NHC安定化ニッケル ((0) コンプレックスによるC-F活性化:選択性とメカニズムの調査
Thomas Schaub1, Peter Fischer, Andreas Steffen
1Institut für Anorganische Chemie der Universität Karlsruhe, 76131 Karlsruhe, Germany.
Journal of the American Chemical Society
|July 1, 2008
まとめ
ニッケル複合体は,フッ素化アレンおよびヘテロサイクルの炭素-フッ素結合を選択的に活性化します. これらの反応は,高い化学的および地域選択性を示し,機能化された芳香化合物を合成するための新しい経路を提供します.
科学分野:
- 有機金属化学 有機金属化学
- フロアンの化学的性質
- カタリシス カタリシス カタリシス
背景:
- 炭素-フッ素 (C-F) 結合の活性化は,フッ素化有機化合物の合成に不可欠である.
- ニッケル複合体は,そのユニークな反応性のために,C-F結合の活性化のためにますます探索されています.
- これらの反応の選択性とメカニズムを理解することは,新しい合成方法論の開発に不可欠です.
研究 の 目的:
- ニッケル複合体の反応を,様々なフッ素芳香化合物および異芳香化合物との反応を調査する.
- ニッケル複合体によるC-F結合活性化の化学的および地域選択性を決定する.
- C−F結合活性化プロセスのメカニズム的な詳細を解明する.
主な方法:
- [Ni2 (((i) Pr2Im) 4 (((COD)) ]と[Ni ((((i) Pr2Im) 2 (((eta (((2) -C2H4) ]の反応は,様々なフッ素アレンとヘテロサイクルの反応である.
- X線 difraksionを用いた製品の構造的特徴.
- 溶液中の反応中間物質の検出.
- 運動研究と密度関数理論 (DFT) 計算.
主要な成果:
- C-F結合の活性化において高い化学的および地域選択性が観察され,これはしばしば置換されたポリフッ化アルネのパラポジションで発生する.
- 選択的C-F活性化製品は,ヘクサフローロベンゼン,オクタフローロトルーエン,デカフローロビフェニル,ペンタフローロピリジンから合成されました.
- 主要な中間物質と製品の構造的特徴は,反応経路を確認した.
- 動力データとDFT計算は,C-F結合割れのためのアクティベーションパラメータを含む反応機構の洞察を提供した.
結論:
- ニッケル複合体は,予測可能な選択性を持つ様々なフッ素基板のC-F結合活性化を効率的に媒介する.
- この研究は,C-F活性化プロセスのメカニズム的理解を提供し,中間種の役割を強調しています.
- これらの発見は,新しいフッ素有機金属化合物および材料の標的型合成の道を開く.
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