一个pH值激活的配置旋转开关:控制水区中的E/Z同质化
Shainaz M Landge1, Ivan Aprahamian
1Dartmouth College, Department of Chemistry, Hanover, New Hampshire 03755, USA.
Journal of the American Chemical Society
|December 9, 2009
概括
化学家们开发了一种新型的分子开关,使用化物修饰的甲. 这种pH控制的开关可以在E和Z配置之间进行可逆转换,这代表了化学旋转开关的突破.
科学领域:
- 有机化学 有机化学
- 超分子化学 超分子化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 分子开关对于开发先进材料和设备至关重要.
- 现有的分子开关往往缺乏高效和可逆的控制机制.
- 水衍生物已经显示出作为响应性分子系统的潜力.
研究的目的:
- 为了合成和描述一种基于1,2,3-triketone-2-naphthylhydrazone衍生物的新型分子开关.
- 为了研究pH控制的E和Z配置之间的可逆切换.
- 探索异构化的机制及其对环境因素的依赖.
主要方法:
- 合成含有皮里丁的纳夫甲基化.
- 使用三酸进行质子化并切换到Z-H(+) 配置.
- 使用碳酸去质子化和回归E配置.
- 使用核磁共振 (NMR) 谱学进行表征,特别是1H NMR.
主要成果:
- 一个新型的分子开关成功地通过替换一个碳基组与化环在纳非化中合成.
- 该开关展示了由pH控制的高效和可逆的E/Z配置切换.
- 在溶液中,E配置占主导地位 (97%),在酸性处理后在定量上转化为Z-H(+) 形式.
- 观察到 Z 配置是变态稳定的,热平衡回到 E 形式.
- 发现异构化速率取决于溶剂的极性,这表明水环绕C=N键旋转.
结论:
- 这项研究介绍了第一个化学控制,pH触发,配置旋转分子开关.
- 开发的基于水的开关提供了完全,有效和可逆的E / Z异构.
- 这些发现为设计具有可调节性质的先进分子设备铺平了道路.
相关概念视频
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