イリジウムによるヒドラジンのN-H活性化. ダブルN-H活性化により,イリジウムアミノニトレン複合体を形成する
Zheng Huang1, Jianrong Steve Zhou, John F Hartwig
1Department of Chemistry, University of Illinois, 600 South Mathews Avenue, Urbana, Illinois 61801, USA. jhartwig@illinois.edu
Journal of the American Chemical Society
|August 3, 2010
まとめ
イリジウムピンサー複合体は,ヒドラジンのN-H結合を割って,ヒドラジドおよびアミノニトレン複合体を形成します. また,いくつかの反応ではN-N結合が割れ,さまざまなイリジウム産物や窒素を含む化合物が生成されます.
科学分野:
- 有機金属化学 有機金属化学
- 無機化学 無機化学とは
- カタリシス カタリシス カタリシス
背景:
- ピンチャー・リガンドは,反応性金属の中心を安定させる上で重要な役割を果たします.
- ヒドラジン誘導体は,協調化学における多用途の窒素源である.
- N-HとN-N結合の活性化を理解することは,窒素の固定と機能化の鍵です.
研究 の 目的:
- イリジウム (((I) ピンサー複合体とヒドラジン誘導体の反応性を調査する.
- N-HとN-Nの結合分裂のメカニズムを探求する.
- 新しいヒドラジドおよびアミノニトレン・イリジウム複合体を合成し,特徴づけること.
主な方法:
- アロマティック (PCP) とアリファティック (D(t) BPP) リガンドを持つイリジウム (I) ピンサー複合体の合成.
- イリジウム複合体の様々なヒドラジン誘導物 (ベンゾフェノンヒドラゾン,1-アミノピペリジン,メチル置換ヒドラジンなど) との反応.
- 反応産物の特性分析は,光譜技術とX線結晶学を用いて行われます.
主要な成果:
- ハイドラジンの単一N-H結合割れは,ヒドラジド複合体を産生する.
- 双胞胎のダブルN-H分裂は,異常なアミノニトレン複合体につながります.
- N-N結合の分裂は,いくつかの反応で観察され,イソシアン酸イリジウム (III) 二酸化水素複合体およびアンモニアを含む多様な製品を形成します.
- アミノニトレン複合体のCOまたは酸化添加反応剤との反応により",イソジアジン"断片が放出されます.
結論:
- イリジウムピンサー複合体は,ヒドラジン誘導体のN-HとN-N結合を効果的に活性化します.
- ピンサー・リガンドとヒドラジン基質の性質は,反応経路と産物分布に影響する.
- この研究は,遅い移行金属アミノニトレン複合体の形成のための新しい経路を明らかにし,窒素化学におけるイリジウムの汎用性を強調しています.
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