Crystal structure of (E)-4-{2-[4-(all­yloxy)phen­yl]diazen­yl}benzoic acid

The title compound has an E conformation about the azo­benzene linkage and the benzene rings are almost coplanar to one another [dihedral angle = 1.36 (7)°]. In the crystal, a combination of O—H...O and C—H...O hydrogen bonds and C—H...π inter­actions leads to the formation of slabs parallel to (001).

6-(Hex-5-en­yloxy)naphthalene-2-carb­oxy­lic acid

The asymmetric unit of the title compound, C₁₇H₁₈O₃, comprises three independent mol­ecules with similar geometries. In each mol­ecule, the carbonyl group is twisted away from the napthalene ring system, making dihedral angles of 1.0 (2), 1.05 (19)° and 1.5 (2)°. The butene group in all three mol­ecules are disordered over two sets of sites, with a refined occupancy ratio of 0.664 (6):0.336 (6). In the crystal, mol­ecules are oriented with respect to their carbonyl groups, forming head-to-head dimers via O—H...O hydrogen bonds. Adjacent dimers are further inter­connected by C—H...O hydrogen bonds into chains along the a-axis direction. The crystal structure is further stabilized by weak C—H...π inter­actions.