活性化されていない末端および内部オレフィンとトリフローロメチル置換アーレンの線形選択的水酸化
Joseph S Bair1, York Schramm, Alexey G Sergeev
1Division of Chemical Sciences, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|August 30, 2014
まとめ
この研究では,活性化されていないオレフィンとトリフローロメチル置換アレンから線形アルキラーレンを生成するための新しい水酸化法が導入されています. 反応は,高選択性で進行し,可逆的な中間生成と速度を決定する還元性除去を含むユニークな触媒機構によって駆動されます.
科学分野:
- 有機化学 オーガニック・ケミストリー
- カタリシス カタリシス カタリシス
- 有機金属化学 有機金属化学
背景:
- ハイドロアリレーション反応は,アルキラーレン化合物の合成に不可欠です.
- 誘導群は,非活性化オレフィンの水素アリレーションにおける高い選択性のために通常必要である.
- 既存の方法には,しばしば効率が欠け,または難しい基板に対して選択性が欠けている.
研究 の 目的:
- 活性化されていないオレフィンとトリフローロメチル置換アレンを選択的に水酸化する.
- 中間形成と速度決定のステップを含む反応機構を調査する.
- 誘導グループを必要とせずに,線形アルキラーレン製品の高い選択性を達成する.
主な方法:
- ハイドロアリレーション反応のためのニッケル触媒を用いた.
- ラベル付け実験を含む実験的メカニズム研究に従事した.
- 密度関数理論 (DFT) を用いた計算研究を行った.
主要な成果:
- 活性化されていないオレフィンとトリフローロメチル置換アレンによる線形水酸化成分の高い選択性を達成した.
- 内部,アサイクリックオレフィンの成功した水酸化により,線形アルキラーレンの生成物が得られることが実証されています.
- アルキルニッケル-アリル中間物質の可逆的形成と速度を決定する還元性除去を主要なメカニズム特性として特定した.
- 内部アルケンから端末アルキラーネの形成には,初期アルケンの異体化が伴うことを示した.
- 計算による研究は,C−H結合の移転とレート決定の還元性排除に関する実験的発見を裏付け,アンチ・マルコヴニコフ製品を形成した.
結論:
- 活性化されていないオレフィンの汎用的で高度に選択的なニッケル触媒化水酸化を開発した.
- イソメリゼーションと還元性除去を含む新しい触媒機構を明らかにした.
- 同性化によるα-オレフィン濃度に対する反応の逆順序の依存性は,その触媒効率の鍵である.
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