title: Single oxygen generation sensitized by spiro(dipyridinogermole)(dithienogermole)s.
abstract: Three spiro(dipyridinogermole)(dithienogermole) derivatives (1-3), including newly prepared spiro(dipyridinogermole)[di(2-pyridyl)dithienogermole] (3), were examined as photosensitizers for singlet oxygen (1O2) generation in dichloromethane-methanol. Irradiation of their air-saturated solutions led to the generation of1O2, which was readily trapped by well-known scavengers, dihydronaphthoquinone (DHN) and diphenylisobenzofuran (DPBF). Spiro(dipyridinogermole)[bis(n-hexylbithiophenyl)dithienogermole] (2) showed the best performance with a first-order rate constant that was higher than that of tetraphenylporphyrin (TPP), an efficient photosensitizer for1O2generation. This is ascribable to the efficient intersystem crossing characteristic of the dipyridinogermole unit. The quantum yield of1O2generation was φΔ= 0.72 for 2, relative to that for rose bengal (RB) in methanol as reference (φΔ= 0.8).
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan. jo@hiroshima-u.ac.jp.
authors.forename: J
authors.initials: J
authors.lastname: Ohshita
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan. jo@hiroshima-u.ac.jp.
authors.forename: Yuya
authors.initials: Y
authors.lastname: Hayashi
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan. jo@hiroshima-u.ac.jp.
authors.forename: Kazuya
authors.initials: K
authors.lastname: Murakami
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan. jo@hiroshima-u.ac.jp.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Enoki
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan. jo@hiroshima-u.ac.jp.
authors.forename: Yousuke
authors.initials: Y
authors.lastname: Ooyama