title: Synthesis, Structure, and Photophysical/Chiroptical Properties of Benzopicene-Based π-Conjugated Molecules.
abstract: The convenient synthesis of substituted benzopicenes and azabenzopicenes has been achieved by the cationic rhodium(I)/H8-BINAP or BINAP complex-catalyzed [2+2+2] cycloaddition under mild conditions. This method was applied to the synthesis of benzopicene-based long ladder and helical molecules. The X-ray crystal structure analysis revealed that the benzopicene-based helical molecule is highly distorted and the average distance of overlapped rings is markedly shorter than that in the triphenylene-based helical molecule. Photophysical and chiroptical properties of these benzopicene and azabenzopicene derivatives have also been examined. With respect to photophysical properties, substituted benzopicenes and azabenzopicenes showed red shifts of absorption and emission maxima compared with the corresponding triphenylenes and azatriphenylenes. With respect to chiroptical properties, the CPL spectra of the benzopicene-based helical molecule showed two opposite peaks, and thus the value of the CPL was smaller than that of the triphenylene-based helical molecule presumably due to the presence of two chiral fluorophores.
authors.affiliation: Department of Chemical Science and Engineering, and ‡Department of Chemistry, Tokyo Institute of Technology , O-okayama, Meguro-ku, Tokyo 152-8550, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Murayama
authors.affiliation: Department of Chemical Science and Engineering, and ‡Department of Chemistry, Tokyo Institute of Technology , O-okayama, Meguro-ku, Tokyo 152-8550, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Shibata
authors.affiliation: Department of Chemical Science and Engineering, and ‡Department of Chemistry, Tokyo Institute of Technology , O-okayama, Meguro-ku, Tokyo 152-8550, Japan.
authors.forename: Haruki
authors.initials: H
authors.lastname: Sugiyama
authors.affiliation: Department of Chemical Science and Engineering, and ‡Department of Chemistry, Tokyo Institute of Technology , O-okayama, Meguro-ku, Tokyo 152-8550, Japan.
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Uekusa
authors.affiliation: Department of Chemical Science and Engineering, and ‡Department of Chemistry, Tokyo Institute of Technology , O-okayama, Meguro-ku, Tokyo 152-8550, Japan.
authors.forename: Ken
authors.identifier: 0000-0003-0534-7559
authors.initials: K
authors.lastname: Tanaka