Potassium Phosphate, Tribasic → (2R/S)-2-[4-(1-Hydroxy-2-methylpropyl)-phenyl]-propionic acid methyl ester

Experimental description: 150 mg ibuprofen methyl ester were dissolved in 1.4 mL ethanol and added to 150 mL potassium phosphate buffer pH 8.0. P450BM3 was added to the mixture at a final concentration of 10 μM. The mixture was split in 4 mL-aliquots into 15 mL scintillation vials equipped with a stir bar. 500 μL 10 mM NADPH in KPi buffer were added to each vial and stirred for 2 minutes. 500 μL cofactor regeneration solution containing 500 mM glucose-6-phosphate and 10 units/mL glucose-6-phosphate dehydrogenase were then added to each vial. The resulting mixtures were stirred at room temperature. After 48 hours, the reaction mixtures were joined together and extracted with chloroform (3×50 mL). The organic phase was then dried over magnesium sulfate (MgSO4) and evaporated in vacuo. Purification of the resulting oil by silica gel chromatography (5-40% ethyl acetate/hexane) afforded the activated product (methyl 2-(4′-(1″-hydroxy-2″-methylpropyl)phenyl)propanoate, 73 mg). 15 mg (0.06 mmol) of activated product were dissolved in 2 mL dry dichloromethane (CH2Cl2) and a catalytic amount (4 drops) of ethanol was added to the solution. The solution was cooled to −78° C. (dry ice) and added with 11 μL DAST (0.72 mmol). The reaction was stirred in dry ice for 16 hours. The reaction mixture was then added with 5 mL saturated sodium bicarbonate (NaHCO3) and extracted with dichloromethane (3×15 mL). The organic phase was then dried over magnesium sulfate (MgSO4) and evaporated in vacuo. Purification of the resulting oil by silica gel chromatography (0-30% ethyl acetate/hexane) afforded the fluorinated product, methyl 2-(4′-(1″-fluoro-2″-methylpropyl)phenyl)propanoate (10 mg, 65% yield, colorless oil). 1H-NMR (300 MHz, CDCl3): δ 0.84 (d, J=6.9 Hz, 3H, CH3), δ 1.01 (d, J=6.9 Hz, 3H, —CH3), δ 1.49 (d, J=8.7 Hz, 3H, CH3), δ 2.05-2.08 (m, 1H), δ 3.66 (s, 3H, OCH3), δ 3.73 (q, J=7.5 Hz, 1H), δ 5.07 (dd, J=40.0, J=6.9 Hz, 1H, CHF), δ 7.25 (m, 4H); 13C-NMR (75 MHz, CDCl3): δ 15.5, 17.82 (d), 18.54 (d), 34.48 (d, J: 85.7 Hz), 45.37, 52.31, 99.3 (d, J=174 Hz), 175.6; 19F-NMR (282 MHz, CDCl3): δ −179.8 (m). HRMS (EI+): exact mass calculated for C14H19FO2 requires m/z 238.1369, found 238.1367.

1. additionP450BM3 was added to the mixture at a final concentration of 10 μM
2. customThe mixture was split in 4 mL-aliquots into 15 mL scintillation vials
3. customequipped with a stir bar
4. addition500 μL 10 mM NADPH in KPi buffer were added to each vial and
5. addition500 μL cofactor regeneration solution containing 500 mM glucose-6-phosphate and 10 units/mL glucose-6-phosphate dehydrogenase
6. additionwere then added to each vial
7. stirringThe resulting mixtures were stirred at room temperature
8. waitAfter 48 hours
9. customthe reaction mixtures
10. extractionextracted with chloroform (3×50 mL)
11. dry with materialThe organic phase was then dried over magnesium sulfate (MgSO4)
12. customevaporated in vacuo
13. customPurification of the resulting oil by silica gel chromatography (5-40% ethyl acetate/hexane)

ORD-Eintrag

ord-bb1633d9547f487d8d54ac5d8e944e34

Quelldatensatz

uspto-grants-2012_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08252559B2