SEARCH

SEARCH BY CITATION

Keywords:

  • acetylides;
  • gels;
  • luminescence;
  • platinum;
  • self-assembly

Abstract

A dicationic platinum(II) terpyridyl complex, [(tBu3tpy)Pt(OXD)Pt(tBu3tpy)](PF6)2 (tBu3tpy=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 μm). Intermolecular π–π interactions between the [(tBu3tpy)PtC≡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 Å × 14 Å. The ability of the complex to gelate a number of organic solvents is most likely due to intermolecular π–π interactions between the [(tBu3tpy)PtC≡C] moieties.