title: Liquid crystal and crystal structure of octahomotetraoxacalix[4]arenes.
abstract: Octahomotetraoxacalix[4]arenes bearing long alkyl chains on their lower rim were prepared. Ester 4a existed in a 1,2-alternate conformation in its crystal structure, which was examined by single-crystal X-ray diffraction analysis. To prepare liquid crystalline materials possessing calixarene moieties by self-assembling, carboxylic acid derivatives 5 were synthesized. Among them, 5c, the octadecyloxy derivative, showed smectic liquid crystal phase. Homooxacalixarenes 5 also formed liquid crystal phases with longer layer distances when two equivalent moles of 1,2-ethylenediamine were added as a linker. These phases were investigated with X-ray diffraction, differential scanning calorimetry, and polarized optical microscopy.
authors.affiliation: Department of Applied Chemistry and Biotechnology, Faculty of Engineering, Chiba University, 1-33, Yayoi-cho, Inage-ku, Chiba 263-8522, Japan. kohmoto@faculty.chiba-u.jp
authors.forename: Shigeo
authors.initials: S
authors.lastname: Kohmoto
authors.forename: Yasunobu
authors.initials: Y
authors.lastname: Someya
authors.forename: Hyuma
authors.initials: H
authors.lastname: Masu
authors.forename: Kentaro
authors.initials: K
authors.lastname: Yamaguchi
authors.forename: Keiki
authors.initials: K
authors.lastname: Kishikawa
mesh_terms: D047250:Calixarenes / Q000737:chemistry*; D002152:Calorimetry, Differential Scanning; D002264:Carboxylic Acids; D003460:Crystallization; D050866:Liquid Crystals; D008859:Microscopy, Polarization; D015394:Molecular Structure; D010636:Phenols / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D002264:Carboxylic Acids; D010636:Phenols; C121325:calix(4)arene; D047250:Calixarenes