炭素−炭素結合形成反応に関連する分離された有機金属ニッケル (III) とニッケル (IV) コンプレックス
Jason W Schultz1, Kei Fuchigami1, Bo Zheng1
1Department of Chemistry, Washington University , One Brookings Drive, St. Louis, Missouri 63130-4899, United States.
Journal of the American Chemical Society
|September 7, 2016
まとめ
この研究は,炭素-炭素結合形成におけるニッケル (III) -ダイアルキル複合体の役割を初めて報告した. この発見は,ニッケル (III) とニッケル (IV) の種が,特にアルキル基板とのニッケル触媒クロスカップリング反応において重要なものであることを示唆している.
科学分野:
- 有機金属化学
- キャタリシス
- 合成有機化学
背景:
- ニッケル触媒は,電ophilesと立体化学的制御との汎用性のために,クロスカップリング反応で顕著になっています.
- パラジウムとは異なり,ニッケル触媒は偶数電子構成を含む複数の酸化状態に容易にアクセスし,Ni (III) の中間物質が一般的に提案されている.
研究 の 目的:
- Ni (III) -ダイアルキル複合体を分離し,特徴づけること.
- ニッケル触媒によるクロスカップリング反応中のC−C結合形成におけるNi (III) と潜在的に高い酸化状態の役割を調査する.
主な方法:
- Ni (III) -ダイアルキル複合体の分離と特徴付け
- ステキオメトリックと触媒C-C結合形成の研究
- 暫定的なNi (IV) 種のスペクトル観測と特徴付け
主要な成果:
- 最初のNi (III) -ダイアルキル複合体は,成功裏に分離されました.
- このNi (III) 複合体は,ステキオメトリックおよび触媒C-C結合形成の両方で活性を示した.
- 酸化剤の添加はC−C結合形成を加速し,一時的なNi (IV) 種を伴う.
- ニッケルサイクルのシステムで,Ni (IV) 種がスペクトル観測された.
結論:
- 孤立したNi ((III) -ダイアルキル複合体は,C−C結合形成における活性の高い中間物質である.
- 臨時性Ni ((IV) 種は,ニッケル触媒のクロスカップリング,特にアルキル基板で重要な役割を果たす可能性があります.
- Ni (III) と Ni (IV) の酸化状態は,ニッケル触媒のクロスカップリングメカニズムを理解するために重要である.
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