(PNPiPr) Re化合物によるアルキル置換ピリジンの芳香的対アリファティックC-H分裂
Oleg V Ozerov1, Maren Pink, Lori A Watson
1Department of Chemistry, Indiana University, Bloomington, Indiana 47405, USA.
Journal of the American Chemical Society
|February 20, 2004
まとめ
PNPリガンドを持つレニウム複合体はアルキルピリジンと反応してピリジル複合体を形成する. これらの複合体は多様な同位体構造を示し,PNPアミド窒素からレニウム中心へのピドネーションを示しています.
科学分野:
- 有機金属化学 有機金属化学
- レーニウム触媒のカタリシス
- 協調化化学について
背景:
- PNPリガンドを含むレニウム複合体は,その触媒活性で知られている.
- リガンドと金属の相互作用を理解することは,新しい触媒の設計に不可欠です.
研究 の 目的:
- アルキルピリジンとの (PNP) Re (((H)) (((4) と (PNP) ReH (((cyclooctyne) の反応性を調査する.
- 生成されたレニウム-ピリジル複合体の構造および電子特性を解明する.
- ピドネーションにおけるPNPアミド窒素の役割を調査する.
主な方法:
- 核磁共振 (NMR) スペクトロスコーピーは,核磁共振 (NMR) スペクトロスコーピーを用います.
- X線微分分析によるX線微分分析
- 密度関数理論 (DFT) の計算
主要な成果:
- アルキルピリジンと (PNP) Re (((H) ((4) の反応により, (PNP) Re (((2) (((エタ (((2) -ピリジル)) とサイクロオクタン,または (PNP) Re ((((エタ ((2) -ピリジル)) (((2) とサイクロオクタンが得られます.
- ビス-ピリジル複合体の構造的に多様な同位体形態が特定され,ピリジルNドネーションはPNPアミドPiドネーションよりも好ましい.
- ステリック阻害とビニルグループの反応性により,カービーンやシグマ-ビニル複合体などのユニークな製品が生成されます.
結論:
- PNPリガンドのアミド窒素は,短いRe-N距離によって証明される,d(4) Re(III) センターにピドネートすることができます.
- ビス-ピリジル・レニウム複合体には,エネルギー的に競合する同位体構造が存在する.
- ピリジンとレニウム複合体の反応性は,ステリックおよび電子的要因に敏感です.
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