グループ3の化学における複数のC−H結合の活性化:イトリウム・アルミニウム・メチンのクラスタの合成と構造的特徴化
H Martin Dietrich1, Hilde Grove, Karl W Törnroos
1Department of Chemistry, University of Bergen, Allégaten 41, N-5007, Bergen, Norway.
Journal of the American Chemical Society
|February 2, 2006
まとめ
Cp*Y(AlMe4) 2のドナー誘発した割れは[Cp*Y(mu2-Me) ]3.2を生成する. 対照的に,ダイエチルエーテルとの反応は,C-H活性化とイトリウム-アルミニウム-メチンのクラスター形成につながり,有機金属反応性についての洞察を明らかにします.
科学分野:
- 有機金属化学 有機金属化学
- メイングループ 化学
- カタリシス カタリシス カタリシス
背景:
- 半メタロセノ複合体は,ユニークな反応経路を提供しています.
- アルキアルミニウム化合物は,有機金属合成における多用途な前駆体である.
- ドナー-リガンドの相互作用は,金属-アルキル結合の割れ方を著しく影響する.
研究 の 目的:
- 異なる量のダイエチルエーテルとCp*Y(AlMe4) 2の反応性を調査する.
- アルキルアルミナートの割れ方とC-H活性化のメカニズムを探求する.
- 新しいイットリウム-アルミニウム複合体を合成し,特徴づけること.
主な方法:
- 異なるステキオメトリック条件下でCp*Y(AlMe4) 2をダイエチルエーテルで処理する.
- X線結晶学のような技術を用いた結果の複合体の構造的特徴化.
- ドナー誘発の分裂とC-H結合の活性化を含む反応経路の分析.
主要な成果:
- 2等価のダイエチルエーテルによるCp*Y(AlMe4) 2の完全な割れは95%の収量で[Cp*Y(mu2-Me) ]3が得られました.
- ディエチルエーテルとの等価反応により,C-H活性化による[Cp*4Y4(mu2-CH3) 2{(CH3) Al(mu2-CH3) 2}4(mu4-CH) 2の低収量 (10-30%) が得られました.
- ヘテロオクトメタリックイトリウム-アルミニウム-メチンのクラスタの合成は,47%の収穫率で達成されました.
結論:
- ドナー添加のステキオメトリが反応経路を決定する:C-H活性化とC-H分裂.
- プリフォームされたY-CH3-Al分子は,基本的反応剤による水素抽出に敏感です.
- 構造的特徴は,新しいモノサイロペンタディエニルイトリウム-アルミニウム複合体の形成を確認した.
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