反应详情

A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), BuOH (10 mL) and toluene (15 mL) is taken in a round bottom flask and catalytic amount of AMBERLYST® 15 (0.1 g) is added to it. The mixture is refluxed for 6 hrs under Dean Stark apparatus. After completion of the reaction (observed by TLC and by GC analysis), the reaction mixture is filtered and washed with ethylacetate (5 ml×2). Concentrate the filtrate under reduced pressure and the crude product thus obtained is loaded on a neutral alumina column and eluted with diethyl ether. Butyl cinnamate (from formula I where X1═H, X2═H, X3═H, X4═H, X5═H, R═C4H9) is isolated in 94% yield. 1H-NMR (CDCl3, 300 MHz) δ7.48 (1H, d), 7.25 (2H, m), 7.11 (3H, m), 6.23 (1H, m), 3.98 (2H, t), 1.45 (2H, m), 1.19 (2H, m), 0.74 (3H, t); 13C-NMR (CDCl3, 75.4 MHz) δ166.5, 144.2, 134.4, 129.9, 127.9, 118.2, 64.0, 30.7, 19.1, 13.6.

1. customis taken in a round bottom flask
2. temperatureThe mixture is refluxed for 6 hrs under Dean Stark apparatus
3. customAfter completion of the reaction (observed by TLC and by GC analysis)
4. filtrationthe reaction mixture is filtered
5. washwashed with ethylacetate (5 ml×2)
6. concentrationConcentrate the filtrate under reduced pressure
7. customthe crude product thus obtained
8. washeluted with diethyl ether