반응 #54958

반응 방정식

acetyl chloride

methyl 2-(4-methoxyphenyl)propionate

boron trichloride

→

oil

Methyl 2-(3-acetyl-4-hydroxyphenyl)propionate

용매

dichloromethane

반응 조건

후처리

1. 1
   온도cooled in an ice/salt-bath, at a rate sufficient
2. 2
   온도to maintain the temperature between -10° C. and -5° C
3. 3
   온도to maintain the temperature below 0° C
4. 4
   workup.ADDITIONwas added
5. 5
   workup.STIRRINGStirring
6. 6
   workup.WAITwas continued for 1/2 hour at +3° C.
7. 7
   workup.ADDITIONbefore pouring on
8. 8
   기타to crushed ice/concentrated hydrochloric acid
9. 9
   기타separating the two phases
10. 10
    추출The aqueous phase was extracted with ether (3x)
11. 11
    세척the combined organic extracts were washed with saturated sodium bicarbonate solution, saturated brine solution
12. 12
    건조dried over anhydrous magnesium sulphate
13. 13
    기타Evaporation of the solvent
14. 14
    기타yielded the crude product as a pale yellow oil
15. 15
    workup.DISTILLATIONVacuum distillation

실험 절차

Titanium tetrachloride (82.3 mls) was added dropwise to a stirred solution of methyl 2-(4-methoxyphenyl)propionate (25 g) in dry dichloromethane (250 mls), cooled in an ice/salt-bath, at a rate sufficient to maintain the temperature between -10° C. and -5° C. The mixture was stirred for 10 minutes and acetyl chloride (10 g) was added dropwise at a rate sufficient to maintain the temperature below 0° C. The solution was stirred at -5° C. for 11/2 hours when boron trichloride (15 mls) was added. Stirring was continued for 1/2 hour at +3° C. before pouring on to crushed ice/concentrated hydrochloric acid and separating the two phases. The aqueous phase was extracted with ether (3x) and the combined organic extracts were washed with saturated sodium bicarbonate solution, saturated brine solution, and dried over anhydrous magnesium sulphate. Evaporation of the solvent yielded the crude product as a pale yellow oil. Vacuum distillation furnished a pale yellow oil bp 120°-125° C./0.15 mm (16.2 g; 59%)

출처