Reacción #72569

ord-8253b3b8bacd438ab0b3414223283023

Disolventes

Condiciones de reacción

Temperatura
-60°CELSIUS
Condiciones detalladas
See reaction.notes.procedure_details.

Tratamiento posterior

  1. 1
    Otrothe temperature between −60° C. and −55° C
  2. 2
    Otrois brought to ambient temperature
  3. 3
    workup.STIRRINGstirring
  4. 4
    workup.WAITis carried out for a further 2 hours
  5. 5
    OtroThe organic phase is evaporated
  6. 6
    Extracciónthe aqueous suspension is extracted with DCM
  7. 7
    Lavadowashed with 2M HCl solution
  8. 8
    Secadowith saturated NaCl solution, dried over sodium sulphate
  9. 9
    Filtraciónfiltered
  10. 10
    Otroevaporated to dryness
  11. 11
    OtroThe residue is triturated in ethyl ether
  12. 12
    Filtraciónfiltered
  13. 13
    Otrodried in vacuo

Procedimiento

Ethyl(methylsulphanyl)acetate (27.31 mmoles) is added dropwise to a solution of the compound obtained in Step E (23.75 mmoles) in THF (200 ml) at −60° C. under a nitrogen atmosphere. tBuOCl (27.31 mmoles) is added dropwise to the reaction mixture over 20 minutes, keeping the temperature between −60° C. and −55° C. After stirring for 3 hours at −60° C., triethylamine (29.68 mmoles) is added dropwise. The reaction mixture is brought to ambient temperature; aqueous 3M HCl solution (340 ml) is then added and stirring is carried out for a further 2 hours. The organic phase is evaporated and the aqueous suspension is extracted with DCM. The organic phases are combined, then washed with 2M HCl solution and then with saturated NaCl solution, dried over sodium sulphate, filtered and evaporated to dryness. The residue is triturated in ethyl ether, filtered and dried in vacuo to yield the title product, which is used directly in the next Step.

Fuente

DOI: 10.6084/m9.figshare.5104873.v1Patente: US08541412B2uspto-grants-2013_09