Hydrochloric Acid → 4-Methoxy cinnamic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 2.34 g (10 mmol) of p-iodoanisole, 0.756 g (10.5 mmol) of acrylic acid, 0.803 g (11 mmol) of diethylamine and 16 mg of palladium on charcoal in 4 ml of dimethylformamide is stirred at 140° C. for 4 hours. Subsequently, the mixture is worked up by adding diethyl ether and 2N hydrochloric acid, washing the separated organic phase with water and subsequently drying over anhydrous sodium sulphate, concentrating the organic phase under reduced pressure and recrystallizing the solid residue from ethanol. In this manner there is obtained p-methoxycinnamic acid in 65% yield. M.p. 170° C. (no depression upon mixing with a pure sample of this acid); 1H-NMR (CDCl3, 200 MHz): 3.85 ppm (s, 3H), 6.33 ppm (d, 15.5 Hz, 1H), 6.68-6.97 ppm (duplettoid, m 1H), 7.47-7.56 ppm (dupletteid m, 1H), 7.75 ppm (d, 15.5 Hz, 1H).

Provenance & Evidence