반응 #2028869

반응 방정식

HCl

Ethyl difluoroacetate

sodium methoxide

methanol

4′-chloroacetophenone

→

yellow solid

수율 99.5%

4,4-difluoro-1-[4-(chloro)phenyl]-butane-1,3-dione

수율 99.5%

용매

ether

diethyl ether

diethyl ether

반응 조건

후처리

1. 1
   workup.ADDITIONadded to the reaction dropwise over 5 minutes
2. 2
   workup.ADDITIONwere added
3. 3
   기타The organic layer was collected
4. 4
   세척washed with brine (250 mL)
5. 5
   건조dried over MgSO4
6. 6
   여과filtered
7. 7
   농축concentrated in vacuo

실험 절차

Ethyl difluoroacetate (24.82 g, 200 mmol) was placed in a 500 mL three-necked round bottom flash, and dissolved in diethyl ether (200 mL). To the stirred solution was added 25% sodium methoxide in methanol (48 mL, 210 mmol) via an addition funnel over a 2 minute period. Next, 4′-chloroacetophenone (25.94 g, 200 mmol) was dissolved in diethyl ether (50 mL), and added to the reaction dropwise over 5 minutes. After stirring overnight (18 hours), 1N HCl (250 mL) and ether (250 mL) were added. The organic layer was collected, washed with brine (250 mL), dried over MgSO4, filtered, and concentrated in vacuo to give 46.3 g of a yellow solid. The solid was recrystallized from methylene chloride and iso-octane to give 31.96 g (69%) of the dione: mp 65°-66.5° C.

출처