安定した,しかし高度に反応する非古典的鉄 (II) ポリヒドリドピンカー複合体:終端アルキンのZ選択的二分化と水酸化
Nikolaus Gorgas, Luis G Alves1, Berthold Stöger
1Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa , Av. Rovisco Pais No. 1, 1049-001 Lisboa, Portugal.
Journal of the American Chemical Society
|June 7, 2017
まとめ
新しい鉄 (II) ポリヒドリド複合体は,アルキンの二酸化をエニンとビニルボロナート形成に触媒化する. これらの反応は,低触媒負荷を使用した穏やかな条件下で非常に選択的で効率的です.
科学分野:
- 有機金属化学
- カタリシス
- 合成化学
背景:
- 鉄の複合体は貴金属触媒の費用対効果が高く,持続可能な代替品です.
- ピンチャー・リガンドは,金属の中心部に対する安定性と制御を高めます.
- ポリヒドリド複合体は,触媒変換における多用途な中間物質である.
研究 の 目的:
- PNPピンサーリガンドによる新しい非古典的な鉄 (II) ポリヒドリド複合体を合成し,特徴づけること.
- アルキン変換におけるこれらの複合体の触媒的活動を調査する.
- 開発された触媒システムの範囲と選択性を調査する.
主な方法:
- トリデント酸PNPピンチリガンドを含む鉄 (II) ポリ水化物の合成.
- 顕微鏡技術 (例えば,NMR,X線結晶学) を用いた特徴付け.
- 軽度な条件下でアルキンの二酸化とボリル化を含む触媒反応.
主要な成果:
- [Fe(PNP) ((H) 2 ((η2-H2) ]複合体の合成に成功した.
- アリルアセチレンの効率的な触媒二分化により,高収量で1,3エニン結合.
- 末端アルキンとピナコルボランとの反応によるビニルボロ酸塩の形成.
- 両方の反応で高い化学的,地域的,ステレオ選択性 (最大99%のZ選択性) が観察されました.
結論:
- 非古典的な鉄 (II) ポリヒドリド複合体は,アルキンの機能化のための効果的な触媒である.
- これらの触媒システムは 価値ある有機化合物への持続的かつ効率的な経路を提供します
- 開発された方法論は,鉄触媒の可能性を強調し,製品形成を正確に制御します.
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