2560. p-Coumaric Acid

Nomenclature

CAS number: 7400-08-0
3-(4-Hydroxyphenyl)-2-propenoic acid; p-hydroxycinnamic acid; β-[4-hydroxyphenyl]acrylic acid.
C9H8O3; mol wt 164.16.
C 65.85%, H 4.91%, O 29.24%.

Description and references

Isoln: Hlasiwetz, Ann. 136, 31 (1865); Bamberger, Monatsh. Chem. 12, 459 (1891). Prepn: Eigel, Ber. 20, 2528 (1887); Konek, Pacsu, Ber. 51, 856 (1918). uv data: Wheeler, Covarrubias, J. Org. Chem. 28, 2015 (1963).

Chemical structure

Properties

Needles, mp 210-213° (reported in early lit as 206°). Crystallizes in anhydrous form from conc hot aq soln, but as monohydrate from dil aq soln on slow cooling. Slightly sol in cold water; sol in hot water and alc, ether. Practically insol in benzene and ligroin. uv max (95% ethanol): 223, 286 nm (ε 14450, 19000).