반응 #72544

ord-506deeb5f54946d7a3c2fa62f0204408

반응 조건

온도
-50°CELSIUS
상세 조건
See reaction.notes.procedure_details.

후처리

  1. 1
    온도maintaining the temperature between −60° C. and −55° C
  2. 2
    기타is brought to 0° C.
  3. 3
    workup.STIRRINGAfter stirring for 12 hours at ambient temperature
  4. 4
    기타the phases are separated
  5. 5
    세척the organic phase is washed successively with aq. 2M HCl solution, water
  6. 6
    건조The organic phase is dried over sodium sulphate
  7. 7
    여과filtered
  8. 8
    기타evaporated to dryness
  9. 9
    기타The residue obtained
  10. 10
    기타The crystals obtained
  11. 11
    여과are filtered off
  12. 12
    세척washed with ether
  13. 13
    기타dried in vacuo

실험 절차

To a solution of ethyl 4-amino-benzoate (40.0 g) in DCM (900 ml) at −60° C. there is added, dropwise, ethyl(methylsulphanyl)acetate (34.5 ml) under a nitrogen atmosphere. 29.0 g of tBuOCl are then added, dropwise, to the reaction mixture over 25 minutes, maintaining the temperature between −60° C. and −55° C. After stirring for one hour at −50° C., triethylamine (15.4 ml) is added dropwise. The reaction mixture is brought to 0° C. and then aqueous 3M HCl solution (485 ml) is added dropwise. After stirring for 12 hours at ambient temperature, the phases are separated and the organic phase is washed successively with aq. 2M HCl solution, water and then sat. aqueous NaCl solution. The organic phase is dried over sodium sulphate, filtered and evaporated to dryness. The residue obtained is taken up in ether. The crystals obtained are filtered off, washed with ether and dried in vacuo to yield the title product, which is used directly in the next Step.

출처

DOI: 10.6084/m9.figshare.5104873.v1특허: US08541412B2uspto-grants-2013_09