title: Host-Guest Complexation of Perethylated Pillar[5]arene with Alkanes in the Crystal State.
abstract: Activated perethylated pillar[5]arene crystals show an unexpected alkane-shape- and -length-selective gate-opening behavior. Activated crystals were obtained upon removing solvents from perethylated pillar[5]arene crystals by heating. The activated crystals could quantitatively take up n-alkanes with carbon chains containing more than five carbon atoms as a consequence of their gate-opening pressure. As the chain length of the n-alkanes increased, the gate pressure decreased. A transformation into a herringbone structure was induced when n-hexane was used as a guest. By contrast, cyclic and branched alkanes were not taken up and could not induce a crystal transformation because they were too large to fit in the cavities of the pillar[5]arene. Alkane-shape-selective molecular recognition of pillar[5]arenes in the solution state was translated into the vapor/crystal state.
authors.affiliation: Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan). ogoshi@se.kanazawa-u.ac.jp.|PRESTO, the Japan Science and Technology Agency (JST), 4-1-8 Honcho, Kawaguchi 332-0012 (Japan) (Japan). ogoshi@se.kanazawa-u.ac.jp.
authors.forename: Tomoki
authors.initials: T
authors.lastname: Ogoshi
authors.affiliation: Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan).
authors.forename: Ryuta
authors.initials: R
authors.lastname: Sueto
authors.affiliation: Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan).
authors.forename: Kumiko
authors.initials: K
authors.lastname: Yoshikoshi
authors.affiliation: Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan).
authors.forename: Yoko
authors.initials: Y
authors.lastname: Sakata
authors.affiliation: Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan). akine@se.kanazawa-u.ac.jp.
authors.forename: Shigehisa
authors.initials: S
authors.lastname: Akine
authors.affiliation: Graduate School of Natural Science and Technology, Kanazawa University, Kakuma-machi, Kanazawa 920-1192 (Japan).
authors.forename: Tada-aki
authors.initials: TA
authors.lastname: Yamagishi
keywords: alkanes; crystals; host-guest chemistry; macrocyclic compound; pillar[n]arenes