Yoriko Sonoda, Seiji Tsuzuki, Nobuyuki Tamaoki, Midori Goto
ACTA CRYSTALLOGRAPHICA SECTION C-CRYSTAL STRUCTURE COMMUNICATIONS 63 O196 - O200 0108-2701 2007/03
[Refereed][Not invited] The crystal structures of the four E, Z, E isomers of 1-(4-alkoxyphenyl)-6-(4-nitrophenyl)hexa-1,3,5-triene, namely (E,Z,E)-1-(4-methoxyphenyl)-6-(4-nitrophenyl) hexa-1,3,5-triene, C19H17NO3, (E,Z,E)-1-(4-ethoxyphenyl)-6-(4-nitrophenyl)hexa-1,3,5-triene, C20H19NO3, (E,Z,E)-1-(4-nitrophenyl)6-(4-n-propoxyphenyl)hexa-1,3,5-triene, C21H21NO3, and (E,Z,E)-1-(4-n-butoxyphenyl)-6-(4-nitrophenyl)hexa-1,3,5-triene, C22H23NO3, have been determined. Intermolecular N center dot center dot center dot O dipole interactions between the nitro groups are observed for the methoxy derivative, while for the ethoxy derivative, two adjacent molecules are linked at both ends through N center dot center dot center dot O dipole-dipole interactions between the N atom of the nitro group and the O atom of the ethoxy group to form a supramolecular ring-like structure. In the crystal structures of the n-propoxy and n-butoxy derivatives, the shortest intermolecular distances are those between the two O atoms of the alkoxy groups. Thus, the nearest two molecules form an S-shaped supramolecular dimer in these crystal structures.