Réaction #2146691

Équation de réaction

4′-benzoyloxyacetophenone

tetra-n-butyl ammonium tribromide

→

4′-benzoyloxy-2-bromoacetophenone

Rendement 73.5%

Solvants

methanol

Conditions de réaction

Traitement

1. 1
   workup.DISTILLATIONwas distilled off under reduced pressure
2. 2
   Autreto remove the solvent
3. 3
   workup.DISSOLUTIONThe residue was dissolved in ethyl acetate
4. 4
   Lavagewashed twice with water
5. 5
   Lavagewashed with an aqueous saturated sodium chloride solution
6. 6
   SéchageAfter the ethyl acetate layer was dried over anhydrous sodium sulfate
7. 7
   Concentrationconcentrated under reduced pressure
8. 8
   Autrethe resulting crude product was purified by silica gel column chromatography (elution solvent: hexane/methylene chloride=1/1)

Mode opératoire

13.50 g (corresponding to 59.66 mmol) of 4′-benzoyloxyacetophenone was dissolved in 1100 ml of methanol, and 34.52 g (corresponding to 71.59 mmol) of tetra-n-butyl ammonium tribromide was added thereto. The mixture was stirred overnight at room temperature, and was distilled off under reduced pressure to remove the solvent. The residue was dissolved in ethyl acetate and washed twice with water and then washed with an aqueous saturated sodium chloride solution. After the ethyl acetate layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure, the resulting crude product was purified by silica gel column chromatography (elution solvent: hexane/methylene chloride=1/1), to obtain 13.38 g (corresponding to 43.84 mmol) of 4′-benzoyloxy-2-bromoacetophenone (FIG. 3, Step 4).

Source