(E)-1-Methyl-4-[2-(1-naphthyl)vinyl]pyridinium 4-bromobenzenesulfonateThis paper is dedicated to the late Her Royal Highness Princess Galyani Vadhana Krom Luang Naradhiwas Rajanagarindra for her patronage of Science in Thailand.

• Main Authors: Hoong-Kun Fun, Kullapa Chanawanno, Suchada Chantrapromma
• Format: Article
• Language: English
• Published: International Union of Crystallography 2009-05-01
• Series: Acta Crystallographica Section E
• Online Access: http://scripts.iucr.org/cgi-bin/paper?S1600536809014974

In the title compound, C18H16N+·C6H4BrO3S−, the cation exists in the E configuration and the whole molecule of the cation is disordered with a refined site-occupancy ratio of 0.733 (1):0.267 (1). The naphthalene system is not planar, the interplanar angle between the two aromatic rings being 5.0 (5)° for the major component and 5.7 (10)° for the minor component. The cation is twisted with dihedral angles between the pyridinium ring and the two aromatic rings of the naphthalene system of 56.3 (5) and 51.4 (5)° (for the major component) and 52.2 (11) and 53.4 (11)° (for the minor component). The pyridinium ring and the benzene ring of the anion are inclined to each other at interplanar angles of 85.0 (4) and 71.5 (9)° for the major and minor components, respectively. In the crystal packing, the cations and anions are alternately arranged with the cations stacked in an antiparallel manner along the c axis and the anions linked together into chains along the same direction. The cations are linked to the anions into chains along [102] by weak C—H...O interactions. The crystal structure is further stabilized by C—H...π interactions and π–π contacts, with Cg...Cg distances of 3.502 (9) and 3.698 (6) Å. A short Br...O contact [3.029 (4) Å] is also present.