ステイキオメトリック反応と反応性内分子Zr(+) /アミンの反応性による触媒性水素化により,ルイス対が挫折した
Xin Xu1, Gerald Kehr1, Constantin G Daniliuc1
1Organisch-Chemisches Institut, Universität Münster, Corrensstrasse 40, D-48149 Münster, Germany.
Journal of the American Chemical Society
|March 18, 2015
まとめ
新型ジルコニウムベースのフラストラテッド・ルイス・ペア (FLP) 触媒は,穏やかな条件下でアルケンとアルキンの効率的な水素化を容易にする. この有機金属製のFLPは,ヘテロリティック二水素の割れと,H ((+) / H ((-)) の転移を触媒用途で可能にします.
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
- 挫折したルイス・ペア.
背景:
- フラストラテッド・ルイス・ペア (FLP) は,クラシック・アダクトを形成できないルイス酸と塩基であり,ユニークな反応性をもたらします.
- ジルコニウム複合体は,その電子特性により,新しいFLPプラットフォームとしての可能性を秘めています.
研究 の 目的:
- 新しいジルコニウムベースのFLPを合成し,特徴づけること.
- 小分子に対するこのFLPの反応性と,その触媒的可能性を調査する.
主な方法:
- ペンダントアミンリガンドによるジルコニウム複合体の合成.
- FLPを生成するトリチルカチオンによるジルコニウム複合体の活性化.
- ディクロロメタン,二水素,不飽和基質との反応.
主要な成果:
- ジルコニウム前駆体 (13) から反応性Zr(+) /アミンFLP (14) を生成する.
- CH2Cl2,H2,アルキンなどの反応を含むFLPの反応性の実証.
- 軽度な条件 (室温,1.5 bar H2) の下でFLP 14を使用してアルケンおよび内部アルキンの触媒水素化をします.
結論:
- Zr(+) /アミンのFLP (14) は,水素化反応の効果的な触媒である.
- FLPシステムは,効率的な二水素活性化とH ((+) /H ((-)) 転送能力を有しています.
- 軽度の反応条件と低触媒負荷 (1-4モル%) は,この触媒システムの実用的な有用性を強調しています.
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