难以捉摸的七个成员的循环伊米诺乙烯四
Bart Verbraeken1, Jan Hullaert2, Joachim van Guyse1
1Supramolecular Chemistry group, Centre of Macromolecular Chemistry (CMaC), Department of Organic and Macromolecular Chemistry , Ghent University , Krijgslaan 281 S4 , 9000 Ghent , Belgium.
Journal of the American Chemical Society
|December 4, 2018
概括
这项研究报告了第一个七个组成的循环 imino ethers 的合成,纠正了以前的错误识别. 这项研究还比较了它们的聚合活性,揭示了环开放聚合 (CROP) 中显著的环大小效应.
科学领域:
- 有机化学
- 聚合物化学
- 异环化学
背景情况:
- 循环胺基乙烯在催化,制药和聚合中具有价值.
- 虽然五个和六个环 (oxazolines,oxazines) 已被充分研究,但七个环的对应物仍未被研究.
- 之前关于七个成员周期性胺基乙烯的报道可能是错误识别的N-乙化皮罗利丁异构体.
研究的目的:
- 合成和表征七个成员的循环伊米诺乙烯.
- 纠正之前报告的化合物的结构分配.
- 研究环形以太的环形开放聚合 (CROP) 反应性的环形大小影响.
主要方法:
- 合成2--4,5,6,7-四-1,3-氧泽.
- 相关化合物的结构阐明和重新分配.
- 对具有不同甲桥长度的同类循环胺基乙烯的CROP反应性的比较研究.
主要成果:
- 一个七个成员的循环胺基乙烯,2--4,5,6,7-四-1,3-oxazepine的成功合成.
- 纠正先前的文献,确定先前报告的七个环为N-化皮罗利丁异构体.
- 在同类系列中对CROP反应性的显著环大小影响的证明.
结论:
- 现在可以合成七个组成的循环胺基乙烯.
- 准确的结构识别对于理解它们的化学性质至关重要.
- 环大小极大地影响了CROP中的循环伊米诺乙烯的聚合行为.
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