二座標のd9複合体. 二座標のd9複合体. 二座標のd9複合体. NHCニッケル (((I)) アミドの合成と酸化
Carl A Laskowski1, Gregory L Hillhouse
1Gordon Center for Integrative Science, Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|September 27, 2008
まとめ
新型ニッケル ((I) コンプレックスと大容量のリガンドが合成されました. これらの複合体は酸化と再配置反応を経て,ユニークなイミノシランと二次元ニッケル構造を生み出し,オルガンニッケル化学を拡張します.
科学分野:
- 有機金属化学 有機金属化学
- ニッケル・カタリシス
- 協調化化学について
背景:
- 低調整ニッケル複合体は,触媒の重要な中間物質である.
- その反応性を理解することで,触媒サイクルについての洞察が得られます.
- ステリー的に要求されるリガンドは,ニッケル複合体の安定性と反応性を影響する.
研究 の 目的:
- 新規の単体,2座標のNi (I) 複合体を合成し,特徴づけること.
- これらのNi ((I)) 複合体の酸化時の反応性を調査する.
- 珍しいニッケル含有構造の形成を調査する.
主な方法:
- ニッケル (I) クロリドジマーと大量のアミド/アニリドリガンドからニッケル (I) コンプレックスを合成する.
- 合成されたニッケル (((I)) コンプレックス.の電気化学的酸化.
- スペクトロスコーピテクニックとX線結晶学 (暗示) を用いた製品の特徴付け.
主要な成果:
- モノメア,二座標ニオンの複合体の成功合成: (IPr) Ni{N(SiMe3) 2} (2) と (IPr) Ni(NHAr) (3).
- 複合体2の酸化によりβ-Meが除去され,塩基安定化イミノシラン複合体 [(IPr) Ni(CH3) {kappa1-N(SiMe3) =SiMe2.Et2O}][BArF4] (6) が形成された.
- 複合体3の酸化により,THFの喪失により二次構造 (5) に再編成されるカチオンのエタ3協調複合体 (4) が生成された.
結論:
- 大量のN-ヘテロサイクリックカルベン (IPr) リガンドを持つ新しい2座標Ni (I) 複合体のアクセシビリティが実証されました.
- 1電子酸化時にβ-Meの除去とリガンドの再配置を含むユニークな反応経路を明らかにした.
- 前例のないイミノシランと二重ニッケル種を形成することによって,オルガンニッケル化学の範囲を広げました.
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