鉄カルベンの中間体による触媒C ((sp3) -Hアルキル化
Jennifer R Griffin1, Chloe I Wendell1, Jacob A Garwin1
1Roger Adams Laboratory, Department of Chemistry, University of Illinois , Urbana, Illinois 61801, United States.
Journal of the American Chemical Society
|September 13, 2017
まとめ
研究者は,C ((sp3) -Hアルキル化のための新しい鉄フタロシアニン触媒を開発し,C ((sp3) -C結合を形成する鉄カルベンの中間物質の以前の制限を克服した.
科学分野:
- 有機金属化学
- カタリシス
- 有機合成
背景:
- 触媒C ((sp3) -H結合の機能化は分子構造に不可欠である.
- 鉄カルベンの中間物質は,歴史的にC ((sp3) -Hアルキル化に限られた成功を収め,サイクロプロパネーションのような他の反応を好む.
- 以前の鉄触媒はC ((sp3) -H酸化とアミネーションに優れていたが,カルベンによるアルキル化には成功しなかった.
研究 の 目的:
- 鉄カルベンの中間物質を用いたC ((sp3) -HからC ((sp3) -C結合変換のための触媒システムを開発する.
- 鉄カルベン媒介のC ((sp3) -Hアルキル化のメカニズムを調査する.
- 触媒の改変によって触媒プロセスの調節性を証明する.
主な方法:
- 催化剤として鉄フタロシアニン複合体
- アリルおよびベンジルC ((sp3) -H結合のアルキル化.
- 運動分析と中間特徴付けを含むメカニズム研究.
主要な成果:
- アリル系およびベンジル系C ((sp3) -H結合の触媒性アルキレーションは,鉄フタロシアニン触媒を用いて成功しました.
- 機械学的研究は,電離性鉄カルベンが同解C-H分裂を媒介することを示した.
- C-H cleavageとリバウンドステップの両方が調節可能であることが判明し,C-H cleavageが部分的に速度を決定することを示唆しています.
結論:
- 鉄・フタロシアニン触媒は,鉄カルベンの中間体によるC ((sp3) -Hアルキル化を媒介することができ,以前は難解な変換であった.
- このメカニズムは,電離性鉄カルベンによって促進される同溶性C-H分裂を伴う.
- 触媒の設計は,鉄カルベンの惰性を克服し,効果的なアルキル化のためにC-H分裂を促進する鍵です.
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