title: Planar-chiral through-space conjugated oligomers: synthesis and characterization of chiroptical properties.
abstract: Optically active through-space conjugated oligomers, namely, a dimer, trimer, tetramer, and cyclic trimer, consisting of a planar-chiral [2.2]paracyclophane skeleton were synthesized. In the ground state, observed similarities in the chiroptical properties of the oligomers were attributed to the equivalent orientations of two adjacent chromophores. In the excited state, the oligomers were folded into a form analogous to a one-handed helix by photoexcitation. All the compounds in dispersed solution exhibited intense circularly polarized luminescence with relatively large anisotropy factors on the order of 10(-3).
authors.affiliation: Department of Polymer Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510 (Japan), Fax: (+81) 75-383-2607. ymo@chujo.synchem.kyoto-u.ac.jp.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Morisaki
authors.forename: Kenichi
authors.initials: K
authors.lastname: Inoshita
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Chujo
keywords: circular dichroism; cyclophanes; higher-ordered structure; luminescence; planar chirality