トリメチルスカンジウム
Damir Barisic1, Dominic Diether1, Cäcilia Maichle-Mössmer1
1Institut für Anorganische Chemie , Eberhard Karls Universität Tübingen , Auf der Morgenstelle 18 , 72076 Tübingen , Germany.
Journal of the American Chemical Society
|August 1, 2019
まとめ
新しいスカンジウムテトラメチルアルミナート複合体が合成され,特徴づけられました. この複合体[Sc(AlMe4) 3は,ユニークな反応性を示し,スカンジウムメチル複合体とイソプレンポリメリゼーションの前駆体として機能する.
科学分野:
- 有機金属化学
- 協調化学
- ポリマー化学
背景:
- アルミニウムアルキルリガンドを持つスカンジウム複合体は十分に理解されていません.
- テトラメチルアルミナートリガンドは,ユニークな電子およびステリック特性を提供します.
- ポリメリゼーション触媒のための新しい前駆物質の開発は重要な関心事である.
研究 の 目的:
- 新型ホモレプス型テトラメチルアルミナート・スカンジウム複合体を合成し,特徴づけること.
- 新しい複合体の反応と分解の経路を調査する.
- スカンジウム-アルミニウム複合体のポリメリゼーション触媒としての可能性を調査する.
主な方法:
- 低温で[Li3ScMe6(thf) 1.2とAlMe3から[Sc(AlMe4) 3を合成する.
- コクリスタル化と構造的特徴づけ [Sc (Al) Me4) 3 (Al) Me6) 0.5
- C-H活性化とNMRスペクトル (45Sc NMR) による分解試験
- トリメチルトリアザサイクロンナン (Me3TACN) と塩の転移反応による誘導.
- イソプレンのポリメリゼーションは,カチオン化複合体を触媒として使用します.
主要な成果:
- 新型ホモレプティックテトラメチルアルミナート複合体[Sc(AlMe4) 3が成功して合成された.
- C-H活性化を含む分解経路は,混合メチル/メチリデン複合体を導いた.
- [Me3TACN]ScMe3を含むスカンジウムメチル複合体が形成され,特徴づけられました.
- [Cp*Sc(AlMe4) ]のような半サンドイッチおよびサンドイッチ複合体を得ました.
- 45Sc NMRスペクトロピーは[ScMe3]の存在を確認し,有意な脱シールドを示した.
- カチオン化された複合体は,高収量およびシス-1,4-ポリイソプレン含有量でイソプレンポリメリゼーションを触媒化した.
結論:
- [Sc(AlMe4) 3の合成は,既知のオルガノカンジウム化学を拡張する.
- 複合体は,C-H活性化とリガンド交換を含む豊富な反応性を表しています.
- スカンジウム-アルミニウム複合体は,ステレオ選択性イソプレンポリメリゼーションの触媒として有望である.
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