Abstract

Two new arylalkyne ligands L1 (D–π–D′ type) and L2 (D–π–A type), and their coordinated Platinum(II) diimine diacetylides 1 (D–π–D′–π–[Pt]–π–D′–π–D type) and 2 (D–π–A–π–[Pt]–π–A–π–D type) were designed and synthesized (where D represents electron donating group and A represents electron accepting group). Photophysical properties measurements indicated that 2 displayed orange-red fluorescence with relatively high fluorescence quantum yield and strong two-photon absorption (2PA) cross-section. The influence of metal on the electronic structure and property was investigated by theoretical calculations and cyclic voltammograms.

Abstract

Abstract

A new coordination compound CuL₂ was synthesized, and its third-order nonlinear optical properties were investigated by Z-scan technique with 2.5 ps laser pulse at 720 nm. The results indicated that the compound CuL₂ exhibited very large nonlinear refraction index n₂ of −4.6 × 10⁻³ cm²/GW and small nonlinear absorption coefficient β of 7.1 cm/GW, giving rise to excellent one-photon figure of merit (FOM), W = 2.9, and two-photon FOM, T = 0.11, respectively, implying that the compound is a promising candidate for application in all-optical switching.

Abstract

Four novel Ir^III and Pt^II complexes with cyclometalated ligands bearing a carbazole framework are prepared and characterized by elemental analysis, NMR spectroscopy, and mass spectrometry. Single-crystal X-ray diffraction studies of complexes 1, 3, and 4 reveal that the 3- or 2-position C atom of the carbazole unit coordinates to the metal center. The difference in the ligation position results in significant shifts in the emission spectra with the changes in wavelength being 84 nm for the Ir complexes and 63 nm for the Pt complexes. The electrochemical behavior and photophysical properties of the complexes are investigated, and correlate well with the results of density functional theory (DFT) calculations. Electroluminescent devices with a configuration of ITO/NPB/CBP:dopant/BCP/AlQ₃/LiF/Al can attain very high efficiencies.

A novel synthetic strategy was developed to prepare polyphosphazenes containing C₆₀ moieties. Thus, the phosphonitrile chloride trimer underwent thermal ring-opening polymerization (ROP) in the presence of C₆₀ molecules to yield the reactive macromolecular intermediate, C₆₀-containing poly(dichlorophosphazene). And then, the other groups could be linked to the phosphazene backbone by nucleophilic substitution reaction of the chlorine atoms in this intermediate to produce a series of C₆₀-containing polyphosphazene. The polymer exhibits good solubility in common organic solvents and is thermally stable.

New polyphosphazenes (P2 and P3) that contain indole-based chromophore and binaphtholyl moieties as side chains are prepared by a new postfunctional strategy. Molecular structural characterization for the high polymers was presented by ¹H-NMR, IR and UV-Visible spectra, gel permeation chromatograply, and differential scanning calorimetry. The glass transition temperature of P2 was determined to be 168°C, higher than those polyphosphazenes reported previously in the literatures. P2 and P3 are thermal stable and easily soluble in high polar solvents. The maximum absorption of P2 in chloroform was at 425 nm and cuts off at about 550 nm, while that of P3 was 393 nm and 500 nm, respectively, which resulted in a wide transparency window. The poled films of P2 and P3 reveal a resonant d₃₃ value of 20 pm/V and 14 pm/V, respectively, by second harmonic generation measurements. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 365–371, 2007

Two new polysiloxanes (P1 and P2) with a high density of sulfonyl-based chromophores were prepared by a new two-step method. Poly[methyl-3-(9-carbazolyl)propyl siloxane] was partially formulated by the standard Vilsmeier reaction, and formyl groups of high reactivity were condensed with cyanoacetylated chromophores; this yielded polysiloxanes P1 and P2 in almost complete conversions. Their structures were verified with ¹H NMR, IR, and ultraviolet–visible spectra. P1 and P2 exhibited good solubility in common organic solvents and were thermally stable. The maximum absorptions appeared at about 452 and 390 nm for P1 and P2, respectively, in tetrahydrofuran; they were blueshifted about 42 and 8 nm, respectively, in comparison with those of the corresponding chromophores with a nitro acceptor and resulted in a wider transparency window. The P1 values of the nonlinear optical coefficient (d₃₃), measured by in situ second harmonic generation, was 16.2 pm/V. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1317–1324, 2005

We have synthesized three new blue-emitting poly(terfluorene) derivatives containing spirobifluorene and electron transport groups (quinoline or oxadiazole). The strategy is to connect the monomers via positions 2 and 2′ of spirobifluorene, which significantly restricts the interchain interaction and effectively adjusts the conjugation length. The incorporation of electron-deficient units (quinoline or oxadiazole) into the positions 7 and 7′ of spirobifluorene tunes the emission band and reduces the lowest unoccupied molecular orbital energy level. Blue electroluminescence with narrow emission was achieved in the devices of ITO/PEDOT/polymer/Ca/Al. The maximum luminances are in the range of 102–235 cd/m² and the maximum photometric efficiencies are in the range of 0.17–0.21 cd/A. All the polymers show good spectral stability, and are promising for use as stable blue-emitting or electron-transport/injection materials in polymeric light-emitting diodes. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4517–4529, 2005

A new polysiloxane (P2), with a high density of the indole-based chromophore and carbazolyl side groups, was prepared. Thus a polysiloxane (P1), with indole and carbazolyl groups as side chains, was first synthesized through a hydrosilylation reaction, and then the post-azo coupling of p-nitrobenzenediazonium fluoroborate toward the indole ring gave the mulifunctional indole-based chromophore-functionalized polysiloxane (P2). Molecular structural characterization for the polymers was determined by ¹H-NMR, IR, and UV–visible spectra, gel permeation chromatography, and differential scanning calorimetry. The polymers were easily soluble in common organic solvents. The poled film of P2 revealed a resonant d₃₃ value of 27 pm/V by second-harmonic generation measurements. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 769–774, 2004

This article reports the detailed synthesis and structural characterization of two new C₆₀-containing poly(ethylene oxide)s by a new postfunctional method. A predesigned amino end-functionalized poly(ethylene oxide) was prepared, and this reactive macromolecular intermediate was reacted with C₆₀ molecules in chlorobenzene to yield the C₆₀-containing poly(ethylene oxide)s. The molecular structures of the polymers were characterized with ¹H-NMR, IR, and ultraviolet–visible spectra. The polymers exhibited good solubility in common organic solvents and water and were stable in air. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 867–870, 2004

Two new approaches were developed to synthesize C₆₀-containing polyphosphazenes. Accordingly, two new reactive macromolecular intermediates (P4 and P8) were obtained from poly(dichlorophosphazene) by the direct nucleophilic substitution reaction. In one approach, a predesigned amimo end–functionalized polyphosphazene (P4) was prepared and then reacted with C₆₀ molecules in chlorobenzene to yield C₆₀-containing polyphosphazene; in the other approach, a polyphosphazene containing 4-methyl phenoxy groups as side chains was first prepared, and then part of the 4-methyl groups were converted to azidomethyl groups (in P8), which reacted with C₆₀ to yield C₆₀-containing polyphosphazene. The polymers were characterized by ¹H NMR, ¹³C NMR, IR, and UV–visible spectra and by gel permeation chromatography. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2877–2885, 2004

The synthesis and structural characterization of a series of novel, fluorinated poly(phthalazinone ether)s containing perfluorophenylene moieties are described. The monomers, 4-(4′-hydroxyaryl)phthalazin-1(2H)-ones (2a–2d), were conveniently and efficiently synthesized from phenols and phthalic anhydride in two steps via 2-(4′-hydroxybenzoyl)benzoic acids, which were first obtained by the Friedel–Crafts reaction in good yields and with high stereoselectivity and were then converted into 2a–2d by fusion with hydrazine. All the polymers were prepared by nucleophilic aromatic substitution (S_NAr) polycondensation between the compounds perfluorobiphenyl and 4-(4′-hydroxyaryl)phthalazin-1(2H)-ones (2a-2d). The resulting fluorinated polymers were readily soluble in common organic solvents (e.g., CHCl₃, tetrahydrofuran, dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, etc.) at room temperature. Their weight-average molecular weights and the polydispersities ranged from (7.96–18.25) × 10³ to 1.31–2.71, respectively. Their glass-transition temperatures varied from 213 to 263 °C. They were all stable up to 390 °C both in air and in argon. The 5% weight-loss temperatures of these polymers in air and argon ranged from 393–487 to 437–509 °C, respectively. Wide-angle X-ray diffraction studies indicated they were all amorphous and could be attributed to the presence of kink nonplanar moiety, phenyl phthalazinone along the polymer backbone. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 925–932, 2004

A new strategy, a post coupling method to develop the polyphosphazene (P2) functionalized with carbazolyl groups and nonlinear optical (NLO) chromophores, has been explored. P2 exhibits good solubility in common organic solvents. The poled film of P2 exhibits a resonant d₃₃ value of 42 pm/V by second harmonic generation (SHG) measurements.

Two new C₆₀-containing polysiloxanes were synthesized by a new postfunctional method. First, the predesigned amimo end-functionalized polysiloxane was prepared, and then the reactive macromolecular intermediate reacted with C₆₀ molecules in chlorobenzene to yield the C₆₀-containing polysiloxanes. Molecular structural characterization for the polymers was presented by ¹H-NMR, IR, and ultraviolet-visible spectra. The polymers exhibited good solubility in common organic solvents and were air stable. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2068–2071, 2003

A new postfunctionalization strategy for developing polyphosphazene functionalized with a high density of highly polar molecules was explored, and the moiety loading was up to 0.84 per unit. A polyphosphazene with N,N-dialkyl-substituted aniline as side chains was first synthesized by a direct substituted reaction, and then post azo coupling of p-nitrobenzenediazonium fluoroborate toward the aniline groups afforded functionalized polyphosphazenes with highly polar molecules. The structural characterization was performed with ¹H-NMR, IR, and ultraviolet–visible spectroscopy and gel permeation chromatography. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2989–2993, 2003

Two types of polysiloxanes, which contain both C₆₀ moieties and carbazolyl groups in the side chains with a difference in the numbers of the reacting site on C₆₀ molecules, were synthesized and their fluorescent properties were studied to distinguish the role of C₆₀ in the luminescent polymers. Our results demonstrated that when C₆₀ moieties are bonded to the polymers as multisubstituents but not linked to the luminescent moieties directly, the luminescence of the resultant polymers were still very strong instead of quenching, even the substituted degree is only 1.01.

A series of new poly (ferrocenylenesilanes) containing carbazole as charge transporting agent and Dispersed Red 1 (DR-1) as second-order nonlinear optical (NLO) chromophore was synthesized. The resulting polymers represent the first example of NLO polymer with ferrocenyl groups in the backbone. This series of polymers was characterized with ¹H NMR, LTV-vis, IR spectroscopies, differential scanning calorimeter (DSC) and gel permeation chromatography (GPC). A preliminary measurement on NLO property of the polymers was carried out with in-situ second-harmonic generation (SHG) measurement.

Two new blue-light-emitting polyphosphazenes (1 and 2) containing carbazolyl groups as side chains were synthesized from a highly reactive macromolecular intermediate by a nucleophilic substitution reaction. Molecular structural characterization for the polymers was presented by ¹H NMR, IR, and ultraviolet–visible spectra, gel permeation chromatography, and differential scanning calorimetry. The polymers exhibited excellent solubility in common organic solvents and were thermally stable. A fluorescence analysis of the two materials in tetrahydrofuran showed a strong blue light emitting. The quantum yields of the polyphosphazenes were 0.55 for 1 and 0.64 for 2, relative to quinoline (in 0.1 N H₂SO₄). An electroluminescent diode was fabricated, and a bright blue light was observed; the maximum external quantum efficiency was about 0.026% at an applied forward voltage of 23 V. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3428–3433, 2001

A novel strategy to develop polysilanes functionalized with a high density of nonlinear optical chromophores has been explored. Thus a polysilane with phenyl and N,N-dialkylsubstituted aniline as pendant groups was synthesized under standard conditions for the Wurtz reductive coupling, and the post azo coupling of p-nitrobenzenediazonium fluoroborate towards the aniline groups afforded a dispersed red (DR) chromophore-functionalized polysilane (P2). The poled film of P2 reveals a resonant d₃₃ value of 19 pm/V by second harmonic generation (SHG) measurements.

A novel series of multifunctional polysiloxanes with photo-refractive properties have been synthesized via a hydrosilylation reaction with 9-allylcarbazole (ACZ) as charge-transporting agent, 1-allyloxyl-2,5-dimethyl-4-(4-nitro-phenylazo)benzene (ADNPAB) as electro-optical chromophore and poly(hydrogenmethylsiloxane). The component concentrations in the polymers can be controlled by different reagent ratios between ACZ and ADNPAB. The structural characterization of the polymers is presented, together with ¹H NMR, IR spectra and elemental analysis.

© 1999 Society of Chemical Industry