水素原子抽象化 μ-1,2-超酸化二銅 (II) 複合体の熱力学
Nicole Kindermann1, Can-Jerome Günes1, Sebastian Dechert1
1Universität Göttingen , Institut für Anorganische Chemie, Tammannstraße 4, D-37077 Göttingen, Germany.
Journal of the American Chemical Society
|July 11, 2017
まとめ
ピラゾラート基のディコッパー (II) 複合体は安定したμ-1,2-スーパーオクソディコッパー (II) 複合体に酸化された. このスーパーオクソ複合体は 水素原子の抽象化に関与し 銅と酸素の化学反応を明らかにしています
科学分野:
- 無機化学
- 協調化学
- バイオ有機化学
背景:
- 銅と酸素の複合体は 生物学的システムと触媒に不可欠です
- 酵素活性部位を模倣するために,ペロクソとスーパーオクソディコッパー種の反応性を理解することが不可欠です.
研究 の 目的:
- ピラゾラート基のμ-1,2-ペロクソ二銅 (II) 複合体を合成し,特徴づけること.
- この複合体の電気化学的酸化とその後の反応性を調査する.
- 二酸化銅種を含む水素原子抽象のメカニズムと熱力学を解明する.
主な方法:
- μ-1,2-ペロクソ二銅 (II) 複合体の電気化学的酸化
- 発生したμ-1,2-スーパーオクソ二銅 (II) 複合体のスペクトル解析 (IRスペクトル解析)
- 構造と電子分析のための密度関数理論 (DFT) の計算.
- 水素原子抽象反応の運動と熱力学的分析
- 熱力学正方形の解析
主要な成果:
- ピラゾラート基のμ-1,2-ペロキソ二銅 (II) 複合体 (1) を,安定したμ-1,2-スーパーキソ二銅 (II) 複合体 (3) に−0.59V対Fc/Fc+で1電子酸化する.
- 顕微鏡による特徴づけにより,スーパーオクソ種の形成が確認された (ν̃(O-O) = 1070 cm−1, Δ(18O-16O) = -59 cm−1).
- 複合体3はμ-1,1-ヒドロペロキソ二銅 (II) 複合体からH原子を抽出することによって形成され,またTEMPO-HからH原子を抽出して2を再生することができた.
- これらのH原子抽象プロセスで特定された協調した陽子電子伝送経路.
- 複合体 2 の OO-H 結合に対する 71.7 ± 1.1 kcal mol−1 の結合解離自由エネルギー.
結論:
- この研究では,安定したμ - 1,2 - スーペロキソ・ディコッパー (II) 複合体を合成し,特徴づけました.
- スーパーオクソ複合体の電気化学および化学反応性は,銅-酸素中間物質の洞察を提供します.
- この発見は,ダイコッパーオクソ種によるH原子抽出における協調した陽子電子伝送機構を支持し,触媒サイクルへの影響を及ぼしている.
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