تفاعل #216385

معادلة التفاعل

HCl

Ethyl difluoroacetate

sodium methoxide

methanol

4'-chloroacetophenone

→

yellow solid

المردود 99.5%

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

المردود 99.5%

المذيبات

ether

diethyl ether

diethyl ether

ظروف التفاعل

المعالجة

1. 1
   workup.ADDITIONadded to the reaction dropwise over 5 minutes
2. 2
   workup.ADDITIONwere added
3. 3
   أخرىThe organic layer was collected
4. 4
   غسيلwashed with brine (250 mL)
5. 5
   تجفيفdried over MgSO4
6. 6
   ترشيحfiltered
7. 7
   تركيزconcentrated in vacuo

الإجراء التجريبي

Ethyl difluoroacetate (24.82 g, 200 mmol) was placed in a 500 mL three-necked round bottom flask, and dissolved in diethyl ether (200 mL). To the stirred solution was added 25 weight % 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.

المصدر