431898-09-8Relevant articles and documents
Synthesis of novel platinum complex core as a selective Ag+ sensor and its H-bonded tetrads self-assembled with triarylamine dendrimers for electron/energy transfers
Lin, Hong-Cheu,Shellaiah, Muthaiah,Ramakrishnam Raju, Mandapati V.,Singh, Ashutosh,Lin, Hsin-Chieh,Wei, Kung-Hwa
, p. 17463 - 17476 (2014/12/12)
A novel platinum complex PtC with a tri-armed uracil hydrogen-bonded (H-bonded) unit was synthesized via a modular synthetic approach and characterized by 1H, 13C NMR and MALDI-TOF mass spectroscopies. Two H-bonded tetrads, PtC-(TPAD1)3 and PtC-(TPAD2)3, based on a metal core PtC complexed with two generations of triarylamine dendrimers, TPAD1 and TPAD2 (with electron-donating nature), were successfully constructed with improved organic solubility via a classical H-bonded self-assembly approach. Supramolecular H-bonding in solution and solid state was elucidated by 1H NMR titrations, IR spectral studies and time resolved photoluminescence (TRPL) measurements. The electron/energy transfers, as well as the self-assemblies of supramolecular tetrads, were established by UV-Vis and PL titrations and AFM morphological studies. Furthermore, metal complex core PtC showed selective sensitivity towards Ag+ ions through fluorescence turn-off responses without any interference from other common metal ions. The 1:1 binding stoichiometry and complexation mechanism between the probe and Ag+ ion was established by 1H NMR titration. Moreover, PL reversibility of PtC + Ag+ could be achieved on addition of PMDTA.
Investigation of the photophysical and electrochemical properties of alkoxy-substituted arylene-ethynylene/arylene-vinylene hybrid polymers
Egbe, Daniel Ayuk Mbi,Cornelia, Bader,Nowotny, Juergen,Guenther, Wolfgang,Klemm, Elisabeth
, p. 5459 - 5469 (2007/10/03)
High-molecular-weight, soluble and thermostable alkoxy-substituted arylene-ethynylene/arylene-vinylene conjugated polymers, 18 and 14, have been successfully synthesized through the Horner-Wadsworth-Emmons olefination of luminophoric dialdehydes 7 and 9 and bisphosphonate 12 in very good yields. They were characterized through 1H NMR, 13C NMR, IR, and elemental analysis. The investigation of their photophysical and electrochemical properties has been carried out. Although almost identical absorption and emission spectra were obtained in dilute chloroform solution for all polymers 13, the full width at half-maximum (fwhm) value of the emission curves depends on the length of the attached side chains. The presence of anthracenylene units in 14 leads to a red shift of its absorption and emission spectra relative to 13. Strong self-reabsorption after excitation in solution was observed for this polymer. The solid-state photophysical properties of 13 and 14 (photoconductivity, absorption and emission spectra, fluorescence quantum yield, Stokes shift, and fwhm) greatly depend on the nature (linear or branched), length, and location of the grafted alkoxy side groups. Photoconductivity is easily detected in polymers having octadecyloxy chains (13aa, 13ab, 14). Long linear (octadecyl, i.e., 13aa) or short branched (2-ethylhexyl, i.e., 13cc) side chains at position R2 (phenylene-vinylene segment) are necessary to obtain sharp and well-resolved emission spectra accompanied by high fluorescence quantum yields. The quasi-donor (phenylene-vinylene segment)-acceptor (arylene-ethynylene segment) nature of these polymers could explain the great discrepancy between the electrochemical band gap energy, Egec ≈ 1.60 eV, as obtained from the onset values of the redox potentials in cyclic voltammetry and in differential pulse polarography measurements, and the optical band gap energy, Egopt ≈ 2.30 eV, from the absorption spectra.
