A dicationic organoplatinum(II) complex containing a bridging 2,5-bis-(4-ethynylphenyl)-[1,3,4]oxadiazole ligand behaves as a phosphorescent gelator for organic solvents

Chem Asian J. 2008 Jan 4;3(1):59-69. doi: 10.1002/asia.200700265.

Abstract

A dicationic platinum(II) terpyridyl complex, [(tBu3tpy)Pt(OXD)Pt(tBu3tpy)](PF6)2 (tBu(3)tpy = 4,4',4"-tri-tert-butyl-2,2':6',2"-terpyridyl, OXD = 2,5-bis(4-ethynylphenyl)[1,3,4]oxadiazole) formed phosphorescent organogels in acetonitrile or in a mixture of acetonitrile and alcohol. The structure and properties of these emissive gels were analyzed by polarizing optical and confocal laser scanning microscopy, and by variable-temperature 1H NMR, UV/Vis, and emission spectroscopy. Dry gels were studied by scanning electron microscopy, powder X-ray diffraction (PXRD), and small-angle X-ray scattering (SAXS). SEM images of the dry gel revealed a network of interwoven nanofibers (diameter 12-60 nm, length >5 microm). Intermolecular pi-pi interactions between the [(tBu(3)tpy)PtC[triple bond]C] moieties could be deduced from the variable 1H NMR spectra. The PXRD and SAXS data showed that the assembly of the gelator could be represented by a rectangular 2D lattice of 68 A x 14 A. The ability of the complex to gelate a number of organic solvents is most likely due to intermolecular pi-pi interactions between the [(tBu3tpy)PtC[triple bond]C] moieties.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Crystallography, X-Ray
  • Gels*
  • Ligands
  • Luminescence
  • Microscopy / methods
  • Organoplatinum Compounds / chemistry*
  • Oxadiazoles / chemistry*
  • Solvents / chemistry*
  • Spectrum Analysis / methods

Substances

  • Gels
  • Ligands
  • Organoplatinum Compounds
  • Oxadiazoles
  • Solvents