ナフトールカップリングは,ガス相における赤外線スペクトロスコピーで監視される
1Department of Organic Chemistry, Charles University in Prague, Hlavova 8, 12843 Prague 2, Czech Republic. roithova@natur.cuni.cz
Journal of the American Chemical Society
|December 4, 2009
まとめ
銅 ((II) 媒介のナフトール結合は,ガス相二核群で発生する. 放射線はC−C結合を誘発し,ケト・エノール・タウトメリゼーションによって駆動され,ビノールが熱外的に形成されます.
科学分野:
- 有機金属化学 有機金属化学
- スペクトロスコーピーは,スペクトロスコーピーを用います.
- コンピューティング・ケミストリー
背景:
- 銅で触媒化された結合反応は,有機合成において不可欠である.
- 分子レベルで反応メカニズムを理解することは,触媒設計において極めて重要です.
- ガス相の研究は,溶媒の影響から解放された反応経路に関するユニークな洞察を提供します.
研究 の 目的:
- 銅 (((II) 媒介ナフトール結合の反応機構を解明する.
- カップリングプロセスにおけるTMEDA (N,N,N,N',N'-テトラメチルエチレンダイアミン) の役割を調査する.
- ガス相に関与する中間種を特徴付けるために.
主な方法:
- 赤外線マルチフォトン解離 (IRMPD) スペクトロスコピーは,孤立した二核群を研究するために使用されました.
- 密度関数理論 (DFT) の計算を使用して,反応経路とエネルギー学をモデル化しました.
- ガス相分離と反応中間物質の特徴づけが達成されました.
主要な成果:
- カップリング反応は,特設的に形成された二核クラスターを通じて進行します: [{1-H) }{2-Cu}{2-Cl}{-TMEDA) {2-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}{-}}{-}{-}{-}{-}{-}{-}}{-}{-}{-}{-}{-}}{-}{-}{-}}{-}{-}{-}
- IRMPDのスペクトルは,クラスタ内の結合されていないナフトーラート亜単位の存在を確認した.
- 放射線はC-C結合反応のトリガーとして特定されました.
- 初期製品のケトエノール・タウトメリゼーションがC−C結合を駆動し,ビノール形成はエクソテルミック (-0.61 eV) である.
- 同様のC-OとO-Oの結合は,内熱性であることが判明しました.
結論:
- この研究は,本物のガス相銅媒介ナフトール結合機構を明らかにした.
- 二核銅クラスターと,その後の放射線照射は,C-C結合形成を開始する鍵です.
- ケトエノールタウトメリゼーションの熱力学的好みは,C-OまたはO-OカップリングよりもC-Cカップリング経路を決定します.
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