3-Phenylprop-2-Enal → Cinnamic Acid Isopropyl Ester
Reaktionsgleichung
[CH:1](=[O:10])[CH:2]=[CH:3][C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1.[CH:11]([OH:14])([CH3:13])[CH3:12]>>[C:1]([O:14][CH:11]([CH3:13])[CH3:12])(=[O:10])[CH:2]=[CH:3][C:4]1[CH:9]=[CH:8][CH:7]=[CH:6][CH:5]=1Komponenten
3
Versuchsvorschrift
A homogeneous mixture containing cinnamaldehyde (7.5 mmol), Chloronil (22.5 mmol), isopropanol (10 mL) is taken in a round bottom flask and catalytic amount of silica gel (0.1 g) is added to it. The mixture is stirred for 20 hrs at room temperature. 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. Isopropyl cinnamate (from formula I where X1═H, X2═H, X3═H, X4═H, X5═H, R═C3H8) is isolated in 49% yield. 1H-NMR (CDCl3, 300 MHz) δ7.59 (1H, d, J=16.55 Hz), 7.41 (2H, m), 7.27 (3H, m), 6.34 (1H, d, J=16.55 Hz), 5.07 (1H, m), 1.18 (6H, d); 13C-NMR (CDCl3, 75.4 MHz) δ166.4, 144.3, 134.5, 130.1, 128.6, 128.0, 118.8, 67.7, 21.9.