テトラ核チタニウムイミド/ヒドリドフレームワークにおけるダイナトゲン活性化および水素化に関する実験的および計算的研究
Takanori Shima1,2, Gen Luo1,3, Shaowei Hu1
1Advanced Catalysis Research Group , RIKEN Center for Sustainable Resource Science , 2-1 Hirosawa , Wako , Saitama 351-0198 , Japan.
Journal of the American Chemical Society
|January 24, 2019
まとめ
この研究は,チタン複合体がイミドとニトリドリガンドに変換することによって窒素 (N2) を活性化する方法を示しています. これらの変換は,多金属チタンフレームワークにおけるヒドリド,イミド,およびニトリドリガンドの相互作用の重要な役割を強調しています.
科学分野:
- 無機化学
- 有機金属化学
- 材料科学
背景:
- 窒素 (N2) の活性化は化学における重要な課題であり,アンモニアや他の窒素を含む化合物の合成に不可欠である.
- 多金属複合体は,金属の中心間の協力効果により,ユニークな反応性を提供します.
- タイタニウム複合体は,N2結合と還元を含む多様な反応性で知られている.
研究 の 目的:
- 四核チタン (III) 複合体による分子窒素 (N2) の活性化を調査する.
- ハイドリド,イミド,およびニトリドリガンドを含む反応メカニズムを解明する.
- 異なる条件下でチタン-窒素種の変換を調査する.
主な方法:
- 異なる温度と圧力での固体反応を含む実験研究.
- 反応経路をモデル化するための密度関数理論 (DFT) の計算.
- 中間物質と製品複合体のスペクトル学的特徴付け
主要な成果:
- テトラ核のチタン (III) ディミド/テトラヒドリド複合体 (Cp'Ti) 4 (μ3-NH) 2 (μ-H) 4) が合成された.
- 180 °CでのN2と反応すると,N2の割れと部分的水素化を含むダイナトリド/ダイミド複合体,Cp'Ti) 4<μ3-N) 2が得られる.
- 130 °Cでの脱水化により,N2で加熱すると,ダイナトリド/テトラヒドリド複合体,[(Cp'Ti) 4(μ3-N) 2(μ-H) 4が形成され,ダイナトリド/ダイミド複合体に変換された.
- ディニトリド/ダイミド複合体の水素化により,テトラマイド複合体, (Cp'Ti) 4 (μ3-NH) 4が生じる.
結論:
- この研究は,ヒドリド,イミド,およびニトリドの複合体における複雑な相互作用を示しています.
- イミドおよびニトリド種の可逆脱水/水素化は,N2活性化に不可欠である.
- 多金属チタンフレームは,これらの窒素変換を媒介する上で重要な役割を果たします.
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