反应详情

To a solution of 3-(4-formyl-2,6-dimethyl-phenyl)-acrylic acid methyl ester (2.9 g, 13.3 mmol) in methanol (70 mL), 2 N aq. NaOH (35 mL) is added. The suspension is stirred for 30 min at rt. Methanol is evaporated and the aq. solution is extracted twice with DCM. The aq. layer is acidified with 2 N aq. HCl and extracted twice with EA. The combined EA extracts are dried over MgSO4, filtered and evaporated. The crude product is recrystallized from EA to give 3-(4-formyl-2,6-dimethyl-phenyl)-acrylic acid (2.2 g) as pale yellow crystals; LC-MS: tR=0.83 min; 1H NMR (D6-DMSO): δ 12.65 (s br, 1H), 9.92 (s, 1H), 7.66 (d, J=16.4 Hz, 1H), 7.61 (s, 2H), 6.12 (d, J=16.4 Hz, 1H), 2.35 (s, 6H).

1. customMethanol is evaporated
2. extractionthe aq. solution is extracted twice with DCM
3. extractionextracted twice with EA
4. dry with materialThe combined EA extracts are dried over MgSO4
5. filtrationfiltered
6. customevaporated
7. customThe crude product is recrystallized from EA