title: Solid-state circularly polarised luminescence of atropisomeric fluorophores embedded in achiral myo-inositol-containing polyurethanes.
abstract: We investigated the ground- and photoexcited-state chiralities of two chiral fluorophores with a rigid framework embedded in two achiral polyurethanes as the solid matrices. As the fluorophores, we used two pairs of atropisomeric binaphthyl derivatives, (R)-(−)-1,1′-binaphthyl-2,2′-diyl hydrogen phosphate [(R)-1a] and (R)-(−)-(3,5-dioxa-4-phosphacyclohepta-[2,1-a:3,4-a′]dinaphthalen-4-yl)-dimethylamine [(R)-1b], and for comparison, their optical antipodes (S)-1a and (S)-1b. As the solid matrices, we used two soluble achiral polyurethanes (2a and 2b) derived from the naturally occurring myo-inositol as the building block, because these polymers had a high glass transition temperature of ~150 °C. The chiral fluorophores in the polyurethanes emitted circularly polarised luminescence with a high circular anisotropy of ~0.6–1.5 × 10(-3). Regardless of the matrix, (R)- and (S)-1a had nearly mirror-image chiroptical properties in the ground and photoexcited states, as did (R)- and (S)-1b.
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Engineering, Kinki University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan. y-imai@apch.kindai.ac.jp.
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Amako
authors.forename: Kazuki
authors.initials: K
authors.lastname: Nakabayashi
authors.forename: Atsushi
authors.initials: A
authors.lastname: Sudo
authors.forename: Michiya
authors.initials: M
authors.lastname: Fujiki
authors.forename: Yoshitane
authors.initials: Y
authors.lastname: Imai