4-Fluoro-3-methoxybenzaldehyde → (4-Fluoro-3-methoxyphenyl)(3-fluoro-5-(1,1,2,2-tetrafluoroethoxy)phenyl)methanol

Temperatur

-72 °C

To a solution of 1-bromo-3-fluoro-5-(1,1,2,2-tetrafluoroethoxy)benzene, prepared as described in Procedure 3, (1.00 g, 3.44 mmol) in diethyl ether in (10 mL) at −72° C. was added 2.5 M n-BuLi (1.37 mL, 3.44 mmol) dropwise. Upon completion of addition, the reaction mixture was stirred for 15 minutes at −72° C., then 4-fluoro-3-methoxybenzaldehyde (0.53 g, 3.44 mmol) was added while the reaction mixture temperature was maintained below −52° C. The reaction mixture was stirred for 3 h at −72° C. The reaction mixture was quenched by the addition of 1N HCl and the aqueous portion was extracted with EtOAc (2×). The combined organic layers were washed with sat. NaCl, dried over MgSO4 and concentrated under reduced pressure. The residue was purified by ISCO using a gradient of 0-50% EtOAc/hexane as eluent to yield (4-fluoro-3-methoxyphenyl)(3-fluoro-5-(1,1,2,2-tetrafluoroethoxy)phenyl)methanol (0.83 g, 66% yield). HPLC: RT=3.85 min (Phenomenex Luna C18 5μ column, eluting with 10-90% aqueous methanol containing 0.1% phosphoric acid over a 4 minute gradient, flow rate 4 mL/min, monitoring at 220 nm); 1H NMR (CDCl3): 7.05-6.8 (m, 6H), 5.87 (tt, J=2.8, 52.9 Hz), 5.75 (s, 1H), 3.85 (s, 3H).

1. additionUpon completion of addition
2. temperaturewas maintained below −52° C
3. stirringThe reaction mixture was stirred for 3 h at −72° C
4. customThe reaction mixture was quenched by the addition of 1N HCl
5. extractionthe aqueous portion was extracted with EtOAc (2×)
6. washThe combined organic layers were washed with sat. NaCl
7. dry with materialdried over MgSO4
8. concentrationconcentrated under reduced pressure
9. customThe residue was purified by ISCO

ORD-Eintrag

ord-d13f4cbe84ea407bac01fa9bd21456f2

Quelldatensatz

uspto-grants-2014_02

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08642576B2