鉄から窒素-炭素結合の形成のメカニズム
Samuel M Bhutto1, Reagan X Hooper1, Brandon Q Mercado1
1Department of Chemistry, Yale University, 225 Prospect St., New Haven, Connecticut 06520, United States.
Journal of the American Chemical Society
|February 16, 2023
まとめ
この研究は,アレンと窒素ガス (N2) の反応によってN-C結合を形成するメカニズムを明らかにしている. 鉄触媒でシリレーションとアリル移行がどのように起こり,Nを含む化合物の合成を可能にするかを詳細に説明しています.
科学分野:
- 有機金属化学
- キャタリシス
- 窒素固定
背景:
- 前回の反応配列は,アレン内のC-H結合とN2内のN-N三重結合を活性化し,N-C結合を形成する.
- このプロセスは豊富な原料を N 含有有機化合物に変換します.
- シリル化とアリル移行によるN-C結合形成のメカニズムは不明のままである.
研究 の 目的:
- アレンとN2を含むN-C結合形成のステップ・バイ・ステップメカニズムを解明する.
- 還元,シリレーション,アリル移動の作用を触媒サイクルで理解する.
- 主要な中間物質の電子構造と反応性を調査する.
主な方法:
- 中間物質の合成と構造的特徴
- 磁気学,スペクトル学,運動学の研究
- 密度関数理論 (DFT) とCASSCF計算モデリング.
主要な成果:
- N2は,アリル移動の前に,ディスタル窒素で二重シリレーションを必要とする.
- 連続したシリル基とシリルカチオンを加えた経路は,分離可能な鉄 ((IV) -NN ((SiMe3) 2を形成する.
- 動力学的研究は,中間物質から製品への第一順位の変換を確認します.
- DFTの計算は,アリル移動のための協調された移行状態を明らかにします.
- 電子構造の計算では,Fe (II) /Fe (III) 状態と電愛性N原子からの共振寄与が示されている.
結論:
- アレンとN2からN-C結合形成の詳細なメカニズムが確立されている.
- このメカニズムは,連続したシリレーション,独特の鉄 (IV) 中間物質の形成,および協調したアリル移動を含む.
- この研究は,N2の機能化のための新しい有機金属戦略を提供します.
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