コンペティティブC-I対C-CNは,Rh (III) 複合体からの還元性排除である. 選択性は溶媒によって制御される
Moran Feller1, Mark A Iron, Linda J W Shimon
1Department of Organic Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel.
Journal of the American Chemical Society
|October 14, 2008
まとめ
RhIII複合体は,溶媒の極性によって2つの経路で選択的に反応する. プロティック溶媒はアセトニトリル除去を促進し,アプロティック溶媒はメチルヨウ酸化物の除去とイソニトリル形成を促進します.
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
- 反応メカニズム 反応メカニズム
背景:
- RhIII複合体[...]PNP[...]Rh[...]CN[...]CH3][I] (5) は,メチルヨーデッドを[...]PNP[...]Rh[...]CN] (2) に酸化的に加えることで合成される.
- このような複合体の反応性を理解することは,新しい触媒プロセスや材料の開発に不可欠です.
研究 の 目的:
- RhIII複合体の選択反応経路を調査する [(PNP) Rh ((CN) ((CH3)) ][I] (5).
- 反応結果の方向づけにおける溶媒の極性の役割を明らかにする.
- シアノリガンドに対する電愛性の攻撃のメカニズムを理解するために.
主な方法:
- RhIII複合体の合成 [[[PNP]]Rh[[CN]]CH3[[I]] (5). RhIII複合体の合成について
- 様々なアプロティックおよびプロティック溶媒における複合体のアルキルヨウ酸化物との反応.
- スペクトロスコーピテクニックとX線 difraktionを用いた製品の特徴付け.
主要な成果:
- アプロティック溶媒では,メチルヨウ酸化物のC-I還元性除去が起こり,その後,サイアノリガンドに対する電友性の攻撃が起こり,メチルイソニトリルRhI複合体 [(PNP) Rh (((CNCH3) ] [I] (3) を生成する.
- プロティック溶媒では,アセトニトリルのC-C還元性除去が起こり,ヨウ素RhI複合体 [(PNP) RhI] (9) を形成する.
- X線 difraktionによって,サイアノリガンドとプロティック溶媒の間の水素結合が確認され,電愛性の攻撃を阻害しました.
結論:
- 溶媒はRhIII複合体の反応経路を決定し,RhI複合体の異なる産物となる.
- 水素結合相互作用は,シアノリガンドの反応性を調節する上で重要な役割を果たします.
- この研究は,有機金属化学における選択的変異についての洞察を提供します.
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