Hydrogen Peroxide → (R)-3-cyclopentyl-2-phenyl-propionic acid

Temperature

0 °C

Lithium hydroxide monohydrate (1.28 g, 30.6 mmol) is suspended in THF (50 mL) and cooled to 0° C. Hydrogen peroxide (50 wt % in water, 2.81 mL, 91.79 mmol) is added dropwise. Reaction is stirred at 0° C. for 15 min and the title C compound, (4R,5S)-3-((R)-3-cyclopentyl-2-phenyl-propionyl)-4-methyl-5-phenyl-oxazolidin-2-one (3.85 g, 10.2 mmol) is added in five separate portions, allowing portions to dissolve completely between additions. The reaction is allowed to stir and warm to RT overnight. The reaction is then concentrated to a sticky white solid. This is dissolved in ethyl acetate (25 mL)/1 N HCl (25 mL). The organic solution is dried over anhydrous sodium sulfate, filtered, and concentrated to afford the crude product as a yellow oil. The crude product is chromatographed over silica eluting with 5→65% ethyl acetate in hexanes to afford (R)-3-cyclopentyl-2-phenyl -propionic acid as a white solid: 1H NMR (400 MHz, CDCl3) δ 1.1 (m, J=11.6, 7.8, 7.8, 3.9 Hz, 2 H) 1.5 (m, 2 H) 1.6 (m, 2 H) 1.7; LC/MS 217.2 (M−1).

1. customReaction
2. customseparate portions
3. dissolutionto dissolve completely between additions
4. stirringto stir
5. temperaturewarm to RT overnight
6. concentrationThe reaction is then concentrated to a sticky white solid
7. dissolutionThis is dissolved in ethyl acetate (25 mL)/1 N HCl (25 mL)
8. dry with materialThe organic solution is dried over anhydrous sodium sulfate
9. filtrationfiltered
10. concentrationconcentrated
11. customto afford the crude product as a yellow oil
12. customThe crude product is chromatographed over silica eluting with 5→65% ethyl acetate in hexanes

ORD record

ord-c86151cef6fd445e9bf1b33d58a57d9c

Source dataset

uspto-grants-2012_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08252931B2