Tuning Photophysical Properties via Positional Isomerization of the Pyridine Ring in Donor-Acceptor-Structured Aggregation-Induced Emission Luminogens Based on Phenylmethylene Pyridineacetonitrile Derivatives.

Content Provider	Europe PMC
Author	Sun, Haiya Chen, Shuixin Zhong, Aiguo Sun, Rong Jin, Jiajie Yang, Jiahao Liu, Dongzhi Niu, Junfeng Lu, Shengli
Editor	Sulka, Grzegorz D.
Copyright Year	2023
Abstract	A series of aggregation-induced emission (AIE)-featured phenylmethylene pyridineacetonitrile derivatives named o-DBCNPy ((Z)-3-(4-(di-p-tolylamino)phenyl)-2-(pyridin-2-yl)acrylonitrile), m-DBCNPy ((Z)-3-(4-(di-p-tolylamino)phenyl)-2-(pyridin-3-yl)acrylonitrile), and p-DBCNPy ((Z)-3-(4-(di-p-tolylamino)phenyl)-2-(pyridin-4-yl)acrylonitrile) have been synthesized by tuning the substitution position of the pyridine ring. The linkage manner of the pyridine ring had influences on the molecular configuration and conjugation, thus leading to different photophysical properties. The absorption and fluorescence emission peak showed a bathochromic shift when the linking position of the pyridine ring changed from the meta to the ortho and para position. Meanwhile, o-DBCNPy exhibited the highest fluorescence quantum yield of 0.81 and the longest fluorescence lifetime of 7.96 ns as a neat film among all three isomers. Moreover, non-doped organic light-emitting diodes (OLEDs) were assembled in which the molecules acted as the light-emitting layer. Due to the relatively prominent emission properties, the electroluminescence (EL) performance of the o-DBCNPy-based OLED was superior to those of the devices based on the other two isomers with an external quantum efficiency (EQE) of 4.31%. The results indicate that delicate molecular modulation of AIE molecules could endow them with improved photophysical properties, making them potential candidates for organic photoelectronic devices.
Journal	Molecules
Volume Number	28
DOI	10.3390/molecules28073282
PubMed Central reference number	PMC10096500
Issue Number	7
PubMed reference number	37050045
e-ISSN	14203049
Language	English
Publisher	Molecular Diversity Preservation International (MDPI)
Publisher Date	2023-04-06
Access Restriction	Open
Subject Keyword	aggregation-induced emission phenylmethylene pyridineacetonitrile positional isomerization fluorescence emission non-doped organic light-emitting diode
Content Type	Text
Resource Type	Article
Subject	Physical and Theoretical Chemistry Medicine Chemistry Drug Discovery Pharmaceutical Science Analytical Chemistry Molecular Medicine Organic Chemistry