Hydrochloric Acid → 4-Carboxychalcone

Participants

Reaction Steps

Acetophenone (44b, 0.50 ml, 4.3 mmol) and sodium hydroxide (0.50 g, 12.5 mmol) were combined in ethanol (2 ml) and water (2 ml) and stirred for 30 min at room temperature. 4-Formylbenzoic acid (1ad, 0.71 g, 4.7 mmol) was added and the mixture stirred for 48 hr at room temperature. Water (25 ml) was added, the mixture acidified with hydrochloric acid (1 N) and the resulting precipitate was filtered and recrystallized from ethyl acetate to give 0.65 g (60%) of a white solid: mp 222-224° C. [expected mp 227-229° C.]; NMR: (DMSO) δ 7.67 (m, 4H), 7.99 (m, 4H), 8.18 (m, 3H), 13.14 (s, 1H); 13C NMR: (DMSO) δ 124.2, 128.5, 128.7, 128.8, 129.6, 132.1, 133.2, 137.3, 138.7, 142.4, 166.7, 189.0.

Provenance & Evidence