Tricarbonylrhenium complexes from 2-pyridyl-1,2,3-triazole ligands bearing a 4-substituted phenyl arm: a combined experimental and theoretical study

Dalton Trans. 2013 May 21;42(19):7019-31. doi: 10.1039/c3dt33071k.

Abstract

Three new pyridyltriazole ligands (named pyta) bearing a 4-substituted phenyl arm (nitro- (2a), chloro- (2b) or aminophenyl (2c) moiety) have been synthesized using a convenient click chemistry strategy. The corresponding tricarbonylrhenium complexes 3a, 3b and 3c were prepared and fully characterized by means of NMR, IR and mass spectrometry, as well as X-ray crystallography for two of them (3a and 3b). The direct connection of a 4-substituted phenyl arm at the N1 position of the triazolyl ring has a significant influence on the geometry of both, the ligands and their corresponding Re-complexes. The dominant structural feature of these complexes concerns the crystal cohesion. Slip-stacked π-π interactions between two molecules of the complex were observed for 3a and 3b probably resulting from the co-planarity of the organic framework. Furthermore, a combined experimental study and DFT calculations showed that the nature of the pendant arm (X = NO2, NH2 or Cl) could affect the electronic properties of the Re-complexes. If the chloro- or aminophenyl moieties unmodified the photo-physical properties of the complexes 3b and 3c, the presence of a nitrophenyl arm for the complex 3a quenched the luminescence, due to a high probability of non-radiative deactivation.

MeSH terms

  • Coordination Complexes / chemical synthesis
  • Coordination Complexes / chemistry*
  • Crystallography, X-Ray
  • Ligands
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Molecular Conformation
  • Quantum Theory
  • Rhenium / chemistry*
  • Triazoles / chemistry*

Substances

  • Coordination Complexes
  • Ligands
  • Triazoles
  • Rhenium