反应详情

5-Isopropyl-2,4-dimethoxy-benzoic acid methyl ester (5.5 g, 23.1 mmol) and NaOH (1.38 g, 34.6 mmol) in THF (46 ml) and water (46 ml) was warmed to 50° C. overnight. The reaction was cooled and diluted with water and EtOAc. The aqueous layer was neutralised with HCl (1N, aq.). The product was extracted with EtOAc (×3) and the combined organic layers were washed with brine and dried over MgSO4. The product was filtered and evaporated to dryness to yield 5-isopropyl-2,4-dimethoxy-benzoic acid as a pale peach solid (4.7 g). 1H NMR (DMSO-d6) 12.1 (1H, br s), 7.62 (1H, s), 6.71 (1H, s), 3.95 (3H, s), 3.91 (3H, s), 3.19 (1H, sept), 1.18 (6H, d). MS: [M+H]+ 225.

1. temperatureThe reaction was cooled
2. extractionThe product was extracted with EtOAc (×3)
3. washthe combined organic layers were washed with brine
4. dry with materialdried over MgSO4
5. filtrationThe product was filtered
6. customevaporated to dryness