嵌入曲烯单元中的1,3-二基基:单基与三基状态和平面内芳香度
Yuki Miyazawa1, Zhe Wang1, Misaki Matsumoto1
1Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan.
Journal of the American Chemical Society
|April 26, 2021
概括
曲环烯 (CPP) 的大小决定了嵌入的1,3-二基 (DR) 的基本状态. 较大的DR-CPP表现出三重状态,而较小的则表现出单重状态,显示出尺寸依赖的旋转多重性控制.
科学领域:
- 有机化学
- 材料科学
- 量子化学
背景情况:
- 在基础化学和材料科学中,曲的pi-conjugated分子和开结构是关键.
- 由于其独特的电子性质,1,3-二基基 (DR) 和环烯 (CPP) 具有显著的兴趣.
研究的目的:
- 在曲环烯 (CPP) 结构 (DR- ((n+3) CPP) 中研究 1,3-二基基的化学性质.
- 了解曲率和系统大小如何影响旋转-旋转相互作用,单元/三元状态和平面内芳香度.
- 通过CPP大小来确定基态旋转多重性的控制.
主要方法:
- 量子化学计算可以预测DR-CPP的基本状态.
- 通过其基前体 (AZ-6CPP) 的光化学脱生成DR-6CPP的实验.
- 核独立化学转移 (NICS) 和诱导电流密度 (ACID) 计算以分析平面内芳香度.
主要成果:
- 对于较大的DR-CPP (DR-7CPP,DR-8CPP) 预测的三重地面状态.
- 对于较小的DR-CPP (DR-n+3) 发现单点基态,n=0-3).
- 在DR-6CPP中实验证实了尺寸依赖的旋转多重性控制.
- 在较小的单片状态 (S-DR-4CPP) 中出现平面芳香性,这是由于曲线系统中的同.
结论:
- 根据CPP环的大小,可以调整DR-CPP的基态旋转倍数.
- 曲的CPP可以在单基状态下诱导独特的平面芳香度.
- 这项研究提供了对结构,自旋状态和曲有机分子相互作用的基本见解.
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