反应详情

A mixture of 3-hydroxy-4-ethoxybenzaldehyde (0.350 g, 2.5 mmol), 3,4,5-trimethoxyacetophenone (0.443 mg, 2.5 mmol) and 50% w/v of aqueous sodium hydroxide (3.37 ml, 0.042 mol) in methanol (5 ml) at room temperature for 18 h. An orange solid was isolated by filtration, dissolved in ethyl acetate which was subsequently dried over MgSO4 and reduced in vacuo. Purification by column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate) yielded 0.126 g (16.7%) of a yellow solid. 1H-NMR (CDCl3) δ 7.7 (d, 1H), 7.3 (m, 4H), 7.1 (dd, 1H), 6.9 (d, 1H), 5.75 (s, 1H), 4.2 (q, 2H), 3.95 (s×2, 9H), 1.5 (t, 3H). 13C-NMR (CDCl3) δ 190.0, 153.1, 150.0, 146.0, 133.7, 128.4. Mass Spectrum m/e (M+1) 359. Anal. Calcd. for C20H22O6: C, 67.03; H, 6.19. Found C, 66.74; H, 6.33.

1. customAn orange solid was isolated by filtration
2. dry with materialwas subsequently dried over MgSO4
3. customPurification by column chromatography (SiO2, petroleum:ether (40:60 v/v) with an increasing gradient of ethyl acetate)