title: Crystal structures of three co-crystals of 1,2-bis-(pyridin-4-yl)ethane with 4-alk-oxy-benzoic acids: 4-eth-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1), 4-n-propoxybenzoic acid-1,2-bis(pyridin-4-yl)ethane (2/1) and 4-n-but-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1).
abstract: The crystal structures of three hydrogen-bonded co-crystals of 4-alk-oxy-benzoic acid-1,2-bis-(pyridin-4-yl)ethane (2/1), namely, 2C9H10O3·C12H12N2, (I), 2C10H12O3·C12H12N2, (II), and 2C11H14O3·C12H12N2, (III), have been determined at 93, 290 and 93 K, respectively. In (I), the asymmetric unit consists of one 4-eth-oxy-benzoic acid mol-ecule and one half-mol-ecule of 1,2-bis-(pyridin-4-yl)ethane, which lies on an inversion centre. In (II) and (III), the asymmetric units each comprise two crystallographically independent 4-alk-oxy-benzoic acid mol-ecules and one 1,2-bis-(pyridin-4-yl)ethane mol-ecule. In each crystal, the two components are linked by O-H⋯N hydrogen bonds, forming a linear hydrogen-bonded 2:1unit of the acid and the base. Similar to the structure of 2:1 unit of (I), the units of (II) and (III) adopt nearly pseudo-inversion symmetry. The 2:1 units of (I), (II) and (III) are linked via C-H⋯O hydrogen bonds, forming tape structures.
authors.affiliation: Department of Chemistry, Faculty of Science, Okayama University, Okayama 700-8530, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Tabuchi
authors.affiliation: Department of Chemistry, Faculty of Science, Okayama University, Okayama 700-8530, Japan.
authors.forename: Kazuma
authors.initials: K
authors.lastname: Gotoh
authors.affiliation: Department of Chemistry, Faculty of Science, Okayama University, Okayama 700-8530, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Ishida
keywords: 1,2-bis­(pyridin-4-yl)ethane; 4-alk­oxy­benzoic acid; crystal structure; hydrogen-bonded liquid crystal