mL, 30.0 mmol) dropwise over 15 min. Stir the resulting mixture for 3 h at −78° C. and allow to warm to ambient temperature over 16 h. Quench the reaction mixture with water (50 mL), extract with ethyl acetate, dry over Na2SO4, filter and concentrate under reduced pressure to give an oil. Crystallize the oil with hexanes to give a solid, collect and recrystallize from hexanes/ethyl acetate/methylene chloride to give the title compound: mp 75-77° C.; MS (m/e): 216 (M+); Calculated for C13H9FO2: Calcd: C, 72.22; H, 4.20. Found: C, 72.41; H, 4.23. Purification of the mother liquors by silica gel chromatography (2-3% ethyl acetate/hexanes) gives an additional amount of the title compound: MS (m/e): 216 (M+).

1. stirringstir 2 h at −78° C
2. stirringStir the resulting mixture for 3 h at −78° C.
3. temperatureto warm to ambient temperature over 16 h
4. customQuench the reaction mixture with water (50 mL)
5. extractionextract with ethyl acetate
6. dry with materialdry over Na2SO4
7. filtrationfilter
8. concentrationconcentrate under reduced pressure
9. customto give an oil
10. customCrystallize the oil with hexanes
11. customto give a solid
12. customcollect
13. customrecrystallize from hexanes/ethyl acetate/methylene chloride

ORD-Eintrag

ord-55c190e5e1234ef4943f7c7239befb4e

Quelldatensatz

uspto-grants-2011_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08044090B2