o-hydroxybiarylsにおける興奮状態の分子内プロトン転送:二水酸化芳香化合物への新しい経路
1Department of Chemistry, Box 3065, University of Victoria, Victoria, British Columbia, Canada V8W 3V6.
Journal of the American Chemical Society
|January 30, 2003
まとめ
ナフチルフェノールにおける興奮状態の分子内陽子伝達 (ESIPT) は,効率的にダイヒドロベンゾキサンテンを形成する. この反応は,クリーンで高生産性の合成経路を,価値あるベンゾキサンテンの化合物へと提供します.
科学分野:
- 有機化学 オーガニック・ケミストリー
- フォトケミストリー フォトケミストリー
- 合成化学 合成化学とは
背景:
- 興奮状態の分子内プロトン転送 (ESIPT) は,重要な光化学プロセスです.
- ベンゾキサンテンとダイヒドロベンゾキサンテンは,多様な用途を持つ重要なヘテロサイクル化合物です.
研究 の 目的:
- o-(1'-ナフチル) フェノールおよび1-(1'-ナフチル) - 2 - ナフトール系におけるESIPT反応を調査する.
- ESIPTを用いたダイヒドロベンゾキサンテンの新合成経路を確立する.
主な方法:
- ナフチルフェノール誘導体 (化合物3および4) でESIPTを研究した.
- 反応経路を特定するためにデュテリウムラベルを使用した.
- ディヒドロベンゾキサンテンの産物 (化合物5と7) の形成を特徴づけた.
主要な成果:
- フェノールOHからナフチル環の7'-炭素まで,観察された効率的なESIPT.
- キノンメチド中間体によるダイヒドロベンゾキサンテンの効率的な形成 (量子収量0.1-0.2) が達成された.
- 2'-芳香位置で関連するESIPT経路が検出されました.
結論:
- 記述されたESIPT反応は,ベンゾキサンテナとダイヒドロベンゾキサンテナを合成するためのクリーンで効率的で高収量な方法を提供します.
- デウテリウムラベリングは,これらのシステムにおける代替ESIPT経路を確認した.
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