title: Exact helical polymer synthesis by a two-point-covalent-linking protocol between C2-chiral spirobifluorene and C2- or C(s)-symmetric anthraquinone monomers.
abstract: Two types of one-handed exact helical polymers, coil- and screw-shaped polymers, were synthesized by the two-point-covalent-linking protocol using C2-chiral spirobifluorene (SBF) and C2- or C(s)-symmetric anthraquinone spacers. Central to this protocol is a new aromatic ring-forming reaction based on the stepwise reductive cyclization of bis(aryloxy group)-substituted anthraquinone derivatives. The helical structures of the polymers annulated by aromatic skeletons exhibited high thermal stability attributed to the rigid C2-chiral SBF units and the covalently two-point-connected structure.
authors.affiliation: Department of Organic and Polymeric Materials, Tokyo Institute of Technology, 2-12-1, Ookayama, Meguro-ku, Tokyo 152-8552, Japan. ttakata@polymer.titech.ac.jp.
authors.forename: Zhaozhong
authors.initials: Z
authors.lastname: Yi
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Okuda
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Koyama
authors.forename: Ryota
authors.initials: R
authors.lastname: Seto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Uchida
authors.forename: Hiromitsu
authors.initials: H
authors.lastname: Sogawa
authors.forename: Shigeki
authors.initials: S
authors.lastname: Kuwata
authors.forename: Toshikazu
authors.initials: T
authors.lastname: Takata