三重複合体のレドックス化学 (PNP) Co (I)
Michael J Ingleson1, Maren Pink, Hongjun Fan
1Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA.
Journal of the American Chemical Society
|March 12, 2008
まとめ
コバルト複合体の様々な反応剤との反応は,非平面 S = 3/2 種,酸化したリン化合物,コバルト水素を含む多様な製品につながります. DFTの計算はコバルト水素化合物の複合体の形成を合理化するのに役立ちました.
科学分野:
- 有機金属化学 有機金属化学
- 協調化化学について
- 無機合成の無機合成とは
背景:
- ポリデンタートリガンドを持つコバルト複合体は,触媒と材料科学において極めて重要です.
- 異なる酸化状態のコバルト中心の反応性を理解することは,新しい機能的分子を設計する上で鍵となるものです.
- (tBu2PCH2SiMe2) 2N- (PNP) リガンドは,金属中心にユニークな調整環境を提供します.
研究 の 目的:
- コバルト複合体のPNPリガンドとの反応性を調べる.
- 異なる酸化状態とリガンド改変を有する新しいコバルト種を合成し,特徴づけること.
- コバルトセンターとPNPリガンド・スキャフォールドに異なる反応剤の影響を調査する.
主な方法:
- コバルト複合物の合成は,様々な有機および無機反応剤との反応による.
- スペクトロスコーピテクニックとX線結晶学を用いた製品の特徴化.
- 反応経路と製品の安定性を合理化するための密度関数理論 (DFT) 計算.
主要な成果:
- ガルビノキシル基との反応により,非平面 S = 3/2 コバルト (II) 種が生じた.
- アルキルハリドとヨウ素との反応によりコバルト (II) ハリドが生成され,余分なヨウ素はリン酸化を引き起こした.
- H2による水素化によりコバルト二水素が形成され,PhSiH3との反応により,新しいN/SiPhおよびP/Si結合を持つコバルト (((V) 複合体が生じる.
- アジドとダイオキシゲン/イオドシルベンゼンとの反応は,それぞれ窒素挤出,リガンド改変,リン酸化を引き起こした.
結論:
- PNPコバルト複合体は豊富な反応性を発揮し,変異した酸化状態とリガンド構造を持つ多様な製品を形成します.
- 反応は,リン酸化や高価コバルト種の形成などの予期せぬ結果につながる可能性があります.
- DFT計算は,観察された変換の熱力学的実現可能性,特に水素形成について貴重な洞察を提供します.
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