Hydrogen Peroxide → 2(R)-cyclopentylmethyl-3(S)-hydroxyl-5-phenylpentanoic acid

Temperatur

0 °C

Acyloxazolidinone 3 (226 mg, 0.500 mmol) was dissolved in 3 mL of THF and 1 mL of distilled water. The resulting solution was cooled to 0° C. To this solution was added 30% aqueous hydrogen peroxide (0.40 mL, 4.0 mmol), followed by a solution of lithium hydroxide (19 mg, 0.80 mmol) in 0.5 mL of distilled water. After the solution was stirred for 16 h, sodium sulfite (567 mg, 4.50 mmol) in 3 mL of distilled water was added. The bulk of tetrahydrofuran was removed under reduced pressure, and the resulting mixture (pH 12˜13) was extracted with three 20 mL portion of methylene chloride to remove the oxazolidinone auxiliary. The aqueous layer was cooled in an ice bath and acidified to pH 1 with 6 M aqueous hydrochloric acid. The resulting cloudy solution was extracted with five portion of 30 mL ethyl acetate. The combined organic layers are dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to yield 230 mg (81%) of the desired acid 4 as a white solid. 1H NMR (300 MHz, CDCl3) δ 7.18-7.35 (5H, m), 3.87 (1H, m), 2.81-2.87 (1H, m), 2.60-2.76 (1H, m); 2.54-2.60 (1H, m), 1.00-1.95 (m, 13H).

1. customThe bulk of tetrahydrofuran was removed under reduced pressure
2. extractionthe resulting mixture (pH 12˜13) was extracted with three 20 mL portion of methylene chloride
3. customto remove the oxazolidinone auxiliary
4. temperatureThe aqueous layer was cooled in an ice bath
5. extractionThe resulting cloudy solution was extracted with five portion of 30 mL ethyl acetate
6. dry with materialThe combined organic layers are dried over anhydrous magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated under reduced pressure

ORD-Eintrag

ord-f7aaec7a08ae46ba95c15ad2deeb59ac

Quelldatensatz

uspto-grants-2008_03

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07342008B2