Enhancing the deep-red/near-infrared fluorescence of higher rylene diimides via the chalcogen-annulation strategy  

作　　者：Kai Chen Xiao Chen Ke Hu Yilun Zhao Yujian Liu Guogang Liu Jinquan Chen Wei Jiang Zhigang Shuai Da-Hui Qu Zhaohui Wang 

机构地区：[1]Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering,Feringa Nobel Prize Scientist Joint Research Center,Frontiers Science Center for Materiobiology and Dynamic Chemistry,Institute of Fine Chemicals,School of Chemistry and Molecular Engineering,East China University of Science and Technology,Shanghai 200237,China [2]Key Laboratory of Organic Optoelectronics and Molecular Engineering,Department of Chemistry,Tsinghua University,Beijing 100084,China [3]State Key Laboratory of Precision Spectroscopy,East China Normal University,500 Dongchuan Road,Shanghai 200241,China

出　　处：《Science China Chemistry》2024年第4期1324-1333,共10页中国科学（化学英文版）

基　　金：financially supported by the National Natural Science Foundation of China(NSFC)(22235005);the National Postdoctoral Program for Innovative Talents(BX20200128);the 69th batch of Chinese postdoctoral general support(2021M691004);Shanghai Municipal Science and Technology Major Project(2018SHZDZX03);the Fundamental Research Funds for the Central Universities;the Programme of Introducing Talents of Discipline to Universities(B16017)。

摘　　要：Deep-red/near-infrared fluorescence is highly suitable for bioimaging owing to its ability to deeply penetrate tissues,organs,and live animals.However,developing organic fluorophores with high deep-red/near-infrared fluorescence quantum yield(Φ_(FL))and fluorescent brightness remain a significant challenge owing to the energy gap law.Herein,we developed a straightforward and effective chalcogen-annulation strategy by introducing O,S and Se into the bay region of TDI and QDI fluorophores,realizing the increase ofΦFLand fluorescent brightness up to 10 times.To our best knowledge,this study potentially stands as the pioneering instance showcasing the anti-heavy-atom effect of chalcogens,and the absoluteΦFL(93%)and fluorescent brightness(128,200 cm^(-1)mol^(-1)L)of Se-TDI is among top deep-red/near-infrared organic fluorophores currently available.The femtosecond transient absorption(fs-TA)measurements show the absence of obvious changes of the excited state lifetime after the introduction of chalcogens in TDI and QDI fluorophores,indicating that intersystem crossing(ISC)can be neglected in TDI and QDI fluorophores.Theoretical calculations further reveal the chalcogen-annulation strategy increase the radiative rates and reduce the reorganization energy of several accepting modes at the ground state in TDI fluorophores,leading to the suppression of internal conversion(IC)processes.Our chalcogen-annulation strategy,which effectively increases the Φ_(FL)and restricts the IC processes,while remaining unaffected by the heavy-atom effect,offers novel insights and theoretical support for the design and synthesis of deep-red/near-infrared organic fluorophores with high Φ_(FL)and fluorescent brightness.

关 键 词：π-extended rylene diimides chalcogen-annulation strategy deep-red/near-infrared fluorescence 

分 类 号：O657.3[理学—分析化学]