4座標のイリジウム (I) モノヒドリド:可逆的な二酸化窒素結合,結合活性化,および脱プロトン化
Matthew D Millard1, Curtis E Moore, Arnold L Rheingold
1Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, Mail Code 0358, La Jolla, California 92093-0358, USA.
Journal of the American Chemical Society
|June 17, 2010
まとめ
この研究では,ステリカルに阻害されたフォスフィンリガンドを使用して,四座標のイリジウム (I) モノヒドリド複合体を成功裏に分離し,特徴づけました. これらの発見は,化学的変換において,以前に仮定された反応性種の具体的な証拠を提供する.
科学分野:
- 有機金属化学 有機金属化学
- 協調化化学について
- カタリシス研究 カタリシス研究
背景:
- 4座標のイリジウム (I) モノヒドリド複合体は,様々な化学反応における反応性中間物質として提案されている.
- これらの種を隔離する以前の試みは,それらの固有の不安定性によって妨げられました.
- 頑丈なリガンドの開発は,一時的な有機金属種を安定化するために不可欠です.
研究 の 目的:
- 単離可能な四座標イリジウム (((I) モノヒドリド複合体を合成し,特徴づけること.
- これらの難解な種の存在に対する決定的な証拠を提供するためです.
- ステリカルに阻害されたフォスフィンリガンドを使用して,これらの複合体の反応性と安定性を調査する.
主な方法:
- メチレンアダマンチル置換のフォスフィンリガンド (L(mAd)) を使用したイリジウム複合体の合成.
- ディヒドリド塩化物の前駆体と有機金属反応剤 (PhMgBr, Li[HBEt(3) ]) の反応.
- 様々な条件下での光譜特性 (NMR) と反応性に関する研究 (N(2),H(2),H(2) O,Li[12-c-4]).
主要な成果:
- 平方平面のイリジウム (((I) モノヒドリド複合体,HIr (((N (((2)) (((L (((mAd)) (((2) とトライヒドリド複合体,H (((3) Ir (((L (((mAd)) (((2) の分離である.
- HIr (((N(2)) (((L(mAd)) (((2) とそのサイクロメタラ化形態であるH (((2) Ir (((kappa (((2) -P,C-L(mAd)) (((L(mAd)) の間のバランスの観察.
- ペンタヒドリドおよびダイヒドリドヒドロキシド複合体の生成は,それぞれH(2) とH(2) Oとの反応による.
- 安定した4座標のIr ((I) モノヒドリド塩, [Li ((12-c-4) ((2)) ][HIr ((kappa ((2) -P,C-L ((mAd)))) ((L ((mAd)) ]の形成.
結論:
- ステリカルに阻害されたL (((mAd) リガンドの使用により,以前には捉え難い4座標のイリジウム (((I) モノヒドリド複合体の分離が可能になった.
- これらの複合体は独特の反応性を発揮し,異なる反応条件下で様々なヒドリド種を形成します.
- この研究は,これらの重要な有機金属中間物質の基本的な化学を調査するための安定したプラットフォームを提供します.
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