Frontiers in Chemistry (Nov 2019)

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

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

DOI
https://doi.org/10.3389/fchem.2019.00768
Journal volume & issue
Vol. 7

Abstract

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Carbazole based fluorophores 9-butyl-3,6-bis-(phenylethynyl)-9H-carbazole (1) and 9-butyl-3,6-bis-(2-phenyl-o-carborane)-9H-carbazole (2) were synthesized via 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.

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