アルミニウム触媒を用いたC(sp3) -F結合の炭素-炭素結合
Weixing Gu1, Mason R Haneline, Christos Douvris
1Department of Chemistry, Texas A&M University, College Station, Texas 77842, USA.
Journal of the American Chemical Society
|September 3, 2009
まとめ
新しい触媒は,アルキアルミニウム化合物を用いて,アリファティックC-F結合のアルキラティブ除を可能にします. この選択的反応により,高精度でC-F債券をC-Me債券に変換する.
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:
- アリファティックC-Fボンドは,一般的に反応性がない.
- C-Fボンドの機能化のための既存の方法は,しばしば選択性が欠けているか,厳しい条件を必要とする.
研究 の 目的:
- アリファティックC−F結合のアルキル化のための効率的で選択的な触媒を開発する.
- この新しいアルキリル除反応 (AlkDF) のメカニズムと範囲を調査する.
主な方法:
- 触媒としてヘクサブロモカルボランアニオンとダイアキラアルミニウムカチオン等価物を使用した.
- アルキル化剤として,トリメチルアルミニウム (Me(3) アル) とトリエチルアルミニウム (Et(3) アルを含む様々なアルキルアルミニウム化合物を使用しました.
- 標準的な分析技術を使用して,変換と選択性を決定するために反応製品を分析します.
主要な成果:
- C ((sp ((3)) -F結合のアルキラティブ除 (AlkDF) のための効率的で長寿命の触媒を開発しました.
- C-F債券をC-Me債券に Me(3)Al.を使用した高忠実度変換が実証されました.
- C(sp(3)) -Fの債券だけが反応的であり,C(sp(2)) -Fの債券は影響を受けないことが観察されました.
- ハイドロデフローリネーションをEt(3) アルと競争する経路として特定し,競合するヒドリド対アルキル転送を示唆した.
- オーガノアルミニウム化合物が水に耐える能力を示し,反応条件を簡素化しました.
結論:
- ダイアルキルアルミニウム触媒は,アリファティックC-F結合のアルキラティブ除のための選択的で効率的な方法を提供します.
- この触媒系は,触媒化されていないC-F活性化に比べて,速度と選択性の増加を含む利点を提供します.
- この方法論は,モノフッ素アルカンおよびCF3基を含むアリファティックC−F結合を含む様々な基板に適用できます.
関連する概念動画
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