エタン,プロパン,C4-C8の線形アルカン,およびチタン-炭素の多重結合によるいくつかの周期性アルカンの室温脱水
Marco G Crestani1, Anne K Hickey, Xinfeng Gao
1Department of Chemistry, Indiana University , Bloomington, Indiana 47405, United States.
Journal of the American Chemical Society
|August 29, 2013
まとめ
この研究は,一時的なチタンのノエペンチリジンの複合体が,線形アルケンを効率的に脱水させ,アルファ-オレフィン複合体を形成することを示しています. これらの複合体はさらに機能化され,または自由オレフィンを放出することができ,有機金属化学における多用途の反応性を示します.
科学分野:
- 有機金属化学 有機金属化学
- カタリシス カタリシス カタリシス
- 無機化学 無機化学とは
背景:
- タイタニウム複合体は,その触媒活性で知られている.
- アルケンの脱水化は,難しいが重要な変化です.
研究 の 目的:
- 暫定的なチタンのネオペンチリジネ複合体の脱水素化能力を調査するために.
- 新しいアルファ-オレフィンチタニウム複合体を合成し,特徴づけること.
- これらの複合体の反応性と安定性を調査する.
主な方法:
- 様々なアルカンとチタン複合体の脱水反応.
- タイタン-オレフィン複合体の合成と分離.
- 多核性NMRスペクトロスコーピー (HOESY,gHSQC,HMBC,dqfCOSYを含む) を使用した特徴付け.
- 結合と安定性を理解するための計算研究.
主要な成果:
- エタンをエチレンに効率的に脱水させ,C4-C8アルカンで安定したアルファ-オレフィン複合体を形成する.
- 複合体の合成 [{PNP}Ti{η}2) -H2CCHR{CH}2{t}Bu) ] (R = H,CH3,CH2CH3, (n) Pr, (n) Bu) である.
- 特徴づけにより,いくつかの複合体のダイアステロエーマーとエナチオーマーの形成が確認されました.
- 様々な反応剤 (N2O,アジド,ケトン,ディアゾアルカン) を使った複合物からオレフィン放出が実証されている.
結論:
- 暫定型チタンのノエペンチリジンの複合体は,アルカンの脱水化とアルファ-オレフィン複合体の形成のための多用途の反応剤です.
- ステリック要因は,その結果生成されたオレフィン添加物の安定性に大きく影響します.
- 合成された複合体は,制御されたオレフィン放出とさらなる機能化の経路を提供します.
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