Hydrochloric Acid → 1,5-Bis[4-(trifluoromethyl)phenyl]penta-1,4-dien-3-one

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-trifluoromethylbenzaldehyde (65.2 g; 0.369 mol), heptane (70 ml), 10% sodium hydroxide solution (15 g) and water (30 ml) is stirred under a nitrogen atmosphere and heated to 40° C. Next, a solution of acetone (10.7 g) and of bis(2-hydroxyethyl)methyloleylammonium chloride (1.6 g) in heptane (30 ml) is added dropwise over three hours at the above temperature. After the addition is completed, the mixture is stirred at 40° C. to 45° C. for two hours. After two hours, isopropyl alcohol (68 ml) and hydrochloric acid (9.4 ml; concentrated) are added and the mixture heated at reflux for 1.5 hours. The reaction mixture is then cooled to 20° C., the precipitated solid is isolated by filtration, washed with heptane (40 ml) and water to afford 56.8 g of 99.6% pure title product, mp 154° C. to 156° C. (83.0% yield).

Provenance & Evidence