高度還元された単成分コバルト複合体によって触媒化されたアルキン水酸化反応のメカニズム調査
Benjamin A Suslick1,2, T Don Tilley1,2
1Department of Chemistry, University of California, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|May 28, 2020
まとめ
この研究は,アルキンのオーソヒドロアリレーションの活性触媒として新しいコバルト ((-I) コンプレクスを特定した. 機械的調査は,協調されたメタリオン-デプロプロトネーション経路とZ選択性を明らかにする.
科学分野:
- 有機金属化学
- カタリシス
- 反応メカニズム
背景:
- オーソヒドロアリレーションのための以前のコバルト触媒には,定義されたメカニズムが欠けていました.
- 活性コバルトの種は特定されず,さらなる開発を阻害しました.
研究 の 目的:
- コバルト触媒によるオーソヒドロアリレーションのメカニズムを解明する.
- 活性コバルト種を特定し,基板依存性を理解する.
主な方法:
- 単離可能な減少コバルト複合体を用いたメカニズム分析.
- グリナード反応剤によるステキオメトリック反応と運動研究.
- 主要な同位体効果の測定
主要な成果:
- 単一成分コバルト ((- I) 複合体は活性前触媒として特定された.
- 触媒の起動にはβ-Hの除去/脱プロトン化が含まれます.
- C-H結合の活性化のために協調メタリオン-デプロトネーション (CMD) 機構が提案された.
- アルキンの調整は反応運動と選択性に影響する.
- コバルト ((-I) 種によるオレフィンのオフサイクルイソメリゼーションはZ選択性を決定する.
結論:
- コバルト ((-I) コンプレックスは,オルト・ヒドロアリレーションの高度に反応する触媒である.
- 反応は,速度を決定するC−H割れによるCMDメカニズムによって進みます.
- これらのメカニズムの理解は,アルキンの機能化のための合理的な触媒設計を可能にする.
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