2,2'-ビピリジルリガートゴールドセンターでの酸化添加,転金属化,および還元性除去
Matthew J Harper1, Christopher J Arthur1, John Crosby1
1School of Chemistry , University of Bristol , Bristol , BS8 1TS , United Kingdom.
Journal of the American Chemical Society
|March 20, 2018
まとめ
この研究は,ビアリル化合物を合成するための新しい金複合体を導入します. この金で触媒化された方法は,パラジウム触媒を模倣し,グループを指示することなく有機合成のための新しい経路を提供します.
科学分野:
- 有機金属化学
- カタリシス
- 合成有機化学
背景:
- パラジウム触媒によるクロスカップリング反応はビアリル合成の標準です.
- 代替的触媒システムの開発,特に土壌に豊富な金属の使用は極めて重要です.
- 黄金の触媒は,C−C結合形成のためのユニークな反応性プロファイルを提供します.
研究 の 目的:
- ビアリル合成のための新しいモノメタリックゴールド複合体を開発する.
- 黄金を用いてパラジウム触媒によるビアリル合成の特徴である全ての触媒的ステップを実証する.
- 主要なステップのメカニズム,特に酸化添加を調査する.
主な方法:
- 3座標のビピリジルゴールド複合体の合成
- 黄金の中心にアリルイオジドを触媒的に添加する.
- アリル-亜鉛伝達とC-C還元性除去
- 顕微鏡法を用いた製品の特徴づけ
- 反応メカニズムの解明のための計算研究.
主要な成果:
- 簡単に合成された金-バイピリジルエチレン複合体.
- 単一の金複合体から連続した酸化添加,伝達,および還元除去が実証されています.
- 電子が豊富なアリルイオジドは酸化添加段階においてより速く反応することを確認した.
- 計算分析により,酸化添加の可逆性および基板選択性に関する洞察が得られた.
結論:
- パラジウム触媒を模倣したビアリル合成のための新しい金触媒経路が確立されています.
- この金ベースのシステムは グループを指揮する必要なく 効率的に動作します
- この研究は,金触媒によるC−C結合形成のメカニズム的理解を提供し,さらなる金触媒開発の道を開いている.
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