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.
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.
Wei
W
Lu
Yuen-Chi
YC
Law
Jie
J
Han
Stephen Sin-Yin
SS
Chui
Dik-Lung
DL
Ma
Nianyong
N
Zhu
Chi-Ming
CM
Che
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