Hexyl (E)-3-(3,4-dihy­droxy­phen­yl)acrylate

The title mol­ecule, C₁₅H₂₀O₄, has an E conformation about its C=C bond and is almost planar (r.m.s. deviation of all non-H atoms = 0.04 Å). The crystal structurere features O—H...O and C—H...O hydrogen bonds.

(E)-Isopentyl 3-(3,4-dihy­droxy­phen­yl)­acrylate

The title compound, C₁₄H₁₈O₄, a derivative of caffeic acid, has an E configuration about the C=C bond. The benzene ring is almost coplanar with the C=C—C(O)—O—C linker [maximum deviation = 0.050 (2) Å], making a dihedral angle of only 4.53 (2)°. In the mol­ecule, the adjacent hy­droxy groups form an O—H...O inter­action. In the crystal, mol­ecules are linked by O—H...O hydrogen bonds, generating a chain propagating in the [110] direction.