Issue 3, 2024

Thia[n]helicenes with long persistent phosphorescence

Abstract

Helicenes with persistent luminescence have received relatively little attention, despite their demonstrated highly efficient intersystem crossing (ISC) from the excited singlet to the triplet state. Herein, we designed a series of ortho-fused aromatics by combining dithieno[2,3-b:3′,2′-d]thiophene (DTT) with annulated benzene fragments, denoted as TB[n]H (n = 3–8), to achieve persistent luminescence. Wherein, thia[n]helicenes (n = 5–8) exhibited intense phosphorescence with millisecond-range lifetimes (τp) at 77 K. Particularly interesting was the observation that the odd-numbered ring helicenes displayed longer τp values than their neighboring even-numbered counterparts. Notably, TB[7]H showcased the longest τp of 628 ms. This phenomenon can be attributed to the more favorable ISC channels and stronger spin-orbital coupling (SOC) of old-numbered helicenes than even-numbered ones. Furthermore, both conformers of TB[7]H exhibited significant circularly polarized phosphorescent (CPP) responses, with luminescence dissymmetry factors (glum) of 0.015 and −0.014. These discoveries suggest that thiahelicenes may be a specific class of organic phosphorescent and CPP materials.

Graphical abstract: Thia[n]helicenes with long persistent phosphorescence

Supplementary files

Article information

Article type
Edge Article
Submitted
14 Oct 2023
Accepted
08 Dec 2023
First published
08 Dec 2023
This article is Open Access

All publication charges for this article have been paid for by the Royal Society of Chemistry
Creative Commons BY-NC license

Chem. Sci., 2024,15, 1077-1087

Thia[n]helicenes with long persistent phosphorescence

Z. Sun, W. Xu, S. Qiu, Z. Ma, C. Li, S. Zhang and H. Wang, Chem. Sci., 2024, 15, 1077 DOI: 10.1039/D3SC05480B

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements