アルキンをカルベンの前駆体として用いる触媒B-H結合挿入反応
Ji-Min Yang1, Zi-Qi Li1, Mao-Lin Li1
1State Key Laboratory and Institute of Elemento-Organic Chemistry, Nankai University , Tianjin 300071, China.
Journal of the American Chemical Society
|February 15, 2017
まとめ
移行金属触媒は,ボーラン添加物とアルキンの間のB-H結合挿入反応を可能にし,オルガノボロン化合物を生成します. この新しい方法は,高収量,原子経済,キラルボランへの非対称な経路を提供します.
科学分野:
- 有機金属化学
- 有機合成
- カタリシス
背景:
- トランジションメタルの触媒は,新しい合成方法論の開発に不可欠です.
- オーガノボロン化合物は,有機合成における多用途の中間物質である.
- B-H結合の機能化のための効率的な方法は,非常に求められています.
研究 の 目的:
- ボラン添加物とアルキンの間の新しい移行金属触媒BH結合挿入反応を報告する.
- キラルオルガノボロン化合物の合成のための非対称な触媒システムを開発する.
- 反応のメカニズムと運動を調査する.
主な方法:
- 移行金属 (例えば,銅,ディロジウム複合体) を用いた触媒.
- 軽度な条件下でアルキンとボラン添加物の反応.
- キラルディロジウム複合体を使った非対称な触媒.
- 運動学の研究と密度関数理論 (DFT) の計算.
主要な成果:
- オーガノボロン化合物を合成した
- 100%の原子経済を達成しました.
- キラルボランの非対称合成における高エナンチオ選択性 (最大96% ee).
- キラルボランを,光学的な純度を失うことなく,ボラートおよびダイアリルメタノール化合物へと容易に変換することが示されている.
- キネティクスは,Cu-触媒反応における速度制限ステップとしてCuカルベンの形成を示している.
結論:
- B−H結合の挿入によるオルガノボロン化合物の新しい,効率的で原子経済的な経路が確立されている.
- 高度にエナチオセレクティブな非対称な触媒システムの開発は,キラル分子を合成するためのこの反応の有用性を拡大する.
- 機械的洞察は,有機合成におけるこの方法論のさらなる最適化と適用のための基礎を提供します.
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