3-Phenylprop-2-Enal → 2-Methoxyethyl cinnamate

Beteiligte Stoffe

Reaktionsschritte

A homogeneous mixture containing cinnamaldehyde (7.5 mmol), DDQ (11.3 mmol), 2-methoxyethanol (25 mL) and toluene (10 mL) is taken in a round bottom flask and catalytic amount of basic alumina (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. 2-Methoxyethyl cinnamate (from formula I where X1═H, X2═H, X3═H, X4═H, X5═H, R═C3H7O) is isolated in 93% yield. 1H-NMR (CDCl3, 300 MHz) δ7.51 (1H, d, J=16.55 Hz), 7.28 (2H, m), 7.15 (3H, m), 6.28 (1H, d, J=16.55 Hz), 4.16 (2H, t), 3.44 (2H, t), 3.18 (3H, s); 13C-NMR (CDCl3, 75.4 MHz) δ166.6, 144.8, 134.3, 130.2, 128.8, 117.8, 70.4, 63.4, 58.7.

Herkunft & Nachweise