水中の単一機能および環形成反応のためのチャペロンとしてのキャビタン
Nai-Wei Wu1, Julius Rebek1,2
1Department of Chemistry, Fudan University , 220 Handan Road, Shanghai 200433, China.
Journal of the American Chemical Society
|June 4, 2016
まとめ
カビタンドは,水溶液で反応端を近づけることで,中型から大きなリングの形成を加速します. この方法は,内部ストレスを克服し,ダイソシアネートから循環性尿素へのサイクル化率を高めます.
科学分野:
- 超分子化学
- 有機合成
背景:
- 中規模のリングを形成するサイクライゼーション反応は,内部分子ストレスのためにしばしば遅い.
- 高薄化技術は,分子間反応よりも分子内循環を好むために使用されますが,循環自体を加速しません.
研究 の 目的:
- 中大サイズのサイクル化合物の形成を促進する分子宿主としてカビタンスの使用を調査する.
- 水溶液での宿主-ゲストの複合性を利用して循環速度を向上させる.
主な方法:
- 長い鎖のダイソシアン酸塩を循環尿素に変換するために,水溶性カビタンスを適用する.
- オキシドデュテリウム (D2O) の溶液で反応を行い,ゲスト分子の前組織化のための水害力を利用する.
- カビタンドの内部で 準備された折りたたまれた形状を利用して 反応性終端を近接させる
主要な成果:
- カビタンド複合は,ダイソシアネートゲストを内部ストレスを軽減する形状に効果的に前編成する.
- 洞穴内での反応端の近接は,循環反応の速度を著しく加速する.
- この超分子アプローチは,中型から大型のリングの形成に伴う運動の障壁を克服します.
結論:
- 水溶性カビタンドは,水中での困難なサイクル反応を加速させるのに有効なツールです.
- ホスト-ゲスト複合化戦略は,周期性尿素および潜在的に他の中大サイズのリングを合成するための有望な経路を提供します.
- この方法論は,遠隔機能化反応および制御された分子組立を必要とする他の合成プロセスに影響を及ぼします.
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