作为水中的单功能和环形反应的伴奏物
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
概括
通过在水溶液中将反应端靠近对方来加速中大环的形成. 这种方法克服了内部应变,提高了二酸盐到循环尿素的循环化速率.
科学领域:
- 超分子化学
- 有机合成
背景情况:
- 形成中型环的循环反应通常由于内部分子应变而缓慢.
- 使用高稀释技术有利于分子内循环,而不是分子间反应,但不会加速循环本身.
研究的目的:
- 研究使用体作为分子宿主来促进中大周期性化合物的形成.
- 通过在水溶液中利用宿主-客体复合来提高循环化速率.
主要方法:
- 应用水溶性体以促进长链二酸盐转化为循环尿素.
- 在二氧化 (D2O) 溶液中进行反应,以利用疏水力来预先组织客分子.
- 使用洞穴内预先组织的折叠形状,使反应端靠近.
主要成果:
- 洞形复合有效地预先将二酸盐客体组织成减少内部应变的构造物.
- 反应端在腔中的距离显著加快了循环反应速率.
- 这种超分子方法成功地克服了与形成中大尺寸环有关的动力障碍.
结论:
- 在水中溶解的体是加速水性介质中具有挑战性的循环反应的有效工具.
- 主体-客体复合策略为合成周期性尿素和潜在的其他中大尺寸环提供了一个有前途的途径.
- 这种方法对远程功能化反应和其他需要受控分子组装的合成过程有影响.
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