Hydrochloric Acid → 2-Chloro-6-fluoro-4-hydroxybenzaldehyde

Sec-BuLi (1.3M solution in cyclohexane, 42.3 mL, 55 mmol) was added slowly at −78° C. to a solution of intermediate 16, 1-(tert-Butyldimethylsilyl)oxy-3-chloro-5-fluorobenzene (13.1 g, 50 mmol) and TMEDA (8.3 mL, 55 mmol) in THF (200 mL) and the mixture was stirred at the same temperature for 30 min. DMF (4.23 mL, 55 mmol) was added to the mixture at −78° C., and the mixture was stirred at the same temperature for 1.5 h. Then 10% aqueous HCl was added to attain pH˜4-5 (200 mL), and the reaction mixture was stirred at RT for 12 h. Aqueous layer was extracted with EtOAc (200 mL). The organic layer was separated. The organic layer was washed with sat. NaHCO3, then H2O was added, HCl was added to attain pH˜3-4, the organic layer was separated, washed with brine, dried with Na2SO4 and evaporated in vacuo to give the title compound (7.53 g, 86%, 43 mmol) as a white solid. 1H NMR data (dmso-d6): 11.51 (br.s, 1H, OH), 10.15 (s, 1H, CHO), 6.78-6.83 (m, 1H, H—Ar), 6.68 (dd, 1H, J1=2.2 Hz, J2=12.7 Hz, H—Ar).

1. stirringthe mixture was stirred at the same temperature for 1.5 h
2. stirringthe reaction mixture was stirred at RT for 12 h
3. extractionAqueous layer was extracted with EtOAc (200 mL)
4. customThe organic layer was separated
5. washThe organic layer was washed with sat. NaHCO3
6. additionH2O was added
7. additionHCl was added
8. customthe organic layer was separated
9. washwashed with brine
10. dry with materialdried with Na2SO4
11. customevaporated in vacuo

ORD-Eintrag

ord-db921f4edcd840a4aa7a28e4550d0956

Quelldatensatz

uspto-grants-2010_10

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07812040B2