3-Phenylprop-2-Enal → Cinnamic Acid Isopropyl Ester

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.

1. customis taken in a round bottom flask
2. additioncatalytic amount of silica gel (0.1 g) is added to it
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

ORD record

ord-1c1b94d5de364e8f806bcfb2b478fa2f

Source dataset

uspto-grants-2010_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07741508B2