title: Stealth fast photoswitching of negative photochromic naphthalene-bridged phenoxyl-imidazolyl radical complexes.
abstract: Naphthalene-bridged phenoxyl-imidazolyl radical complex (Np-PIC) is a novel fast switchable negative photochromic compound, which shows the thermal back reaction in the millisecond time scale. Upon UV light irradiation, Np-PIC shows the hypochromic effect in the UVA region due to there being less conjugation in the transient isomer. By replacing the phenoxyl unit with a naphthoxyl unit, the molecular structure has an asymmetric carbon, leading to fast chiroptical switching. This simple molecular design will be a good candidate for the future development of negative photochromic compounds.
authors.affiliation: Department of Chemistry, School of Science and Engineering, Aoyama Gakuin University, 5-10-1 Fuchinobe, Chuo-ku, Sagamihara, Kanagawa 252-5258, Japan. jiro_abe@chem.aoyama.ac.jp.
authors.forename: Katsuya
authors.initials: K
authors.lastname: Mutoh
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: Yasukazu
authors.initials: Y
authors.lastname: Hirao
authors.forename: Takashi
authors.initials: T
authors.lastname: Kubo
authors.forename: Jiro
authors.initials: J
authors.lastname: Abe