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室温溶液における興奮状態の分子内チオール陽子の移転に関する章

  • 0Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan (R.O.C.).
Journal of the American Chemical Society +

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2021年8月6日

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2021年8月6日

PubMedで要約を見る

まとめ

この要約は機械生成です。

研究者は初めて溶液中のチオール陽子の興奮状態内陽子移転 (ESIPT) を実験的に観察した. 硫黄を含むESIPT反応の新たな経路を明らかにした.

科学分野

  • 写真化学
  • 超分子化学
  • 有機化学

背景

  • 興奮状態のプロトン内移転 (ESIPT) は重要な光物理学的プロセスです.
  • ESIPTは通常,O-HまたはN-Hの転送を含みますが,S-Hの転送はあまり調査されていません.
  • ESIPTメカニズムを理解することは,新しい光反応材料の設計に不可欠です.

研究 の 目的

  • ティオール陽子を含む興奮状態の分子内陽子移転 (ESIPT) を実験的に実証する.
  • 3-チオルフラボン誘導体,特に3NTFの光物理学的性質を調査する.
  • 室温での硫黄を含む化合物のESIPTのメカニズムを解明する.

主な方法

  • 3NTFとそのメチル化同位体3MeNTFを含む3チオルフラボン誘導体の合成
  • サイクロヘクサンの安定状態の吸収と放出スペクトロスコーピー
  • 時間分解の光スペクトロスコーピー
  • 計算化学のアプローチ (DFT)

主要な成果

  • 3NTFにおけるチオール型ESIPTの実験的観測は,710 nmでの大きなストークスシフト放射 (1,230 cm−1) によって証明された.
  • 3MeNTFとの比較では,チオール陽子が欠け,472 nmで正常な放射を示している.
  • 超高速のESIPT速度 (<180 fs) と3NTFのタウトメア放出寿命は120 psである.
  • 計算による研究は,熱的に有利なESIPTを確認するが,非放射性誘導体の非放射性崩壊経路を明らかにする.

結論

  • 室温の溶液中のチオール型ESIPTに対する明確な実験的証拠
  • 3NTFのダイエチラミノ群は,興奮状態でππ*特性を促進し,突出したタウトマー放出を可能にします.
  • この研究は,非正規の硫黄水素結合を含むように,ESIPT化学の範囲を拡大する.

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