Reaktion #700932

Reaktionsgleichung

trifluoroacetic acid

2-(4Chlorophenyl)ethanol

hydrochloric acid

t-Butylbromoacetate

→

subtitle compound

2-[2-(4-Chlorophenyl)ethoxy]acetic acid

Lösungsmittel

Water

sodium hydroxide

toluene

dichoromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGstirring
2. 2
   workup.WAITcontinued for 18 hours
3. 3
   Temperaturwas cooled in ice
4. 4
   SonstigeThe organic layer was separated
5. 5
   Extraktionthe aqueous extracted with ethyl acetate
6. 6
   WaschenThe combined organic extracts were washed with brine
7. 7
   Trocknendried (MgSO4)
8. 8
   SonstigeThe solvent was removed in vacuo
9. 9
   Sonstigeto give a pale yellow oil
10. 10
    Temperaturthe mixture was heated
11. 11
    Temperaturat reflux for 1 hour
12. 12
    SonstigeThe volatiles were removed in vacuo
13. 13
    Waschenwashed with ethyl acetate
14. 14
    Extraktionextracted with ethyl acetate
15. 15
    Waschenthis ethyl acetate was washed with water
16. 16
    Trocknendried (MgSO4)
17. 17
    Sonstigethe volatiles removed in vacuo

Vorschrift

2-(4Chlorophenyl)ethanol (10 g) was stirred in 50% aqueous sodium hydroxide (70 ml), tetrabutylammoniumbromide (1.4 g) was added and the mixture stirred for 1 hour. t-Butylbromoacetate (28.6 ml) in toluene (140 ml) was added and stirring continued for 18 hours. Water (50 ml) was added and after 2 hours the mixture was cooled in ice and acidified to pH 1 with concentrated hydrochloric acid. The organic layer was separated and the aqueous extracted with ethyl acetate. The combined organic extracts were washed with brine and dried (MgSO4). The solvent was removed in vacuo to give a pale yellow oil This was dissolved in dichoromethane (100 ml) and trifluoroacetic acid (100 ml) added, the mixture was heated at reflux for 1 hour. The volatiles were removed in vacuo and the residue taken up in sodium hydroxide and washed with ethyl acetate. The aqueous layer was then acidified with concentrated hydrochloric acid and extracted with ethyl acetate, this ethyl acetate was washed with water, dried (MgSO4) and the volatiles removed in vacuo to provide the subtitle compound as a buff solid (16.4 g) which was used without further purification.

Quelle