活性化されていないアルキル塩化物のマンガン触媒によるボリレーション
Thomas C Atack1, Silas P Cook1
1Department of Chemistry, Indiana University , 800 East Kirkwood Avenue, Bloomington, Indiana 47405-7102, United States.
Journal of the American Chemical Society
|May 10, 2016
まとめ
この研究は,アルキルハリドの新たなマンガン誘導クロスカップリング反応を導入し,多様なボロンエステルの効率的な合成を可能にします. この方法は,低触媒負荷と制御された反応結果で高収量を提供します.
科学分野:
- 有機化学
- カタリシス
- 有機金属化学
背景:
- アルキルハリドは有機合成の重要な構成要素である.
- アルキルハリドの機能化のための効率的な触媒的方法の開発は,依然として重要な課題です.
- マンガンの触媒は,貴金属触媒の費用対効果が高く,持続可能な代替手段です.
研究 の 目的:
- アルキルハリドのための新しいマンガン触媒クロスカップリング反応を開発する.
- 初級,二級,三級のボロンエステルの合成を実証する.
- 反応のメカニズムを調査し,反応の結果を制御する.
主な方法:
- 低コストのマンガン (II) ブロミド (MnBr2) とテトラメチルエチレンダイアミン (TMEDA) を触媒として使用する.
- アルキルハリドとのクロスカップリングのためのボルン源として (bis) ピナコラートジボロンを使用します.
- 反応経路の解明のために 激素時計実験を行っています
主要な成果:
- クロリドを含む幅広いアルキルハリドの効率的なクロスカップリングを達成した.
- 合成された初等,二次,三次性ボロンエステルは高収量である.
- 触媒の負荷が1000ppmと反応時間が速い (5mol%で30分) で,高い触媒効率が実証されている.
- ラジカルクロック実験では,直接ボリレーションが0°Cでのラジカルプロセスに優れていることが示された.
結論:
- この研究は,アルキル電ophilesとの最初のマンガン触媒クロスカップリング反応を提示します.
- 開発された方法は,合成的に価値のあるボロンエステルへの多用途かつ効率的な経路を提供します.
- この反応は調節可能で温度制御された結果をもたらし,合成の有用性を高める.
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