ビスシル化ダイアゾメタンの触媒トリメリゼーション
Muhammad Farooq Ibad1, Peter Langer, Fabian Reiß
1Abteilung Anorganische Chemie, Institut für Chemie, Universität Rostock, Albert-Einstein-Straße 3a, D-18059 Rostock, Germany.
Journal of the American Chemical Society
|September 25, 2012
まとめ
トリメチルシリルで置換されたディアゾメタンは,触媒によるイソメリゼーションとトリメリゼーションを経て,新しいピラゾール誘導体を形成します. この研究では,DFT計算を用いた反応機構,動力学,熱力学について詳細に説明します.
科学分野:
- オーガノシリコン化学 化学
- 窒素を含むヘテロサイクル.
- 反応機構の研究は,反応メカニズムの研究である.
背景:
- ビス (((トリメチルシリル) ディアゾメタン ((Me (((3) Si)) (((2) CNN) は,複雑な化学変換の可能性のある前駆体です.
- 触媒は,シライライテッド・ディアゾメタン誘導体の反応性を指示する上で重要な役割を果たします.
研究 の 目的:
- (Me(3) Si) (((2) CNN.CNNのイソメリゼーションとその後のトリメリゼーションを調査する.
- 反応に関与する触媒種を特定し,特徴づけること.
- 反応機構,運動学,熱力学を解明する.
主な方法:
- トリメチルシリルイオンの添加を含む実験研究.
- 中間イソニトリリウムイオン触媒の特徴.
- 機械的および熱力学的分析のための密度関数理論 (DFT) 計算.
主要な成果:
- (Me) 3Si) 2CNNから (Me) 3Si) 2NNCへのイソメリゼーションは, [Me) 3Si] 2+) イオンを加えると観察されました.
- 独特のトリメリゼーション反応により,4-ディアゼニル-3-ヒドラジニルピラゾールのみが得られました.
- イソニトリリウムイオンの触媒的役割, [ ((Me ((3) Si)) ((2) NNC (((SiMe ((3)))) ] ((+)) は確認されました.
結論:
- 反応は3段階のメカニズムを通過する:ディアゾメタンイソメリゼーション,C-CまたはN-Cカップリング,および正式なサイクル添加.
- DFT計算は,反応の運動および熱力学的プロファイルに関する洞察を提供します.
- この研究は,シライライテッドダイアゾメタンからピラゾールを代用する新しい合成経路を明らかにしています.
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