Title of article :
The crystal structure of the triclinic polymorph of 1,4-bis([2,2′:6′,2′′-terpyridin]-4′-yl)benzene
Author/Authors :
Sedykh, Alexander E. Institute of Inorganic and Analytical Chemistry - Justus-Liebig-Universität Giessen, Germany , Kurth, Dirk G. Lehrstuhl für Chemische Technologie der Materialsynthese - Julius-Maximilians-University Würzburg,Germany , Müller-Buschbaum, Klaus Institute of Inorganic and Analytical Chemistry - Justus-Liebig-Universität Giessen, Germany
Abstract :
The title triclinic polymorph (Form I) of 1,4-bis([2,2′:6′,2′′-terpyridin]-4′-yl)benzene, C36H24N6, was formed in the presence of the Lewis acid yttrium trichloride in an attempt to obtain a coordination compound. The crystal structure of the orthorhombic polymorph (Form II), has been described previously [Fernandes et al. (2010[Fernandes, J. A., Almeida Paz, F. A., Lima, P. P., Alves, S. Jr & Carlos, L. D. (2010). Acta Cryst. E66, o3241-o3242.]). Acta Cryst. E66, o3241–o3242]. The asymmetric unit of Form I consists of half a molecule, the whole molecule being generated by inversion symmetry with the central benzene ring being located about a crystallographic centre of symmetry. The side pyridine rings of the 2,2′:6′,2′′-terpyridine (terpy) unit are rotated slightly with respect to the central pyridine ring, with dihedral angles of 8.91 (8) and 10.41 (8)°. Opposite central pyridine rings are coplanar by symmetry, and the angle between them and the central benzene ring is 49.98 (8)°. The N atoms of the pyridine rings inside the terpy entities, N⋯N⋯N, lie in trans–trans positions. In the crystal, molecules are linked by C—H⋯π and offset π–π interactions [intercentroid distances are 3.6421 (16) and 3.7813 (16) Å], forming a three-dimensional structure.
Keywords :
crystal structure , terpyridine , C—H⋯π interactions , offset π–π interactions