ケト・エノール 熱力学 ブレスロウの中間物質
Mathias Paul1, Martin Breugst1, Jörg-Martin Neudörfl1
1Department of Chemistry (Organic Chemistry), University of Cologne , Greinstrasse 4, 50939 Cologne, Germany.
Journal of the American Chemical Society
|February 16, 2016
まとめ
研究者らは,カルベンの触媒の鍵となるブレスロウ中介物のケトオマーを合成した. アルデヒドとN-ヘテロサイクルカルベンの置換作用は,エノールとケトの形態の安定性を影響し,タウトメリゼーションの運動的制限を明らかにします.
科学分野:
- 有機化学
- カタリシス
- 物理化学
背景:
- ブレスロウの中間物質は,カルベンの触媒によるアンポルング反応において極めて重要です.
- 以前の研究では,イミダゾリジニリデンとアルデヒドからアミノエノール種を分離した.
- トリアゾリリデンは,分離可能なエノールが欠け,アルデヒドを含むケトタウトマーのみを生成した.
研究 の 目的:
- イミダゾリジニリデン製のダイアミノエノールを合成する.
- エノール・ケトン・タウトマーの熱力学的安定性を調査する.
- タウトメア形成と安定性に対する置換物の影響を理解する.
主な方法:
- ケトタウトマーの合成
- 15個のエノール-ケトンペアの計算分析
- 熱力学的な計算
主要な成果:
- ダイアミノエノルのケト・タウトマーを 合成した
- 電子を取り除くアルデヒド置換剤はエノール形成を促進する.
- カーベンのN,N'-DippとN,N'-Mes置換物もエノルの形成を促進する.
- ディップ置換は分散相互作用によってエノールタウトメアを安定させる.
結論:
- 置換効果は,エノール-ケトー対称性を決定する.
- 熱力学だけでなく,運動的要因も,タウトメリゼーションを阻害する.
- この研究は,ブレスロウ中間タウトマーの性質と安定性を明らかにする.
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