title: Preparation of a cyclic polyphenylene array for a zigzag-type carbon nanotube segment.
abstract: Preparation of cyclic polyphenylene array 2, which corresponds to a complete carbon array of a zigzag-type CNT segment with (18,0)-structure, has been established by a Diels-Alder reaction of cyclic biphenylylene-acetylene derivative 1 with tetraphenylcyclopentadienone. The reaction of 2 with excess FeCl3 realized a presumed cyclodehydrogenation reaction and elimination of the alkyl chains that were introduced as a measure to counter the low solubility problem, but this resulted in the formation of a complicated mixture that included the mass region of a presumed zigzag-type CNT segment with (18,0)-structure. The rather efficient blue emission of cyclic compounds 1 and 2 was discussed utilizing fluorescence (FL) quantum efficiencies (Φ(FL)) and lifetimes (τ(FL)) in their crystalline state along with those in dichloromethane solution. Thermal analyses of these compounds revealed their characteristic phase transition behavior. The synthesis of a novel cyclic polyphenylene array by utilizing a Diels-Alder reaction of cyclic phenylene-acetylene compounds with tetraphenylcyclopentadienone should afford an attractive pathway to a novel belt-shaped CNT segment.
authors.affiliation: †Graduate School of Science and Technology, Hirosaki University, Hirosaki 036-8561, Japan.
authors.forename: Ryuta
authors.initials: R
authors.lastname: Sekiguchi
authors.affiliation: †Graduate School of Science and Technology, Hirosaki University, Hirosaki 036-8561, Japan.
authors.forename: Kei
authors.initials: K
authors.lastname: Takahashi
authors.affiliation: †Graduate School of Science and Technology, Hirosaki University, Hirosaki 036-8561, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Kawakami
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sakai
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ikeda
authors.affiliation: ∥Smart Material Science and Technology, Interdisciplinary Graduate School of Science and Technology, Shinshu University, Ueda 386-8567, Japan.
authors.forename: Aya
authors.initials: A
authors.lastname: Ishikawa
authors.affiliation: ∥Smart Material Science and Technology, Interdisciplinary Graduate School of Science and Technology, Shinshu University, Ueda 386-8567, Japan.
authors.forename: Kazuchika
authors.initials: K
authors.lastname: Ohta
authors.affiliation: †Graduate School of Science and Technology, Hirosaki University, Hirosaki 036-8561, Japan.
authors.forename: Shunji
authors.initials: S
authors.lastname: Ito