Reaktion #55326

Reaktionsgleichung

ether

keto-ester

diethyl-2-p-ethoxyphenyl-oxaloacetate

potassium carbonate

→

ethyl-2-(p-ethoxyphenyl)acrylate

Lösungsmittel

formaldehyde

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added dropwise
2. 2
   workup.ADDITIONwas added to the stirred suspension
3. 3
   workup.DISSOLUTIONto dissolve the gummy precipitate which
4. 4
   Sonstigeformed and after an additional 15 minutes
5. 5
   Sonstige(after about 2 hours)
6. 6
   Extraktionwas extracted with additional ether
7. 7
   Waschenthe combined ether extracts were washed with water
8. 8
   Sonstigeevaporated
9. 9
   Trocknenafter drying with Na2SO4

Vorschrift

The keto-ester III (143.8 g) was stirred in dilute formaldehyde solution (62 ml 37% formaldehyde+water 220 ml) and to the suspension potassium carbonate solution (54.5 g, in water 280 ml) was added dropwise. At the end of the addition, ether was added to the stirred suspension to dissolve the gummy precipitate which formed and after an additional 15 minutes, gas evolution commenced. When this gas evolution ceased (after about 2 hours) the reaction mixture was extracted with additional ether and the combined ether extracts were washed with water and evaporated after drying with Na2SO4. The yield of the ethyl-2-(p-ethoxyphenyl)acrylate (II) (isolated as a yellow oil) was 97.8 g (79.8%).

Quelle