分子間Zr(IV) -フォスフィンの挫折したルイス対による小分子活性化
Owen J Metters1, Sebastian J K Forrest1, Hazel A Sparkes1
1School of Chemistry, University of Bristol , Cantock's Close, Bristol BS8 1TS, United Kingdom.
Journal of the American Chemical Society
|January 21, 2016
まとめ
新しい分子間トランジションメタル (FLP) は,D2やCO2のような小さな分子を活性化します. これらのシステムは調節可能な性質を提供し,DOSY NMRを通じてルイス酸/塩基相互作用を明らかにします.
科学分野:
- 有機金属化学
- キャタリシス
- 超分子化学
背景:
- 挫折したルイスペア (FLP) は小分子活性化に不可欠です.
- 以前は,分子内FLPのみが広範な反応性を示していた.
- 分子間FLPは,ステリックおよび電子特性においてより高い調節性を提供します.
研究 の 目的:
- 新しい分子間移行金属FLPを開発し特徴づけること.
- これらの新しいFLPの小分子活性化能力を探求する.
- FLPの反応性および選択性に対するステリックおよび電子的要因の影響を調査する.
主な方法:
- 10つの新しいジルコノセンのアロキシドとフォスフィンベースの分子間FLPの合成
- D2,CO2,THF,PhCCHを含む小分子との反応
- ルイス酸と塩基の相互作用を明らかにするためのDOSY NMRスペクトロスコーピー.
主要な成果:
- D2,CO2,THF,PhCCHとの広範な小分子活性化化学を実証した.
- 調整可能な性質を持つ10の新しい分子間移行金属FLPを成功裏に合成しました.
- トルマンのステリックパラメータが小さいフォスフィンは,非常に反応性があり,選択的なFLPを生成することを特定しました.
- DOSY NMRを用いて,これらのシステムにおけるルイス酸と塩基の相互作用について,初めて洞察を提供した.
結論:
- 分子間FLPは,分子内システムと競合する広範な小分子活性化を達成できます.
- ルイス基成分を体系的に変化させることで,FLPの反応性と選択性を微調整することができます.
- 変形金属FLPの反応性と選択性の両方を強化する.
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