AUTHOR=Jiao Jiemin , Kang Jia-Xin , Ma Yanna , Zhao Qianyi , Li Huizhen , Zhang Jie , Chen Xuenian 

TITLE=Aggregation-Induced Fluorescence of Carbazole and o-Carborane Based Organic Fluorophore

JOURNAL=Frontiers in Chemistry

VOLUME=7

YEAR=2019

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2019.00768

DOI=10.3389/fchem.2019.00768

ISSN=2296-2646

ABSTRACT=<p>Carbazole based fluorophores 9-butyl-3,6-bis-(phenylethynyl)-9H-carbazole (1) and 9-butyl-3,6-bis-(2-phenyl-<italic>o</italic>-carborane)-9H-carbazole (2) were synthesized <italic>via</italic> Sonogashira type cross-coupling reaction and followed by insertion with decaborane. Compound 1 exhibited far more intense fluorescence than 2 in THF solution, while in solid state 2 exerted stronger fluorescence than 1. The fluorescence quenching behavior of 2 in THF solution could be attributed to the intramolecular charge transfer of donor-acceptor system in 2, which was confirmed by electrochemical experiments and DFT calculations. The fluorescence enhancement of 2 in solid state can be ascribed to aggregational induced packing which was evidenced by crystallographic study. In addition, compound 2 showed typical aggregation induced emission (AIE) behavior.</p>