Reacción #489024

ord-9261035a7d5e42debb4e039380e90426

Condiciones de reacción

Temperatura
-78°CELSIUS
Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    OtroThe cold bath was removed
  2. 2
    workup.STIRRINGto stir at room temperature for 1 h, whereupon saturated NH4Cl solution (200 mL)
  3. 3
    workup.ADDITIONwas added
  4. 4
    OtroMost of the THF was removed under vacuum
  5. 5
    Otrothe mixture was partitioned between ether and brine
  6. 6
    SecadoAfter drying over Na2SO4
  7. 7
    Concentraciónthe organic layer was concentrated
  8. 8
    Otrothe residue purified by silica gel chromatography (20% EtOAc in hexanes)

Procedimiento

(S)-4-Benzyloxazolidin-2-one (35 g, 0.2 mol) was dissolved in THF (500 mL) and cooled to −78° C. A solution of nBuLi in hexane (80 mL, 0.2 mol) was added dropwise. The solution was stirred at this temperature for 30 min and then (E)-but-2-enoyl chloride (19 mL, 0.2 mol) was added slowly. The cold bath was removed and the reaction was allowed to stir at room temperature for 1 h, whereupon saturated NH4Cl solution (200 mL) was added. Most of the THF was removed under vacuum and the mixture was partitioned between ether and brine. After drying over Na2SO4, the organic layer was concentrated and the residue purified by silica gel chromatography (20% EtOAc in hexanes) to give the desired product (39 g, 79% yield) as a white solid.

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US08741946B2uspto-grants-2014_06