Ammonium Chloride → tert.-butyl (S)-3-(4-amino-3-chloro-5-trifluoromethyl-benzyl)-4-((R)-4-benzyl-2-oxo-oxazolidin-3-yl)-4-oxo-butanoate

Temperature

-78 °C

Under an argon atmosphere 63.24 mL (63.24 mmol) of a sodium-bis(trimethylsilyl)-amide solution (1 M in THF) was added dropwise to a solution of 22.5 g (52.71 mmol) of (R)-3-[3-(4-amino-3-chloro-5-trifluoromethyl-phenyl)-propionyl]-4-benzyl-oxazolidin-2-one in 105 mL THF which had been cooled to −78° C. and the mixture was stirred for 2 h at −78° C. 38.9 mL (263.5 mmol) of tert.butyl bromoacetate were added dropwise to the reaction mixture at −78° C., this was stirred for a further 24 h at −78° C. and then heated to RT. After the addition of 200 mL of a saturated NH4Cl solution the mixture was extracted twice with 300 mL of EtOAc, the combined org. phases were dried over Na2SO4 and evaporated down i. vac. The residue remaining was purified by chromatography on silica gel. The desired product was obtained in the form of a yellow oil.

1. stirringthis was stirred for a further 24 h at −78° C.
2. temperatureheated to RT
3. extractionwas extracted twice with 300 mL of EtOAc
4. dry with materialphases were dried over Na2SO4
5. customevaporated down i
6. customThe residue remaining was purified by chromatography on silica gel

ORD record

ord-4053ff63a8b3459eafa531d30f92baf3

Source dataset

uspto-grants-2009_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07595312B2