稳定于室温的E,Z-二二:它们的异构化,协调和循环添加化学
Jieli Lin1, Shihua Liu1, Jie Zhang1
1LIFM, IGCME, School of Chemistry, Sun Yat-Sen University Guangzhou 510006 China lizhsh6@mail.sysu.edu.cn.
Chemical science
|October 13, 2023
概括
研究人员分离和表征了N-异环乙烯 (NHV) 替代型二烯的E和Z异构体. 这些异构体在协调和循环添加反应中表现出可逆光异构化和明显的反应性,为重主要组元素化学提供了新的见解.
科学领域:
- 有机金属化学 有机金属化学
- 主群 化学 化学
- 一个异构体的异构体.
背景情况:
- 对于物理性质和反应性来说,E/Z异构是至关重要的.
- 关于重主要组元素同体的研究是有限的.
- N-异环碳 (NHCs) 是一个多功能联体.
研究的目的:
- 隔离和描述NHV替代二二的E和Z异构体.
- 为了研究这些二二异构体的异构化行为和反应性.
- 探索它们的协调化学与黄金和循环添加反应.
主要方法:
- 隔离和X射线结晶学表征E/Z-二二同体.
- 光化学和热异构化研究.
- 与AuCl和循环添加反应 (Diels-Alder,1,3-双极) 的协调化学.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 成功地分离了NHV替代的二二烯 (E,Z-2b) 的E和Z异构体.
- E-2b在热力学上更稳定,并经历可逆光异构化到Z-2b;Z-2b在热力上恢复到E-2b.
- E,Z-2b 完全形成 Z-二二黄金复合物 [AuCl(η2-Z-2b) ] .
- 这两种异构体都经历循环添加反应,产生具有转位NHV组的产物.
- DFT计算阐明了异构化机制和立体选择性.
结论:
- 这项研究首次分离了NHV替代二二的E/Z异构体.
- 展示了光和热异构化行为,由P=P键旋转驱动.
- 观察到异构体的明显的协调和循环添加反应性.
- DFT计算提供了对异构化和立体选择性反应的机制性见解.
相关概念视频
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