Isobutyraldehyde → 2-Cyclohexen-1-one, 4,4,6-trimethyl-

Participants

Reaction Steps

The procedure of example III was employed on 12 moles of isobutyraldehyde, 11 moles of methyl isopropenyl ketone and 800 ml of 0.8 M aqueous sodium hydroxide solution. After the reaction was completed the aqueous layer was removed. To the residual organic phase was added an equal volume of benzene and a catalytic amount (ca. 5 g) of p-toluenesulfonic acid. The reaction mixture was heated at reflux with concomitant removal of water via a Dean Stark trap. The usual workup and distillation afforded 897 g (59%) of the desired 4,4,6-trimethyl-2-cyclohexenone (II) with physical constants and spectral data identical with that isolated in Example III. Continued distillation afforded no material containing the 5-hydroxy-2,4,4-trimethylcyclohexanone isolated in Example III where the acid treatment step was omitted.

Provenance & Evidence