ブロンステッド・フォトベースはルイス・フォトベースとして機能できますか?
Matthew J Voegtle1, Jahan M Dawlaty1
1Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States.
Journal of the American Chemical Society
|April 27, 2022
まとめ
研究者は,キノリンのような光塩基を用いて,光制御によるルイス酸塩相互作用を実証している. ボロン三化物などのルイス酸の移転を促し,新しい光触媒の可能性を提供します.
科学分野:
- 写真化学
- ルイス酸塩化学
- 光触媒
背景:
- デイティブ結合とルイス酸塩相互作用は,触媒と表面化学において根本的なものです.
- 光誘発型陽子移転 (興奮状態のブロンステッド酸性/塩基性) はよく確立された現象である.
- 光によるルイス酸塩相互作用の制御は未熟な領域である.
研究 の 目的:
- 光制御によるルイス酸塩相互作用を 調べるために
- ルイス酸を光刺激分子に変換する
- 陽子伝送の応用を超えた光塩基の可能性を探求する.
主な方法:
- ルイス酸としてボロン三化物 (BF3) と,光活性ルイス基としてキノリンを使用した.
- ルイス酸移転の駆動を定量化するために実験的なフォースターサイクルを構築しました.
- 時間依存密度関数理論 (TDDFT) と計算による検証のためのエネルギー分解分析を使用した.
主要な成果:
- 光活性化キノリンへのBF3移転に有意な熱力学的な駆動 (0. 2- 0. 7 eV) を示した.
- この駆動の大きさは,既知のブロンステッド光基本性効果に匹敵する.
- 計算分析により,その効果の起源は,ブロンステッド光活性に類似した置換効果と相関していることが明らかになった.
結論:
- 光刺激のルイス基は,興奮状態の陽子の移転に類似して,ルイス酸の移転を容易にする.
- 陽子の移転を超えた化学現象を制御するための新しいメカニズムを提供します.
- この研究は光触媒と光制御された化学反応に 新たな道を開きます
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