反应详情

温度

0 °C

3-Hydroxy-4-pentyloxy-benzaldehyde (0.750 g., 3.6 mmol, 1 equiv. ) is dissolved in 10 mL of methylene chloride. Diisopropyl ethyl amine (0.840 g., 6.5 mmol, 1.8 equiv. ) is then added, and the mixture is cooled to 0° C. Acetyl chloride (0.340 g., 4.32 mmol, 1.2 equiv. ) dissolved in 2 mL of methylene chloride is added slowly, and the reaction is stirred at 0° C. for 20 min., followed by stirring 30 min. at room temperature. The mixture is diluted with ether, and washed twice with water, dilute HCl, then brine. The organic phase is dried (MgSO4), and evaporated. Trituration with ether affords 3-acetoxy-4-pentyloxy-benzaldehyde (0.750 g., 3.0 mmol, 83%) as a white solid: UVmax (EtOH) 232 nm (ε=17514), 276 nm (ε=12951), 208 nm (ε=10508), 314 nm (ε=10472 ); 1H NMR (300 MHz, CDCl3) δ 9.85 (s, 1H, CHO), 7.45-7.40 (m, 2H, ArH), 6.95 (d, J=8 Hz, 1H, ArH), 4.15 (t, J=7 Hz, 2H, OCH2R), 2.03 (s, 3H, CH3CO), 1.90-1.85 (m, 2H, OCH2CH2R), 1.57-1.40 (m, 4H, pentyl), 0.95 (t, J=7 Hz, 3H, RCH3); 13C NMR (75 MHz, CDCl3) δ 191.07 (C=O), 151.31, 146.17, 130.39, 124.56, 113.99, 110.85, 69.27, 28.67, 28.04, 22.38, 13.96; IR (KBr) 2950, 1750, 1680, 1600, 1580, 1510, 1230, 1250 cm-1 ; MS (DCI) m/e 251 (MH+). Anal. Calcd for C14H18O4 : C, 67.20; H, 7.20. Found: C, 66.92; H, 7.62.

1. additionis added slowly
2. stirringby stirring 30 min. at room temperature
3. washwashed twice with water, dilute HCl
4. dry with materialThe organic phase is dried (MgSO4)
5. customevaporated