C5Me4SiMe3-リガートされた二核および三核クロミウム水素複合物による二酸化窒素活性化および水素化
Takanori Shima1,2, Jimin Yang3, Gen Luo3
1Advanced Catalysis Research Group, RIKEN Center for Sustainable Resource Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Journal of the American Chemical Society
|April 18, 2020
まとめ
この研究は,明確に定義されたクロミウム水化物複合体を用いて,第1回亜窒素 (N2) 裂解と水素化を実証している. 研究者は,クロムポリ水化物による新しい反応によって,N2の活性化と,その後の水素化を達成した.
科学分野:
- 有機金属化学
- 無機化学
- キャタリシス
背景:
- 金属水素による二酸化窒素 (N2) の活性化は窒素固定に不可欠ですが,依然として困難です.
- よく定義された金属複合体によるN2活性化に関する研究は限られている.
- クロミウムポリヒドリド複合体は,N2活性化の可能性を提供します.
研究 の 目的:
- C5Me4SiMe3結合した二核および三核クロミウムポリ水素複合体によるN2活性化および水素化を調査する.
- N2の分裂と水素化に関与する反応経路と中間物質を調査する.
- 明確に定義されたクロミウムヒドリド複合体によるN2分裂と水素化の最初の例を提示する.
主な方法:
- 二核および三核クロミウムポリ水化物複合体の合成と特徴付け
- 異なる条件下での水解反応 (希釈と濃縮溶液).
- 異なる温度での二酸化窒素 (N2) との反応
- 反応メカニズムを調査するための密度関数理論 (DFT) の計算.
主要な成果:
- 二酸化クロミウムと三核クロミウム四酸化クロミウム複合体の形成
- N2活性化と水素化により,四核二酸化物/二酸化物およびイミド/ニトリド/二酸化物複合体が生成される.
- ディニトリド中間物質の識別とイミド/ニトリド複合体への変換
- ダイミド/ダイヒドリド複合体を形成する可逆性ステレオイソメリゼーションと水素化の観察.
- 三核複合体とN2の反応により,ダイミド複合体が生じる.
- DFTの計算は,レート決定のステップとしてN2の組み込みをサポートしています.
結論:
- 明確に定義されたクロムポリヒドリド複合体は,二酸化窒素 (N2) を効果的に分割し,水素化することができる.
- この研究は,クロミウムヒドリド複合体によるN2分裂と水素化の最初の成功例を示しています.
- 反応メカニズムは,N-N結合の割れ,N-H結合の形成,およびC-H結合の活性化を含む.
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