Hydrochloric Acid → 4-Methoxycinnamate methyl ester

Participants

Reaction Steps

p-Methoxycinnamic acid was dissolved in refluxing methanol containing a catalytic amount of hydrogen chloride to form methyl p-methoxycinnamate. The yield of purified ester was 85%, m.p. 88°-89° (lit. 90°; Dictionary of Organic Compounds, II, Sir Ian Heilbron, ed., p. 600 (1946)): λmaxCCl4 3.32, 3.38 and 3.52 (CH1 -OCH3), 5.81 (C=O), 6.1 and 10.15 (CH=CH, trans), 7.95 and 8.5-8.6 (ester)μ. The NMR (δ) supported the expected structure: 6.13-7.78 (series of multiples, aromatic and vinyl), 3.86 (--CO2CH3), and 3.78 (AR--O--CH3).

Provenance & Evidence