反应详情

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.

1. stirringthe mixture stirred for 3 hr at room temperature
2. extractionThe resulting mixture was extracted into ethyl acetate
3. washwashed with saturated sodium chloride
4. dry with materialdried over magnesium sulfate
5. filtrationfiltered
6. customevaporated
7. customto afford a solid
8. customThe crude solid was recrystallized from ethanol