Acetone → 1,5-Bis(2-methylphenyl)-1,4-pentadien-3-one

Participants

Reaction Steps

2-Methylbenzaldehyde (1ac, 1.45 ml, 12.5 mmol) and acetone (19, 0.46 ml, 6.3 mmol) were combined in ethanol (20 ml) and stirred for 15 min at room temperature. A solution of sodium hydroxide (2.61 g, 65.3 mmol) and water (25 ml) was added and the mixture stirred for 3 hr at room temperature. The resulting mixture was extracted into ethyl acetate, washed with saturated sodium chloride, dried over magnesium sulfate, filtered and evaporated to afford a solid. The crude solid was recrystallized from ethanol to give 0.71 g (43%) of a yellow solid: mp 98-100° C. [expected mp 94-96° C.]; 1H NMR: δ 2.47 (s, 6H), 6.98 (d, 2H, J=15.9 Hz), 7.24 (m, 6H), 7.64 (d, 2H, J=7.2 Hz), 8.03 (d, 2H, J=15.9 Hz); 13C NMR: δ 19.7, 126.1, 126.2, 126.5, 129.9, 130.7, 133.6, 137.9, 140.5, 188.5.

Provenance & Evidence