ハロゲン原子抽象反応のためのステイキオメトリックおよび触媒的フォトレドクタンとして発光するCe (III) コンプレックス
Haolin Yin1, Patrick J Carroll1, Jessica M Anna1
1P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34 Street, Philadelphia, Pennsylvania 19104, United States.
Journal of the American Chemical Society
|July 8, 2015
まとめ
新しいセリウム ((III) 複合体は発光し,炭素-ハロゲン結合から前例のない光化学的ハロゲン原子抽出を可能にします. この発見は,ランタナイドの光化学と触媒の新たな道を開く.
科学分野:
- 有機金属化学 有機金属化学
- フォトケミストリー フォトケミストリー
- ランタナイド化学 ランタナイド化学
背景:
- セリウム (III) 複合体は,そのユニークな電子特性で知られています.
- 彼らの興奮状態の振る舞いを理解することは,新しい光化学的アプリケーションの開発に不可欠です.
- ランタニド光化学は歴史的に範囲が限られていた.
研究 の 目的:
- 新しく発光するセリウム (III) 複合体を合成し,特徴づけること.
- これらの複合体の興奮状態の性質と電子構造を調査する.
- 光化学反応,特にハロゲン原子抽象化におけるこれらの複合体の可能性を調査する.
主な方法:
- Ce (III) 複合体の合成と特徴付け:Ce[N (Si) Me3) ]3 (1),1- (i) Pr,および1-Cy.
- 光学特性および寿命を決定するための光譜研究 (UV-Vis吸収,放射)
- 時間依存密度関数理論 (TD-DFT) の計算により,電子構造と興奮状態を明らかにする.
- C-X結合からハロゲン原子の抽象化能力を評価するための光化学実験.
主要な成果:
- C(3v) とC(2v) の対称性を有する発光Ce(III) 複合体を合成した.
- 4f → 5d電子移行による可視領域の吸収が観察されました.
- 553nm,518nm,523nmの放射帯を記録し,寿命は24ns,67ns,61nsであった.
- TD-DFTは,個別に占有されている5d(z(2)) 軌道を持つ (2) A1の興奮状態を明らかにした.
- ランタニドカチオンを使用して,sp(3) とsp(2) のC-X結合から光化学的ハロゲン原子抽象の最初の実証.
- 脱ヒロゲン化反応は,光敏感剤の触媒量によって成功裏に媒介されました.
結論:
- 合成されたCe (III) 複合体は,ユニークな発光特性とアクセシブルな興奮状態を有しています.
- 興奮状態の強烈な還元性は,新しい光化学的ハロゲン原子抽象反応を可能にします.
- この研究は,光化学におけるランタニド複合体の有用性を拡大し,脱ハロゲン化のための新しい触媒的アプローチを提供します.
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