ビス-N-ヘテロサイクリックカルベンのアミノピンサー・リガンドは,ル-触媒化エステル水素化における高活性性を可能にします
Georgy A Filonenko, Mae Joanne B Aguila1, Erik N Schulpen
1§DSM Innovative Synthesis BV, P.O. Box 18, 6160 MD Geleen, The Netherlands.
Journal of the American Chemical Society
|June 9, 2015
まとめ
ビス-N-ヘテロサイクリックカルベン (NHC) アミノピンサーリガンドは,エステルからアルコールへの効率的な触媒的水素化を可能にします. この新しいシステムは,低ルテニウム負荷で高い活性を達成し,従来の触媒の有望な代替品を提供します.
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
- グリーン・ケミストリー (Green Chemistry)
背景:
- エステルの水素化は,アルコールの生成に不可欠です.
- 従来の方法は,しばしば,繊細で高価なフォスフィンリガンドに依存しています.
- 新しい,堅牢で効率的な触媒システムの開発が必要である.
研究 の 目的:
- エステル水素化のためのbis-N-ヘテロサイクルカルベン (NHC) アミノピンサーリガンドを導入する.
- 新しいルテニウム-NHC複合体を合成し,特徴づけること.
- 新しいシステムの触媒性能を評価する.
主な方法:
- ビス-NHCアミノピンサーリガンドの合成.
- 二次元ルテニウム複合体の分離と特徴付け, [Ru2(L) 2Cl3]PF6.6.
- ルテニウム複合体を用いた様々なエステルの触媒性水素化.
主要な成果:
- 二次ルテニウム複合体は,エステル水素化において高い触媒活性を示した.
- エチルヘキサノアートの水素化のためのルテニウム負荷12.5ppmで283,000h−1までの初期活動を達成しました.
- アリファティックおよびアロマティックエステルの幅広いスペクトルを,相応のアルコールに高収量で成功裏に変換しました.
結論:
- ビス-NHCアミノピンサーリガンドは,エステル水素化の新しく効果的な触媒のクラスです.
- 開発された触媒システムは,高い効率と幅広い基板範囲を提供します.
- このアプローチは,従来のフォスフィンベースの触媒システムに対して,魅力的で空気安定な代替手段を提供します.
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