Acetic Acid → HCID 18700104, Verbindung

Temperatur

-78 °C

To a stirred solution of 4-bromo-1-(tert-butyldimethylsilyloxymethyl)-2-trifluoromethoxybenzene (5.5 g, 15 mmol) from Step 3 above in THF (100 mL) at -78° C. was added n-butyllithium (6.6 mL of a 2.5 M solution in hexanes, 16.5 mmol) dropwise over a period of 10 min. The resulting pale yellow solution was stirred at -78° C. for 30 min and trimethylborate (1.75 g, 17 mmol) was added. The resulting solution was stirred at -78° C. for 5 min and then warmed to ambient temperature for 45 min. To the mixture was added acetic acid (0.90 mL, 15 mmol) and hydrogen peroxide (0.1.7 mL of a 30% solution in water, 17 mmol) and stirring was continued for 1 h. The solvent was removed under reduced pressure and the residue was partitioned between EtOAc (150 mL) and water (2×50 mL). The organic layer was dried (MgSO4), filtered, and the solvent was removed under reduced pressure. The residue was purified by pressurized silica gel column chromatography using 10% EtOAc:hexanes as eluant to give 4-hydroxy-1-(tert-butyldimethylsilyloxymethyl)-2-trifluoromethoxy-benzene as a colorless oil (TLC Rf =0.40 (10% EtOAc:hexanes)).

1. stirringThe resulting solution was stirred at -78° C. for 5 min
2. temperaturewarmed to ambient temperature for 45 min
3. stirringstirring
4. waitwas continued for 1 h
5. customThe solvent was removed under reduced pressure
6. customthe residue was partitioned between EtOAc (150 mL) and water (2×50 mL)
7. dry with materialThe organic layer was dried (MgSO4)
8. filtrationfiltered
9. customthe solvent was removed under reduced pressure
10. customThe residue was purified by pressurized silica gel column chromatography

ORD-Eintrag

ord-ca1a017ccf3347798652aac533aac49e

Quelldatensatz

uspto-grants-2000_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US06090805