由溶剂选择驱动的可逆宏循环到宏循环间转换
Fei Wang1, Xiangling Shi1, Yi Zhang1
1State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, People's Republic of China.
Journal of the American Chemical Society
|May 12, 2023
概括
研究人员开发了一种用于自组装宏循环的新型单合成方法. 溶剂的选择控制了不同大小的宏循环产品的形成,使得 [1 + 1] 和 [2 + 2] 结构之间的可逆互转成为可能.
科学领域:
- 超分子化学
- 有机合成
- 材料科学
背景情况:
- 宏观循环对宏观循环的相互转换提供了多种结构可能性.
- 在不同大小的宏观循环之间实现可控,可逆的相互转换是一个重大挑战.
研究的目的:
- 为自组装的宏循环开发一个简单的单合成.
- 通过溶剂操纵研究宏循环大小和相互转换的控制.
主要方法:
- 在α,α'-连接的寡二甲基和二胺之间发生的凝结反应.
- 使用各种溶剂 (甲醇,乙醇,,DMSO,DMF,MeCN) 来影响产品的分销.
- 宏循环产品的表征 ([1 + 1] 和 [2 + 2] 组合).
主要成果:
- 一个胺桥接的寡二甲基 (3) 和二胺很容易形成 [2 + 2] 宏循环,独立于溶剂.
- 根据溶剂的选择,将3与2,2'-oxybis(ethylamine) (14) 的凝结产生 [1 + 1] 或 [2 + 2] 的宏循环.
- 特定的溶剂 (甲醇,乙醇,) 偏好 [1 + 1] 产品,而其他溶剂 (DMSO,DMF,MeCN) 偏好 [2 + 2] 产品,通常是沉物.
- 通过改变溶剂,由热力学和可溶性因素驱动,可以实现 [1 + 1] 和 [2 + 2] 大循环之间的可逆互转.
结论:
- 已经建立了一种多功能的一合成自组装宏循环的方法.
- 证明了溶剂控制的可逆宏观循环相互转换,为结构多样性提供了新的策略.
- 这些发现强调了热力学和可溶性参数在指导自组装过程中的重要性.
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