Journal of Fluorescence

, Volume 26, Issue 1, pp 323–331 | Cite as

Synthesis, Characterization, Properties and DFT Calculations of 2-(Benzo[b]thiophen-2-yl)pyridine-based Iridium(III) Complexes with Different Ancillary Ligands

  • Gao-Nan Li
  • Yong-Pi Zeng
  • Kai-Xiu Li
  • Hao-Hua Chen
  • Hui Xie
  • Fu-Lin Zhang
  • Guang-Ying Chen
  • Zhi-Gang Niu


A series of new cyclometalated btp-based iridium(III) complexes with three different ancillary ligands, Ir(btp)2(bozp) (3a), Ir(btp)2(btzp) (3b) and Ir(btp)2(izp) (3c) (btp = 2-(benzo[b]thiophen-2-yl)pyridine, bozp =2-(benzo[d]oxazol-2-yl)phenol, btzp =2-(benzo[d]thiazol-2-yl)phenol, izp = 2-(2 H-indazol-2-yl)phenol), have been synthesized and fully characterized. The crystal structure of 3b has been determined by single crystal X-ray diffraction analysis. A comparative study has been carried out for complexes 3a − 3c by UV-vis absorption spectroscopy, photoluminescence spectroscopy, cyclic voltammetry and DFT calculations. This observation illustrates that the substitution of N or S in ancillary ligand can lead to a marked bathochromic shift of absorption and emission wavelengths. The spectroscopic characterisation of these complexes has been complemented by DFT and TD-DFT calculations, supporting the assignment of 3MLCT/3LC to the lowest energy excited state.


Iridium(III) complex 2-(Benzo[b]thiophen-2-yl)pyridine Ancillary ligand Photoluminescence DFT calculation 



This work was supported by the National Natural Science Foundation of China (No. 21501037), the Natural Science Foundation of Hainan Province (No. 20152017), the Science and Research Project of Education Department of Hainan Province (Nos. Hjkj2013-25 and Hnky2015-27) and Hainan Normal University’s Innovation Experiment Program for University Students (No. cxcyxj2015005).

Supplementary material

10895_2015_1718_MOESM1_ESM.pdf (170 kb)
Crystallographic data (excluding structure factors) for the structural analysis have been deposited with the Cambridge Crystallographic Data Center as supplementary publication No. CCDC 1412058 (3b). Copies of the data can be obtained free of charge via (or from The Director, CCDC, 12 Union Road, Cambridge CB2 1EZ, UK, Fax: +44-1223-336-033. E-mail: (PDF 170 kb)


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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Gao-Nan Li
    • 1
  • Yong-Pi Zeng
    • 1
  • Kai-Xiu Li
    • 1
  • Hao-Hua Chen
    • 1
  • Hui Xie
    • 1
  • Fu-Lin Zhang
    • 1
  • Guang-Ying Chen
    • 2
  • Zhi-Gang Niu
    • 1
    • 2
  1. 1.College of Chemistry and Chemical EngineeringHainan Normal UniversityHaikouChina
  2. 2.Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of EducationHainan Normal UniversityHaikouChina

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