Reaktion #5665

Reaktionsgleichung

benzyl alcohol

benzyl 2,3,4,6-tetrafluorobenzoate

water

sodium hydride

→

6-benzyloxy-2,3,4-trifluorobenzoic acid

Ausbeute 31.6%

Lösungsmittel

n-hexane

acetic acid

acetic acid

benzene

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added
2. 2
   Sonstigereacted
3. 3
   Sonstigefollowed by the removal of the solvent by distillation
4. 4
   workup.ADDITIONTo the residue, 6.5 g of potassium hydroxide and 50 ml of water and 100 ml of methanol were added
5. 5
   SonstigeThey were reacted at 50° C. for 30 minutes
6. 6
   Sonstigefollowed by the removal of the solvent by distillation
7. 7
   workup.ADDITIONTo the residue were added 50 ml of benzene and 7% aq. potassium hydroxide solution
8. 8
   workup.STIRRINGThe resultant mixture was shaken
9. 9
   Sonstigefollowed by separation into two layers
10. 10
    workup.ADDITIONConcentrated hydrochloric acid was added to the water layer so that the water layer
11. 11
    ExtraktionThe thus-acidified water layer was extracted twice with 100 ml portions of chloroform
12. 12
    workup.ADDITIONThe extract was treated with anhydrous magnesium sulfate
13. 13
    workup.DISTILLATIONthe solvent was distilled out
14. 14
    SonstigeA solid thus formed
15. 15
    Filtrationcollected by filtration

Vorschrift

6.5 g of benzyl alcohol was dissolved in 150 ml of benzene. While the resultant solution was cooled with water, 2.4 g of sodium hydride (60%) was added and reacted. To the reaction mixture was added 15 g of benzyl 2,3,4,6-tetrafluorobenzoate, and stirred at room temperature for 1 hour. 3.6 g of acetic acid was added, followed by the removal of the solvent by distillation. To the residue, 6.5 g of potassium hydroxide and 50 ml of water and 100 ml of methanol were added. They were reacted at 50° C. for 30 minutes. 6 g of acetic acid was added, followed by the removal of the solvent by distillation. To the residue were added 50 ml of benzene and 7% aq. potassium hydroxide solution. The resultant mixture was shaken, followed by separation into two layers. Concentrated hydrochloric acid was added to the water layer so that the water layer was rendered acidic. The thus-acidified water layer was extracted twice with 100 ml portions of chloroform. The extract was treated with anhydrous magnesium sulfate and the solvent was distilled out. A solid thus formed was dispersed in n-hexane and then collected by filtration, whereby 4.7 g of 6-benzyloxy-2,3,4-trifluorobenzoic acid was obtained as colorless powder.

Quelle