ディセレニド・ディニッケル ((II) 複合体によるC-H活性化
Jessica Wallick1, Charles G Riordan, Glenn P A Yap
1Department of Chemistry and Biochemistry, University of Delaware , Newark, Delaware 19716, United States.
Journal of the American Chemical Society
|September 27, 2013
まとめ
ニッケル (I) コンプレックスにセレニウムを加えると,ディニッケル (II) ディセレニドコンプレックスを形成する. この複合体は基板を酸化し,セレニウム形態の間で変換することができ,ニッケル複合体のダイナミックなセレニウム化学を示しています.
科学分野:
- 無機化学 無機化学とは
- 有機金属化学 有機金属化学
- 協調化化学について
背景:
- ニッケル複合体は,様々な化学変換における多用途な触媒である.
- セレニウムリンガンドは,生物学的システムと無機触媒で重要な役割を果たします.
- セレニウムを含む金属複合体の反応性を理解することは,新しい触媒プロセスを開発するための鍵です.
研究 の 目的:
- 新規のディニッケル (II) ディセレニド複合体を合成し,特徴づけること.
- 合成された複合体の酸化還元反応と反応性を調査する.
- 基板酸化およびセレニウム移転反応におけるこの複合体の可能性を調査する.
主な方法:
- ニッケル (((I) の前駆体複合体[Ni (((Me4[12]aneN4) (((CO) ]PF6.6の合成
- 元素セレニウムとのレドックス反応により,ディニッケル (d) ディセレニド複合体 (d) が形成されます.
- ディセレニド複合体の構造を決定するX線結晶学.
- 9,10-ジヒドロアントラゼンと1,4-サイクロヘキサジエンによる酸化反応.
- その結果得られるヒドロセレニド複合体の特徴と,それを再びディセレニド・アダクトに変換する.
主要な成果:
- [Ni(Me4[12]aneN4)(CO) ]PF6にセレニウムを加えると, 70%の収穫でディニッケル (II) ディセレニド複合体 {[Ni(Me4[12]aneN4) ]2(Se2) }を生成した.
- 結晶構造はμ-η(2):η(2)-Se2リガンドを明らかにし,Se-Se結合の長さは2.379(13) Åであった.
- ディニッケル (II) ディセレニド複合体は,加熱すると9,10-ジヒドロアントラセンと1,4-サイクロヘクサジエンが酸化し,端末の水素セレニド複合体 [Ni(Me4[12]aneN4) (((SeH) ]PF6.6を形成した.
- ハイドロセレニド複合体は,フェノキシ根幹との反応により,デセレニド複合体へと再生された.
結論:
- 新しいディニッケル (II) ディセレニド複合体が合成され,構造的に特徴づけられた.
- 複合体はダイナミックな酸化還元作用を呈し,基板の酸化とセレニウム移転を促進します.
- この研究は,リドックスプロセスとセレニウム化学を含む触媒応用におけるニッケル-セレニウム複合体の可能性を強調しています.
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