(2-エチニルフェニル) トリアゼンサイクリングの2つの異常で競合するメカニズム:偽コアクト酸対ペリサイクリック反応性
David B Kimball1, Rainer Herges, Michael M Haley
1Department of Chemistry, University of Oregon, Eugene, Oregon 97403-1253, USA.
Journal of the American Chemical Society
|February 21, 2002
まとめ
(2-エチニルフェニル) トライアゼンの高温サイクリングはシナリンを産生し,低温での銅の触媒は独占的にアイソインダゾールを形成し,明確な反応経路を明らかにします.
科学分野:
- 有機化学 オーガニック・ケミストリー
- ヘテロサイクル化学 ヘテロサイクル化学
背景:
- トリアゼンは,有機合成における多用途の前駆体である.
- 機能化されたトライアゼンのサイクリング経路の制御は,多様なヘテロサイクルのスキャフォードにアクセスするために不可欠です.
研究 の 目的:
- 異なる条件下で (2-エチニルフェニル) トリアゼンの反応経路を調査する.
- シノリンとイソインダゾールの形成につながるメカニズムを解明する.
主な方法:
- ODCB.における熱サイクリング.
- 銅 ((I) クロリド触媒による1,2-ジクロロエタンのサイクル化.
- 密度関数理論 (DFT) による計算.
- デウテリウムラベリングの研究.
主要な成果:
- 200°Cでの熱サイクリングによるキノリンの独占的形成.
- 50°CでのCuCl触媒によるイソインダゾールの独占的形成.
- 熱循環における3デヒドロキノリニウムイオンの中間物質の識別.
- イソインダゾール形成におけるカルベンの中間物質の有力な証拠.
結論:
- 反応条件は (2-エチニルフェニル) トリアゼネスのサイクル化結果を決定する.
- 異なったメカニズムは,ペリサイクリックと偽コアクトート移行状態を伴う,それぞれシナリンとアイソインダゾールを導きます.
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