Reaction #801837

ord-ecaa32ef87e74fe78cc38da2bae338ca

Conditions

Detailed conditions
See reaction.notes.procedure_details.

Workup

  1. 1
    workup.ADDITIONwere added at RT
  2. 2
    ExtractionThe mixture was extracted with 15 ml of ethyl acetate
  3. 3
    Washthe organic phase was washed in each case once with 5 ml of 10% strength sodium dithionite solution and 5 ml of saturated sodium chloride solution
  4. 4
    DryingThe organic phase was dried over sodium sulfate
  5. 5
    Filtrationfiltered
  6. 6
    Concentrationconcentrated under reduced pressure
  7. 7
    OtherThe crude product was purified by chromatography on silica gel (mobile phase
  8. 8
    OtherWork-up gave

Procedure

585 mg (3.89 mmol) of sodium bromate were initially charged in 2 ml of water, and 300 mg (1.29 mmol) of ethyl 2-(trifluoromethyl)phenylacetate, dissolved in 2.5 ml of ethyl acetate, were added at RT. A solution of 403 mg (3.89 mmol) of sodium bisulfite in 3.8 ml of water was then added slowly. The mixture was stirred at RT for 18 h. 5 ml of 10% strength aqueous sodium dithionite solution were then added. The mixture was extracted with 15 ml of ethyl acetate, and the organic phase was washed in each case once with 5 ml of 10% strength sodium dithionite solution and 5 ml of saturated sodium chloride solution. The organic phase was dried over sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified by chromatography on silica gel (mobile phase: cyclohexane/ethyl acetate 20:1, then 10:1). This gave 186 mg of a mixture consisting of the title compound and the starting material ethyl 2-(trifluoromethyl)phenylacetate (ratio 16:84 according to GC/MS [Method 20]). This mixture was once more reacted with 362 mg (2.40 mmol) of sodium bromate and 250 mg (2.40 mmol) of sodium bisulfite according to the procedure described above. Work-up gave a mixture of 31% title compound and 69% ethyl 2-(trifluoromethyl)phenylacetate, which was reacted further without any further purification.

Source

DOI: 10.6084/m9.figshare.5104873.v1Patent: US09187466B2uspto-grants-2015_11