Mesityl oxide


Mesityl oxide is a α,β-unsaturated ketone with the formula CH3CCH=C2. This compound is a colorless, volatile liquid with a honey-like odor.

Synthesis

It is prepared by the aldol condensation of acetone to give diacetone alcohol, which readily dehydrates to give this compound.
Phorone and isophorone may be formed under the same conditions. Isophorone originates via a Michael addition:
Phorone is formed by continued aldol condensation:

Uses

Mesityl oxide is used as a solvent and in the production of methyl isobutyl ketone by hydrogenation:
Complete hydrogenation gives 4-methyl-2-pentanol.