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.
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.
Lu
Wei
W
Department of Chemistry, Open Laboratory of Chemical Biology of the Institute of Molecular Technology for Drug Discovery and Synthesis, University of Hong Kong, Pokfulam Road, Hong Kong SAR, China.
Law
Yuen-Chi
YC
Han
Jie
J
Chui
Stephen Sin-Yin
SS
Ma
Dik-Lung
DL
Zhu
Nianyong
N
Che
Chi-Ming
CM
D018360:Crystallography, X-Ray; D005782:Gels; D008024:Ligands; D049449:Luminescence; D008853:Microscopy / Q000379:methods; D009944:Organoplatinum Compounds / Q000737:chemistry*; D010069:Oxadiazoles / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods
D005782:Gels; D008024:Ligands; D009944:Organoplatinum Compounds; D010069:Oxadiazoles; D012997:Solvents