Journal of Fluorescence

, Volume 21, Issue 4, pp 1779–1787 | Cite as

Push-Pull Fluorophores Based on Imidazole-4,5-dicarbonitrile: A Comparison of Spectral Properties in Solution and Polymer Matrices

  • Martin Danko
  • Pavol Hrdlovič
  • Jiří Kulhánek
  • Filip Bureš
Original Paper


Spectral properties of novel type of fluorophores consist of a π-conjugated system end-capped with an electron-donating N,N-dimethylaminophenyl group and an electron-withdrawing imidazole-4,5-dicarbonitrile moiety were examined. An additional π-linker separating these two structural units comprises simple bond (B1P), phenyl (B2B), styryl (B3S) and ethynylphenyl (B4A) moieties. The absorption and fluorescence spectra were taken in cyclohexane, chloroform, acetonitrile, methanol and in polymer matrices such as polystyrene, poly(methyl methacrylate) and poly(vinylchloride). The longest-wavelength absorption band was observed in the range of 300 to 400 nm. Intense fluorescence with quantum yields of 0.2 to 1.0 was observed in cyclohexane, chloroform and in polymer matrices within the range of 380 to 500 nm. The fluorescence was strongly quenched in neat acetonitrile and methanol. The fluorescence lifetimes are in the range of 1–4 ns for all measured fluorophores. The large Stokes shift (4,000 to 8,000 cm−1) indicates a large difference in the spatial arrangement of the chromophore in the absorbing and the emitting states. The observed fluorescence of all fluorophores in chloroform was quenched by 1-oxo-2,2,6,6-tetramethyl-4-hydroxy piperidine by the diffusion-controlled bimolecular rate (cca 2 × 1010 L mol−1 s−1). Polar solvents such as acetonitrile and methanol quenched the fluorescence as well but probably via a different mechanism.


Fluorescence Push-pull Imidazol-3,4-dicarbonitrile Polymer matrices 



M. Danko and P. Hrdlovic thank grant agency VEGA for support of the project 2/0097/09. J. Kulhanek and F. Bures thank to the Czech Science Foundation (203/08/0076) and the Ministry of Education, Youth and Sport of the Czech Republic (MSM 0021627501).

Supplementary material

10895_2011_872_MOESM1_ESM.doc (518 kb)
Supplement Fig. 1S Absorption and fluorescence spectra of B2B in chloroform (CHCl3), cyclohexane (Cy) and methanol (MeOH) at 10−5 mol L−1 and PVC at 0.002 mol kg−1. (DOC 517 kb)
10895_2011_872_MOESM2_ESM.doc (542 kb)
Supplement Fig. 2S Absorption and fluorescence spectra of B3S in chloroform (CHCl3), cyclohexane (Cy) and acetonitrile (Ac) at 10−5 mol L−1 and PVC at 0.002 mol kg−1. (DOC 542 kb)
10895_2011_872_MOESM3_ESM.doc (503 kb)
Supplement Fig. 3S Absorption and fluorescence spectra of B4A in chloroform (CHCl3), cyclohexane (Cy) and methanol (MeOH) at 10−5 mol L−1 and PS at 0.002 mol kg−1. (DOC 503 kb)
10895_2011_872_MOESM4_ESM.doc (82 kb)
Supplement Fig. 4S Stern-Volmer plot fluorescence quench for compound B3S in chloroform caused by 2,4-dinitrotoluene. After correction to screening effect KSV = 40.5 L mol−1, A: 0.929, R: 0.920. (DOC 82 kb)
10895_2011_872_MOESM5_ESM.doc (104 kb)
Supplement Fig. 5S Effects of addition of methanol (MeOH) and acetonitrile (Ac) on the fluorescence of B3S and B4A in chloroform. (DOC 103 kb)
10895_2011_872_MOESM6_ESM.doc (90 kb)
Supplement Fig. 6S Fluorescence maxima shift for B2B in chloroform upon addition of methanol (MeOH) and acetonitril (Ac). (DOC 90 kb)
10895_2011_872_MOESM7_ESM.doc (90 kb)
Supplement Fig. 7S Fluorescence maxima shift for B3S in chloroform upon addition of methanol (MeOH) and acetonitril (Ac). (DOC 89 kb)
10895_2011_872_MOESM8_ESM.doc (92 kb)
Supplement Fig. 8S Fluorescence maxima shift for B4A in chloroform upon addition of methanol (MeOH) and acetonitril (Ac). (DOC 92 kb)


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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  • Martin Danko
    • 1
  • Pavol Hrdlovič
    • 1
  • Jiří Kulhánek
    • 2
  • Filip Bureš
    • 2
  1. 1.Department of Photochemistry of Polymers Slovak Academy of SciencesPolymer Institute, Center of Excellence GLYCOMEDBratislavaSlovakia
  2. 2.Institute of Organic Chemistry and Technology, Faculty of Chemical TechnologyUniversity of PardubicePardubiceCzech Republic

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