Caffeic acid phenethyl ester (CAPE): Synthesis and X-ray crystallographic analysis

The structure of caffeic acid phenethyl ester [2-propenoic acid, 3-(3, 4-di hydroxyphenyl)-, 2-phenethyl ester] (I), C17H16O4.1/2C(6)H(6), synthesized by base-catalyzed alkylation of caffeic acid salt with beta -bromoethylbenz ene in HMPA (hexamethylphosphoramide) and recrystallized from benzene, was confirmed by single crystal X-ray diffraction. The crystals are triclinic, space group P (1) over bar, Z=2, unit cell dimension a=5.8129 (9) Angstrom, b=11.122 (2) Angstrom, c= 13. 226 (2) Angstrom, alpha =97.080 (3)degrees, beta =101.467 (3)degrees, gamma =95.405 (3)degrees, V=825.4 (2) Angstrom (3 ), D-calc=1.301 g/cm(3), F(000)=342. The packing of the molecule is stabili zed by intermolecular O1H . . .O-4 (2.69 Angstrom) and O-1. . . HO2 (2.82 A ngstrom) hydrogen bonds.