Hydrogen Peroxide → (2S,3S)-2-tert-butoxycarbonylamino-3-phenyl-pentanoic acid

Temperatur

-10 °C

To a solution of [(1S,2S)-1-((S)-2-oxo-4-phenyl-oxazolidine-3-carbonyl)-2-phenyl-butyl]-carbamic acid tert-butyl ester (4.38 g, 10 mmol) in a mixture of tetrahydrofuran and water (3:1, 60 mL) at −10° C. was added sequentially a solution of hydrogen peroxide in water (11 mL, 100 mmol, 30%) and an aqueous solution (15 mL) of lithium hydroxide monohydrate (1.23 g, 30 mmol). The reaction mixture was stirred at −10° C. and the progress of the reaction was monitored by thin layer chromatography. After 3 hours, TLC analysis indicated almost complete consumption of starting material. Saturated aqueous sodium sulfite solution (100 mL) was added. The mixture was concentrated to half of its original volume under reduced pressure to remove tetrahydrofuran and then extracted with dichloromethane (2×100 mL). The aqueous layer was separated, acidified to pH=2-3 with aqueous citric acid solution and extracted with ethyl acetate (2×300 mL). The organic layers were separated, combined and dried over sodium sulfate, concentrated under reduced pressure and dried in vacuo to give (2S,3S)-2-tert-butoxycarbonylamino-3-phenyl-pentanoic acid as a white foam (1.7 g, 58%).

1. customconsumption of starting material
2. additionSaturated aqueous sodium sulfite solution (100 mL) was added
3. concentrationThe mixture was concentrated to half of its original volume under reduced pressure
4. customto remove tetrahydrofuran
5. extractionextracted with dichloromethane (2×100 mL)
6. customThe aqueous layer was separated
7. extractionextracted with ethyl acetate (2×300 mL)
8. customThe organic layers were separated
9. dry with materialdried over sodium sulfate
10. concentrationconcentrated under reduced pressure
11. customdried in vacuo

ORD-Eintrag

ord-05158c7f278d44da93d662ea3b4bcf2b

Quelldatensatz

uspto-grants-2008_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07427635B2