Donor‐substituted distyrylpyrazines: influence of steric congestion on UV–Vis absorption and fluorescence

  • Christoph Wink
    Institut für Organische Chemie Duesbergweg 10‐14 D–55099 Mainz Germany
  • Heiner Detert
    Institut für Organische Chemie Duesbergweg 10‐14 D–55099 Mainz Germany

説明

<jats:p>Di(<jats:italic>p</jats:italic>‐aminostyryl)pyrazines with voluminous substituents on the nitrogen and in the adjacent positions were prepared via twofold aldol condensation. Absorption and emission spectra are influenced by increasing steric hindrance because the orbital overlap between nitrogen and π‐system is modulated by voluminous groups. Strong solvatochromism of the fluorescence and huge Stokes shifts result from amplified donor–acceptor interaction in the excited state. Protonation occurs at the terminal amino groups first, followed by protonation of the central pyrazine. With increasing strength of acid, absorption and emission spectra are first shifted to the blue followed by a redshift. Copyright © 2012 John Wiley & Sons, Ltd.</jats:p>

収録刊行物

被引用文献 (1)*注記

もっと見る

詳細情報 詳細情報について

問題の指摘

ページトップへ