反应 #1435771

ord-869dac237d604566ac448f3c86457951

反应条件

温度
0°CELSIUS
详细条件
See reaction.notes.procedure_details.

后处理

  1. 1
    workup.WAITthe reaction mixture was left
  2. 2
    温度to warm to room temperature
  3. 3
    workup.STIRRINGAfter stirring for 18 hours
  4. 4
    其他was evaporated under reduced pressure
  5. 5
    其他the residue triturated in ether at 0° C
  6. 6
    过滤The precipitated triphenylphosphinoxide was filtered
  7. 7
    洗涤washed with ether
  8. 8
    其他The combined filtrates were evaporated
  9. 9
    其他to yield 12.8 g of the crude product as a brown-yellow oil
  10. 10
    其他The crude product was purified by chromatography on silica gel

实验过程

Under an inert atmosphere, a solution of 6.5 g (25 mmol) of triphenylphosphine in 20 ml of tetrahydrofurane was treated with at 0° C. with 3.9 ml (25 mmol) of diethyl azodicarboxylate. Thereupon, 3.0 g (17 mmol) of 2-chloro-6-nitrophenol were added and the reaction mixture was stirred at 0° C. for 15 minutes. Finally, 4.93 g (17 mmol) of (S)-2-tert-butoxycarbonylamino-3-hydroxy-propionic acid benzyl ester were added and the reaction mixture was left to warm to room temperature. After stirring for 18 hours, for the working-up the solvent was evaporated under reduced pressure and the residue triturated in ether at 0° C. The precipitated triphenylphosphinoxide was filtered and washed with ether. The combined filtrates were evaporated to yield 12.8 g of the crude product as a brown-yellow oil. The crude product was purified by chromatography on silica gel using heptane and ethyl acetate as the eluent. There were obtained 3.9 g (50%) of the title compound as a yellow oil, [α]589=−5.96° (c=1.0% in MeOH), MS m/e (%): 468.1 (M+NH4+, 100).

来源

DOI: 10.6084/m9.figshare.5104873.v1专利: US07211573B2uspto-grants-2007_05