- Design, synthesis and properties of a reactive chromophoric/fluorometric probe for hydrogen peroxide detection
-
As the most important starting material and degradation product of peroxide explosives, H2O2 is considered as a signature compound for peroxide-based explosives. A new probe, (2-(2,6-bis((E)-2-(10-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)anthracen-9-yl)vinyl)-4H-pyran-4-ylidene)malononitrile) (AVPM), for both chromophoric/fluorometric detection of H2O2 was designed and synthesized. AVPM emitted a long wavelength emission from its intramolecular charge transfer (ICT) and hence its absorption was expanded to the visible region. The response rate and sensitivity of AVPM for H2O2 detection were tremendously improved (91% of the fluorescence was quenched within 2 min for H2O2) by adding triethylamine (TEA) into the probe solution. And the solution color changed from yellow to blue. A detection limit down to 17.58 nM is remarkably achieved. These features lead to a new chromophoric/fluorometric probe for H2O2 detection and make it an ideal candidate for chemical detection and analysis in public safety and environmental monitoring.
- Zhang, Yu,Jiao, Zinuo,Xu, Wei,Fu, Yanyan,Zhu, Defeng,Xu, Jiaqiang,He, Qingguo,Cao, Huimin,Cheng, Jiangong
-
-
Read Online
- Emission color tuning with polymer molecular weight for dyes of 4-dicyanomethylene-2-methyl-6-{4-[(2-hydroxyethyl)(methyl)amino]styryl}-4H-pyran
-
A series of novel polylactide (PLA) polymers were synthesized initiated by 4-dicyanomethylene-2-methyl-6-{4-[(2-hydroxyethyl)(methyl)amino]styryl} -4H-pyran (DCM) with Sn(Oct)2 as catalyst. The color and emission of the polymer can be tuned just with polymer molecular weight. A series of novel polylactide (PLA) polymers were synthesized initiated by 4-dicyanomethylene-2- methyl-6-(4-((2-hydroxyethyl)(methyl)amino)styryl)-4H-pyran (DCM) and the color and emission of the polymer can be tuned just with polymer molecular weight. Copyright
- Zhang, Jinfeng,Wu, Jincai
-
-
Read Online
- Tuning optical absorption in pyran derivatives for DSSC
-
Four nobel metal free dyes for application as photosensitizers in DSSC have been synthesized and their chemical-physical properties characterized by UV-vis absorption spectroscopy, cyclic voltammetry and DFT theoretical computations. The dyes are based on a pyran core, functionalized with different electron acceptor groups, symmetrically linked to carbazole electron donor mojeties. The four dyes have different optical absorption properties, affording a range of colors ranging from orange to blue, covering most of the visible spectral region. All the dyes feature high molar extinction coefficient, up to a value of 1.0 × 105 L mol-1 cm-1. The dyes were used as photosensitizers in DSSC and the photovoltaic characterization of these devices was performed under simulated solar radiation. The cell performance is higher for chromophores featuring higher LUMO energies as a consequence of a better electron injection in TiO2 oxide. A maximum power conversion efficiency of 1.9% has been achieved.
- Maglione,Carella,Centore,Fusco,Velardo,Peluso,Colonna,Di Carlo
-
-
Read Online
- A Novel Bat-Shaped Dicyanomethylene-4H-pyran-Functionalized Naphthalimide for Highly Efficient Solution-Processed Multilevel Memory Devices
-
Small-molecule-based multilevel memory devices have attracted increasing attention because of their advantages, such as super-high storage density, fast reading speed, light weight, low energy consumption, and shock resistance. However, the fabrication of small-molecule-based devices always requires expensive vacuum-deposition techniques or high temperatures for spin-coating. Herein, through rational tailoring of a previous molecule, DPCNCANA (4,4′-(6,6′-bis(2-octyl-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinolin-6-yl)-9H,9′H-[3,3′-bicarbazole]-9,9′-diyl)dibenzonitrile), a novel bat-shaped A-D-A-type (A-D-A=acceptor–donor–acceptor) symmetric framework has been successfully synthesized and can be dissolved in common solvents at room temperature. Additionally, it has a low-energy bandgap and dense intramolecular stacking in the film state. The solution-processed memory devices exhibited high-performance nonvolatile multilevel data-storage properties with low switching threshold voltages of about ?1.3 and ?2.7 V, which is beneficial for low power consumption. Our result should prompt the study of highly efficient solution-processed multilevel memory devices in the field of organic electronics.
- Zhang, Qi-Jian,Miao, Shi-Feng,Li, Hua,He, Jing-Hui,Li, Na-Jun,Xu, Qing-Feng,Chen, Dong-Yun,Lu, Jian-Mei
-
-
Read Online
- Design, synthesis and characterization of ferrocene based V-shaped chromophores with modified nonlinear effect
-
In order to prepare D-π-A-π-D analogs have the ability to use in optical applications, 4H-pyran fragment conjugated with two styryl groups and their combination play π-spacer role between donor and acceptor groups. Malononitrile and 1, 3-indandione play as acceptor groups and ferrocene nuclei was chosen as donor group. 1H and 13C NMR, FT-IR and mass spectroscopy and CHN analysis were used to confirm the structure of synthesized compounds. Electrochemical, photochemical and photophysical properties of these compounds were studied. The third order nonlinear refractive index, n2, and nonlinear absorption coefficient, β, of synthesized chromophores were assessed by the open and closed aperture Z-scan measurements, respectively. The quantum chemistry study was performed on synthesized compounds with the DFT approach. The theoretical and experimental results show that these compounds can be considered as candidates to be used in optical applications.
- Teimuri-Mofrad, Reza,Rahimpour, Keshvar,Ghadari, Rahim
-
-
Read Online
- Novel pyran based dyes for application in dye sensitized solar cells
-
A class of novel pyran based chromophores has been synthesized and characterized for what concerns their optical and electrochemical properties. The electronic structures were investigated in details by means of DFT theoretical computations. The molecular structures of the chromophores are based on a pyran core, functionalized with different electron acceptor groups, symmetrically linked to phenothiazine electron donor moieties. The dyes have different optical absorption properties, affording a set of colors ranging from orange to blue, covering most of the visible spectral region and they are characterized by high molar extinction coefficient, up to a value of 6.4·104 cm-1 M-1. The dyes were used as photosensitizers in DSSC and the photovoltaic characterization of these devices was performed under simulated solar radiation. A maximum efficiency of 2.82% has been achieved. The most promising device underwent an accelerated ageing test, performed at 85 °C for 50 days: no variation of the main electrical parameters of the DSSC was observed during the test, indicating an excellent stability for devices based on this class of photosensitizers.
- Maglione,Carella,Carbonara,Centore,Fusco,Velardo,Peluso,Colonna,Lanuti,Di Carlo
-
-
Read Online
- Two-photon pumped emission of polymeric thin film doped with dicyanopyranone derivative
-
Two-photon pumped up-conversion emission of polymeric thin film doped with an organic fluorophore dye (1) is described. It is found that 1 exhibits strong two-photon pumped up-conversion emission in polymeric thin film, and the mechanism shows that the up-conversion emission results from efficient two-photon absorption.
- Gao, Zheng,Chen, Yi
-
-
Read Online
- A red-emitting fluorescent probe with large Stokes shift for real-time tracking of cysteine over glutathione and homocysteine in living cells
-
Fluorescent probes with high quality for highly selective detection of cysteine (Cys) are still urgently in demand because of the indispensable roles Cys plays in the biological systems. Herein, a red-emitting fluorescent probe CP was developed for the highly selective detection of Cys over glutathione (GSH) and homocysteine (Hcy) by incorporating acryloyl group as the recognition unit into the 2-(2-(4-hydroxystyryl)-6-methyl-4H-pyran-4-ylidene) malononitrile (P-OH) fluorophore which is characterized by red emission, noteworthy Stokes shift, and appreciable photostability. Basically, CP demonstrated appreciable sensing performance toward Cys including short response time of 4 min, high sensitivity with approximately 147-fold emission enhancement, low detection limit of 41.696 nM, and good selectivity both in the solution and living cells, indicating its promising potential of visualizing Cys in biological systems.
- Qian, Ming,Zhang, Liuwei,Wang, Jingyun,Peng, Xiaojun
-
-
Read Online
- Near-infrared luminous triphenylamine derivative fluorescent molecule as well as preparation method and application thereof
-
The invention provides a near-infrared luminous triphenylamine derivative fluorescent molecule as well as a preparation method and application thereof. The structural formula of the triphenylamine derivative fluorescent molecule is shown as a formula I which is described in the specification. The near-infrared fluorescent molecule has relatively large Stokes displacement and near-infrared fluorescence emission signals; and besides, the preparation method of the molecule is simple and high in designability, can effectively guide the design and synthesis of near-infrared fluorescent functional molecule, and has important application prospects in the field of disease diagnosis and treatment. In the formula I, X is as shown in the specification.
- -
-
Paragraph 0062-0067; 0080-0083; 0096-0099; 0112-0115
(2021/05/19)
-
- 4-cyano-7, 8-dihydroisoquinoline derivative as well as preparation method and application thereof
-
The invention relates to the technical field of organic synthesis, in particular to a 4-cyano-7, 8-dihydroisoquinoline derivative as well as a preparation method and application thereof. According to the invention, symmetric and asymmetric dicyanomethylene-4H-pyran derivatives and secondary amine are used as raw materials, and a series of 4-cyano-7, 8-dihydroisoquinoline derivatives are prepared through ring opening and continuous ring closing reactions; and the reaction has the advantages of easily available raw materials, mild reaction conditions, wide substrate range, high yield and the like, is simple to operate, and avoids the defects of tedious steps, harsh reaction conditions, use of toxic and expensive metal catalysts and the like in conventional isoquinoline compound construction. The preparation method provides new possibilities for design and synthesis of isoquinoline molecules and application of the isoquinoline molecules in solid-state fluorescent materials.
- -
-
Paragraph 0058
(2021/05/05)
-
- Diphenylamino-based organic bis-heterocyclic near-infrared fluorescent probe, preparation method and application thereof
-
The invention relates to a diphenylamino-based organic bis-heterocyclic near-infrared fluorescent probe, which has a structural formula I shown as the specification. The near-infrared fluorescent probe provided by the invention has strong emission in a near-infrared wavelength region, and has high photo-thermal properties and chemical stability. The near-infrared fluorescent probe provided by theinvention is simple in preparation method, high in fluorescence quantum yield and large in Stokes shift, and has important application prospects in development of near-infrared fluorescent probes andbioluminescence imaging. Specifically, X is O or S.
- -
-
Paragraph 0058-0063; 0074-0076
(2020/10/04)
-
- Carbazolyl-based organic double-heterocyclic near-infrared fluorescent probe as well as preparation method and application thereof
-
The invention relates to a carbazolyl-based organic double-heterocyclic near-infrared fluorescent probe, which has a structural formula I shown in the specification. The near-infrared fluorescent probe has strong emission in a near-infrared wavelength region, and has high photo-thermal property and chemical stability. The near-infrared fluorescent probe is simple in preparation method, high in fluorescence quantum yield and large in Stokes shift, and has important application prospects in development of near-infrared fluorescent probes and bioluminescence imaging, wherein X is O or S.
- -
-
Paragraph 0059; 0061-0064
(2020/12/05)
-
- Dicyanomethylene-4H-pyran derivatives as well as preparation method and application thereof
-
The invention particularly relates to dicyanomethylene-4H-pyran derivatives as well as a preparation method and an application thereof. The preparation method of the dicyanomethylene-4H-pyran derivatives comprises the following steps: (1) 2,6-dimethyl-4H-pyran-4-one 1 as a starting material is subjected to an addition-elimination reaction with malononitrile, and an intermediate 2 is obtained; (2) the intermediate 2 is subjected to an addition-elimination reaction with indolal with different alkyl chains, and the dicyanomethylene-4H-pyran derivatives are obtained. Indole structural units with different alkyl groups and dicyanomethylene-4H-pyran structural units are introduced into the field of organic solid luminescent materials, novel piezoluminescence color change materials are developed, and the derivatives play an important role in the field of photoelectricity. The provided method adopts a simple synthesis process, purification is easy, and the synthesized piezoluminescence materials are quite applicable to various fields of preparation of pressure sensors, anti-counterfeiting trademarks and the like and have good scientific research value and industrialized application potential.
- -
-
Paragraph 0013; 0073-0078; 0095-0100; 0122-0127; 0149-0154
(2017/12/27)
-
- Mechanochromic and acidochromic response of 4H-pyran derivatives with aggregation-induced emission properties
-
Several 1- and 2-position naphthylethylene-substituted 4H-pyran derivatives comprising two different end groups were synthesized. These two pairs of positional isomers with aggregation-induced emission properties exhibit different stimuli-responsive solid-state fluorescent properties. Both the linking position of the naphthylethylene and the electron-withdrawing end group have a significant impact on the mechanochromic properties of the compounds, whereas, the acidochromic properties are only related to the latter. The transformation between amorphous and crystalline states accounts for the mechanochromic properties and is attributed to loose molecular packing with weak intermolecular interactions, as revealed by crystallographic data. The reversible acidochromic properties are mainly ascribed to protonation/deprotonation of the carbonyl group, which is confirmed by 1H NMR experiments. Additionally, because the emission of these 4H-pyran derivatives in solid state can be tuned by external stimuli, several molecular logic gates were established by using appropriate stimuli operations as the inputs and fluorescent colors as the outputs.
- Zhou, Yibin,Liu, Yanze,Guo, Yang,Liu, Miaochang,Chen, Jiuxi,Huang, Xiaobo,Gao, Wenxia,Ding, Jinchang,Cheng, Yixiang,Wu, Huayue
-
p. 428 - 440
(2017/03/11)
-
- Mechanofluorochromic properties of fluorescent molecules based on a dicyanomethylene-4: H -pyran and indole isomer containing different alkyl chains via an alkene module
-
A series of 3-, 4-, and 5-position indole-substituted dicyanomethylene-4H-pyran (I3PM, I4PM, and I5PM) derivatives with different alkyl chains were synthesized and their mechanofluorochromic (MFC) properties were investigated. Compared with the alkyl chains, the isomerization of the indole unit plays a more important role in regulating the MFC properties of these compounds. The increase of the alkyl chain length and the isomerization of the alkyl chain are favorable to the effective mechanofluorochromism of the I3PM derivatives, however, the former exhibits the opposite effect on that of the I4PM derivatives. The opposite alkyl length-dependent MFC behavior is closely related to the degree of distortion of the molecular conformation, namely the more twisted the molecular conformation, the more pronounced the MFC phenomenon. In particular, the introduction of the alkyl chains is completely detrimental to the MFC properties of the I5PM derivatives. X-Ray diffraction experiments indicate that the MFC properties of some of these compounds should be mainly attributed to the transformation from a crystalline state to an amorphous state because the weak intermolecular interactions and loose molecular packing modes in their solid-state samples can be easily damaged under external force stimuli as revealed by the single crystal X-ray diffraction analysis.
- Qian, Lebin,Zhou, Yibin,Liu, Miaochang,Huang, Xiaobo,Wu, Ge,Gao, Wenxia,Ding, Jinchang,Wu, Huayue
-
p. 42180 - 42191
(2017/09/12)
-
- Polymorphism and mechanochromism of N -alkylated 1,4-dihydropyridine derivatives containing different electron-withdrawing end groups
-
Organic compounds exhibiting polymorphic and/or mechanochromic (MC) properties are promising for applications in multiple areas. However, the design strategy for such compounds is not very clear. Herein, several series of N-alkylated 1,4-dihydropyridine (DHP) derivatives incorporating different electron-withdrawing end groups were synthesized and compared. The electron-withdrawing groups were responsible for their polymorphic and MC properties. Additionally, a number of polymorphs of these DHP derivatives showed a decreasing trend as length of the alkyl chain increased, indicating that a longer alkyl chain was not conducive to formation of the polymorphs. Although differences in emissions of the polymorphs were mainly attributed to their different intermolecular interactions and molecular packing patterns, a subtle difference in the distances of their intermolecular interactions could also be a key factor in the formation of specific polymorphs. Different polymorphs of DHP derivatives could be interconverted by a simple recrystallization process with a specific solvent or through the application of pressure and vapor stimuli. Additionally, the MC properties of these DHP derivatives were ascribed to a phase transition between different crystalline states, instead of the more common transformation between crystalline and amorphous states.
- Lei, Yunxiang,Zhou, Yibin,Qian, Lebin,Wang, Yuxiang,Liu, Miaochang,Huang, Xiaobo,Wu, Ge,Wu, Huayue,Ding, Jinchang,Cheng, Yixiang
-
supporting information
p. 5183 - 5192
(2017/07/11)
-
- A dihydropyridine derivative and its synthesis and use
-
The invention relates to a dihydropyridine derivative, and a synthesizing method and application thereof. Through the usage of the specific operating steps and solvents, the dihydropyridine derivative is found to be capable of emitting strong fluorescent light under the condition of aggregation or in a solid state, so that the dihydropyridine derivative is an excellent aggregation, induction and light emission material, and the dihydropyridine derivative has a good application prospect in the fields of fluorescence sensors, biomarkers, fluorescence imaging, organic luminescent devices and the like. The synthesizing method comprises the following steps: using pyrone compounds as starting materials, and successively reacting with methylene cyanide, amine and aldehyde compounds, so as to obtain dihydropyridine derivative. According to the invention, the productivity is good, the processing is simple, and a good scientific research value can be realized.
- -
-
Paragraph 0057-0059
(2018/02/04)
-
- Piezochromism, acidochromism, solvent-induced emission changes and cell imaging of D-π-A 1,4-dihydropyridine derivatives with aggregation-induced emission properties
-
Three D-π-A 1,4-dihydropyridine derivatives with aggregation-induced emission characteristics were synthesized. The molecules comprise of a 4-(dimethylamino)styryl group as the electron donor group and different end groups, dicyanomethylene, vinylcyanoacetate, and 2-methylene-1H-indene-1,3(2H)-dione, as the electron acceptor, respectively. These target compounds display different stimulus-responsive fluorescent properties in the solid state. The original samples with the dicyanomethylene and vinylcyanoacetate groups do not show fluorescence color changes in response to external force stimuli, whereas the compound containing the 2-methylene-1H-indene-1,3(2H)-dione unit exhibits reversible piezochromism and solvent-induced emission changes due to the transformation between the crystalline and amorphous states, which can be ascribed to their different molecular stacking mode in the solid state. Furthermore, these compounds show different acid/base-induced solid-state fluorescence switching properties due to the different sites of the protonation. Additionally, all of the derivatives can be fabricated into biocompatible fluorescent nanoparticles and used for MCF-7 cell imaging.
- Lei, Yunxiang,Yang, Dongliang,Hua, Huaijie,Dai, Chunhui,Wang, Lianhui,Liu, Miaochang,Huang, Xiaobo,Guo, Yang,Cheng, Yixiang,Wu, Huayue
-
p. 261 - 272
(2016/07/06)
-
- Rational design of novel near-infrared fluorescent DCM derivatives and their application in bioimaging
-
The development of innovative strategies for high-performance near-infrared (NIR) fluorescent materials is in urgent demand for bioimaging. By replacing the stronger electron-withdrawing groups or extending the π-conjugated system, novel NIR fluorescent materials of DCM analogues have been developed, along with several striking characteristics: bright NIR fluorescence over 700 nm, large Stokes shift and good photo-stability. It is demonstrated that introducing a stronger electron-withdrawing unit to the acceptor moiety of DCM analogues is a favourably efficient strategy to tune and prolong the emission wavelength into the NIR region with a large Stokes shift. In comparison with the commercial NIR dye ICG, S-DCM-N and S-DCM-P display excellent photostability and low photobleaching. The large Stokes Shift and NIR fluorescence channel of S-DCM-N and S-DCM-P are very favourable for fluorescence labelling with a high signal-to-noise ratio in living species.
- Wang, Xiaohang,Guo, Zhiqian,Zhu, Shiqin,Liu, Yajing,Shi, Ping,Tian, He,Zhu, Wei-Hong
-
p. 4683 - 4689
(2016/07/19)
-
- Biocompatible nanoparticles with aggregation-induced emission characteristics as far-red/near-infrared fluorescent bioprobes for in vitro and in vivo imaging applications
-
Light emission of 2-(2,6-bis((E)-4-(diphenylamino)styryl)-4H-pyran-4- ylidene)malononitrile (TPA-DCM) is weakened by aggregate formation. Attaching tetraphenylethene (TPE) units as terminals to TPA-DCM dramatically changes its emission behavior: the resulting fluorogen, 2-(2,6-bis((E)-4-(phenyl(4′- (1,2,2-triphenylvinyl)-[1,1′-biphenyl]-4-yl)amino)styryl) -4H-pyran-4-ylidene)malononitrile (TPE-TPA-DCM), is more emissive in the aggregate state, showing the novel phenomenon of aggregation-induced emission (AIE). Formulation of TPE-TPA-DCM using bovine serum albumin (BSA) as the polymer matrix yields uniformly sized protein nanoparticles (NPs) with high brightness and low cytotoxicity. Applications of the fluorogen-loaded BSA NPs for in vitro and in vivo far-red/near-infrared (FR/NIR) bioimaging are successfully demonstrated using MCF-7 breast-cancer cells and a murine hepatoma-22 (H22)-tumor-bearing mouse model, respectively. The AIE-active fluorogen-loaded BSA NPs show an excellent cancer cell uptake and a prominent tumor-targeting ability in vivo due to the enhanced permeability and retention effect. Encapsulation of far-red/near-infrared luminogens with aggregation-induced emission (AIE) characteristics in a bovine serum albumin (BSA) matrix yields nanoparticles (NPs) with uniform size, high brightness, and low cytotoxicity. Applications of these AIE-active NPs for in vitro and in vivo fluorescence imaging are demonstrated using MCF-7 breast-cancer cells and a murine hepatic H22-tumor-bearing mouse model, respectively. Copyright
- Qin, Wei,Ding, Dan,Liu, Jianzhao,Yuan, Wang Zhang,Hu, Yong,Liu, Bin,Tang, Ben Zhong
-
scheme or table
p. 771 - 779
(2012/06/30)
-
- Investigation of 1H NMR chemical shifts of organic dye with hydrogen bonds and ring currents
-
The 1H NMR chemical shifts were theoretically computed for the organic dyes 2-(2,6-dimethyl-4H-pyran-4-ylidene)-malononitrile (1), cyano-(2,6-dimethyl-4H-pyran-4-ylidene)-acetic acid methyl ester (2), 2-(2,6-bis(4-(dimethylamino)styryl)-4H-pyran-4-ylidene)-malononitrile (3), and methyl 2-(2,6-bis(4-(dimethylamino)styryl)-4H-pyran-4-ylidene)-2-cyanoacetate (4) at the GIAO/B3LYP/6-311++G(d,p)//B3LYP/6-311++G(d,p) level of theory. Moreover, the intramolecular rotational barriers of the molecules were calculated to evaluate the internal flexibility with respect to the torsional degrees of freedom, and the nuclear-independent chemical shifts (NICS) were employed to analyze the ring currents. The difference was explained in terms of intramolecular hydrogen bonds and ring currents of the molecules. The 1H NMR spectra were reproduced by experiments for the comparison with computationally constructed data. Our results suggest a good guideline in interpreting 1H NMR chemical shifts using computational methods and furthermore a reliable perspective for designing molecular structures.
- Park, Sung Soo,Won, Yong Sun,Lee, Woojin,Kim, Jae Hong
-
experimental part
p. 2830 - 2836
(2011/06/25)
-
- Triphenylamine-containing D-A-D molecules with (dicyanomethylene)pyran as an acceptor unit for bulk-heterojunction organic solar cells
-
Two new triphenylamine (TPA)-containing D-A-D molecules with TPA as the donor unit (D), (dicyanomethylene)pyran (PM) as the acceptor unit (A) and thienylenevinylene (TV) or 4-hexyl-thienylenevinylene (HTV) as the conjugated pi-bridge, TPA-TV-PM and TPA-HTV-PM, have been designed and synthesized for solution-processable organic solar cells (OSCs). The optical and electrochemical properties of these linear molecules were studied. The compounds exhibit broad absorption in the visible region with lower HOMO energy levels, which are desirable for application as a donor in organic solar cells. The OSC devices were fabricated by spin-coating the blend solution of the molecules as the donor and PC70BM as the acceptor (1:3, w/w). The power conversion efficiency of the OSCs based on TPA-TV-PM and TPA-HTV-PM reached 2.06% and 2.10%, respectively, under the illumination of AM.1.5, 100 mW cm-2. The Royal Society of Chemistry 2011.
- Zhang, Jing,Wu, Guanglong,He, Chang,Deng, Dan,Li, Yongfang
-
p. 3768 - 3774
(2013/01/10)
-
- DYES, COMPOSITIONS AND RELATED METHODS OF USE
-
Donor-acceptor dyes, compositions, and related methods of use are described herein.
- -
-
Page/Page column 49-50
(2010/06/11)
-
- Synthesis and nonlinear optical properties of linear and Λ-shaped pyranone-based chromophores
-
New, pyranone-based chromophores were synthesized and their (nonlinear) optical properties were measured. The chromophores were prepared by first condensing an electron withdrawing group with pyranone, followed by reaction with an aldehyde-functionalized π-conjugated bridged donor molecule. This approach enables one to easily incorporate the pyranone moiety and to prepare both linear and Λ-shaped chromophores. The (nonlinear) optical properties were measured using femtosecond hyper-Rayleigh scattering. These measurements demonstrated the advantages of this approach.
- Koeckelberghs, Guy,De Groof, Leen,Pérez-Moreno, Javier,Asselberghs, Inge,Clays, Koen,Verbiest, Thierry,Samyn, Celest
-
p. 3772 - 3781
(2008/09/20)
-
- IONIC UV-A SUNSCREENS AND COMPOSITIONS CONTAINING THEM
-
The present invention relates to novel 1,4-dihydropyridine derivatives, to novel cosmetic or dermatological sunscreen compositions containing these derivatives and the use of these derivatives for photoprotecting human skin and/or hair against UV radiation, in particular solar radiation.
- -
-
Page/Page column 31; 32-33
(2010/02/13)
-
- Synthesis and luminescent properties of fluorene copolymers bearing DCM pendants
-
A series of copolymers, poly[(9,9-dioctylfluorene-2,7-diyl) -co-(4-dicyanomethylene-2-methyl-6-[4-(diphenylamino)styryl]-4H-pyran-4′, 4″-diyl], were synthesized by polymerizing 2,7-bis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-9,9-dioctylfluorene with mixtures of 2,7-dibromo-9,9-dioctylfluorene and 4-dicyanomethylene-2-methyl-6-[bis(4′-bromophenyl)amino]styryl]-4H-pyran (a DCM derivative) by the palladium-catalyzed Suzuki coupling reaction. The copolymers were characterized by molecular weight determination, elemental analysis, 1H NMR, FT-IR spectroscopy, DSC, TGA, UV-vis spectroscopy, and photoluminescence (PL) and electroluminescence (EL) spectroscopy. The copolymers showed two absorption peaks at 380 and 485 nm, and the long-wavelength absorption increased with increasing the fraction of the DCM comonomer. The PL spectra of copolymers in chloroform solution displayed emission from both the main chain (420 nm) and DCM units (620 nm). In the solid state, however, PL spectra of copolymers showed only the long wavelength red emission at 620 nm with no trace of emission from the main chain, which implies a facile exciton migration or energy transfer to the lower energy sites from the fluorene part to the DCM part. This results in emission of only the red light originating from the latter segments. A study on time-resolved PL rise and decay of the polymers clearly supports the energy transfer mechanism. Light-emitting diode (LED) devices were fabricated to have the configuration of ITO (indiumtin oxide)/PEDOT/polymer/Li:Al alloy. EL spectra of the devices showed only red emissions as observed in the PL spectra of the polymers' thin films. EL efficiency decreased with increasing DCM contents. When a tris(8-hydroxyquinolinato)aluminum (Alq3) layer was inserted between the emitting polymer layer and the cathode to make the ITO/PEDOT/polymer/Alq3/Li:Al alloy configuration, the device efficiencies became much higher (～10-2%) than those (5 × 10-5-5 × 10-3%) of single-layer devices.
- Cheon, Cheol Hong,Joo, Sung-Hoon,Kim, Kyungkon,Jin, Jung-Il,Shin, Hee-Won,Kim, Yong-Rok
-
p. 6336 - 6345
(2008/02/02)
-
