Triplet state homoaromaticity: concept, computational validation and experimental relevance†,Chemical Science

当前位置： X-MOL 学术 › Chem. Sci. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Triplet state homoaromaticity: concept, computational validation and experimental relevance†
Chemical Science ( IF 7.6 ) Pub Date : 2018-02-19 00:00:00 , DOI: 10.1039/c7sc05009g
Kjell Jorner ₁ , Burkhard O Jahn _{1,

2} , Patrick Bultinck ₃ , Henrik Ottosson ₁

Affiliation

Cyclic conjugation that occurs through-space and leads to aromatic properties is called homoaromaticity. Here we formulate the homoaromaticity concept for the triplet excited state (T₁) based on Baird's 4n rule and validate it through extensive quantum-chemical calculations on a range of different species (neutral, cationic and anionic). By comparison to well-known ground state homoaromatic molecules we reveal that five of the investigated compounds show strong T₁ homoaromaticity, four show weak homoaromaticity and two are non-aromatic. Two of the compounds have previously been identified as excited state intermediates in photochemical reactions and our calculations indicate that they are also homoaromatic in the first singlet excited state. Homoaromaticity should therefore have broad implications in photochemistry. We further demonstrate this by computational design of a photomechanical “lever” that is powered by relief of homoantiaromatic destabilization in the first singlet excited state.

中文翻译：

三重态同芳香性：概念、计算验证和实验相关性†

通过空间发生并导致芳香性质的循环共轭被称为同芳香性。在这里，我们根据贝尔德 4 n规则制定了三重激发态 (T ₁ ) 的同芳香性概念，并通过对一系列不同物质（中性、阳离子和阴离子）进行广泛的量子化学计算来验证它。通过与众所周知的基态同芳香族分子进行比较，我们发现五种所研究的化合物显示出强的T ₁同芳香族性，四种显示出弱同芳香族性，两种是非芳香族性。其中两种化合物之前已被鉴定为光化学反应中的激发态中间体，我们的计算表明它们在第一单线态激发态下也是同芳香族的。因此，同芳香性在光化学中应该具有广泛的意义。我们通过光机械“杠杆”的计算设计进一步证明了这一点，该“杠杆”由第一单重激发态同反芳香不稳定的缓解提供动力。

更新日期：2018-02-19

点击分享查看原文

点击收藏

公开下载

阅读更多本刊最新论文本刊介绍/投稿指南11