ストレントサイクロファンのマクロサイクル: リングサイズの漸進的な縮小が合成と構造に与える影響
Andrew R Bogdan1, Steven V Jerome, K N Houk
1The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Journal of the American Chemical Society
|December 3, 2011
まとめ
研究者は,新しいストレートサイクロファンのマクロサイクルを合成し,挑戦的な化学空間を探索しました. ストレインエネルギーは,製品比に影響を与え,ストレインされていない分子では見られないユニークな機能群指向を可能にします.
科学分野:
- 有機化学 オーガニック・ケミストリー
- 超分子化学 超分子化学
- 化学合成とは,化学合成というものです.
背景:
- サイクロファンのマクロサイクルは,医薬品化学と材料科学において重要である.
- 小環 (11-14個) サイクロファンを入手することは,合成的に難しい.
- ストレインエネルギーは,マクロサイクルの構造と特性に大きな影響を及ぼします.
研究 の 目的:
- ストレントサイクロファンのマクロサイクルの同類のシリーズ (11-14メンバー) を合成し,特徴づけること.
- マクロサイクルストレインエネルギーと製品分布の関係を合成で調査する.
- 機能性の新しい空間的配置のためのこれらの緊張されたシステムの有用性を探求する.
主な方法:
- 流れ化学における銅触媒アジドアルキンサイクル添加 (CuAAC) マクロサイクリング.
- 構造的決定のためのX線結晶学.
- 張力エネルギーの計算.
主要な成果:
- 11〜14個のサイクロファンのマクロサイクルの成功合成.
- マクロサイクル対ダイマー比は,計算された張力エネルギーと相関する.
- ストレスの増加は,理想的な幾何学から著しい偏差をもたらしました.
- 11基のサイクロファンは,1,4-非置換された1,2,3-トリアゾールで報告された最小のものを表しています.
結論:
- ストレインエネルギーは,マクロサイクライゼーション結果を制御する上で重要な要因です.
- ストレインされたサイクロファンは,化学機能のユニークな空間的方向性を提供します.
- この研究は,採用された方法論で達成可能なリングストレスの限界を定義しています.
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