Réaction #94083

Équation de réaction

methyl vinyl ketone

hydroquinone

acetic

sodium methylate

→

2,3,6-trimethyl-2-cyclohexen-1-one

4-methyl-3-ethyl-2-cyclohexen-1-one

Solvants

water

diethyl ketone

Conditions de réaction

Traitement

1. 1
   Températureunder reflux
2. 2
   TempératureThe whole is then heated for another two hours
3. 3
   Températureunder reflux
4. 4
   AutreThe mixture obtained
5. 5
   Filtrationfiltered
6. 6
   workup.DISTILLATIONExcess diethyl ketone and the water present are distilled off

Mode opératoire

A mixture of 70 g of methyl vinyl ketone, 10 g of water and 0.1 g of hydroquinone is dripped in the course of one hour into a mixture of 400 g of diethyl ketone and 10 g of a 30% by weight methanolic solution of sodium methylate which is boiling under reflux. The whole is then heated for another two hours under reflux. The mixture obtained is neutralized with glacial acetic and then filtered. Excess diethyl ketone and the water present are distilled off and the residue is fractionated in vacuo. 81 g of 2,3,6-trimethyl-2-cyclohexen-1-one having a boiling point of 89° C. at 12 mm Hg and 9 g of 4-methyl-3-ethyl-2-cyclohexen-1-one having a boiling point of 102° C. at 12 mm Hg are obtained. The total yield of cyclohexenone is 65% with reference to methyl vinyl ketone.

Source