ニッケルのエタ2オルガノアジド複合体と,その変容がダイナトロゲン挤出による末端イミド複合体に変換される
Rory Waterman1, Gregory L Hillhouse
1Gordon Center for Integrative Science, Department of Chemistry, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, USA.
Journal of the American Chemical Society
|August 30, 2008
まとめ
有機アジドのニッケル触媒反応は,安定したアジドクトを生成する. これらの中介物質は,加熱時に二酸化窒素の挤出により,端末型イミド複合体へと容易に変換されます.
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
- アジド化学 アジド化学
背景:
- オルガンニッケル複合体は,有機合成における貴重な触媒である.
- 有機アジドは,窒素を含む化合物の前駆体である.
研究 の 目的:
- 新しいニッケルアジドクトを合成し,特徴づけること.
- イミド複合体の形成に対するこれらのアダクトの反応性を調査する.
主な方法:
- [{dtbpe) Ni]2{eta2-mu-C6H6) が,1-アダマンチラジドおよびメシチラジドと反応する.
- 結果となるアジドクトの分離と結晶学的な特徴付け.
- 分解経路を決定するための熱分解研究.
主要な成果:
- 安定したeta2-有機アジドクト, (dtbpe) Ni(eta2-N3Rは,R=アダマンチルとメシチルの合成と特徴付けに成功しました.
- これらの添加物は,末端のイミド複合体の形成における重要な中間物質として特定されました.
- アジドドクトの軽度な熱分解により,分子内二酸化窒素の損失が観察されました.
結論:
- この研究は,アジドクト経由でニッケル結合末端イミド複合体への新しい経路を示しています.
- この発見は,有機金属系における二酸化窒素挤出のメカニズムについての洞察を提供します.
関連する概念動画
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Nitrous acid is a relatively weak and unstable acid prepared in situ by the reaction of sodium nitrite and cold, dilute hydrochloric acid. In an acidic solution, the nitrous acid undergoes protonation when it loses water to form a nitrosonium ion—an electrophile. Nitrous acid reacts with primary amines to give diazonium salts. The reaction is called diazotization of primary amines.
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Nitrous acid and nitric acids are two types of acids containing nitrogen, among which nitrous acid is weaker than nitric acid. Nitrous acid with a pKa value of 3.37 ionizes in water to give a nitrite ion and the hydronium ion.
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02:50Catalysis
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