title: 4,4'-[p-Phenyl-enebis(-oxy)]dibutanoic acid.
abstract: The complete mol-ecule of the title compound, C(14)H(18)O(6), has a center of inversion at the centroid of the benzene ring and the asymmetric unit contains one half-mol-ecule. The conformation of the side chain is anti [C-C-C-C = -171.40 (17)°]. In the crystal, pairs of head-to-head carb-oxy-lic acid O-H⋯O hydrogen bonds link the mol-ecules into infinite zigzag chains propagating along [130]. Weak C-H⋯π inter-actions between adjacent chains expand the structure into a layered network in the ac plane.
authors: Department of Chemistry, School of Science, Beijing Jiaotong University, No. 3 Shang Yuan Cun Road, HaiDian District 100044,  People's Republic of China.
authors: Zhi
authors: Z
authors: Li