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Suzuki Coupling Reaction (suzuki + coupling_reaction)
Selected AbstractsCyclopalladated Ferrocenylimine: A Highly Effective Catalyst for the Borylation/Suzuki Coupling Reaction.CHEMINFORM, Issue 37 2007Ning Ma Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Monodisperse Nanoparticles of Ni and NiO: Synthesis, Characterization, Self-Assembled Superlattices, and Catalytic Applications in the Suzuki Coupling Reaction,ADVANCED MATERIALS, Issue 4 2005J. Park Monodisperse spherical Ni nanoparticles with diameters of 2 nm, 5 nm, and 7 nm were synthesized from the thermal decomposition of a Ni,oleylamine complex. Ni nanocrystal superlattices were generated via the controlled evaporation of solvent (see Figure). The nanoparticles were successfully used as catalysts for the Suzuki coupling reaction, and were readily oxidized to produce NiO nanoparticles. [source] ChemInform Abstract: Application of a Readily Available and Air-Stable Monophosphine HBF4 Salt for the Suzuki Coupling Reaction of Aryl or 1-Alkenyl Chlorides.CHEMINFORM, Issue 25 2010Bo Lue Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Design and Synthesis of Potential ,-Sheet Nucleators via Suzuki Coupling Reaction.CHEMINFORM, Issue 15 2008Elisa Perissutti Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Supramolecular Reactor in an Aqueous Environment: Aromatic Cross Suzuki Coupling Reaction at Room Temperature.CHEMINFORM, Issue 11 2006Ja-Hyoung Ryu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Highly Efficient Pd/C-Catalyzed Suzuki Coupling Reaction of p -(un)Substituted Phenyl Halide with (p -Substituted phenyl) Boronic AcidCHINESE JOURNAL OF CHEMISTRY, Issue 8 2007Ming-Gang Hu Abstract A highly efficient Pd/C-catalyzed ligandless, heterogeneous Suzuki reaction of p -(un)substituted phenyl halide with (p -substituted phenyl)boronic acid in DMF/H2O solvent in a short reaction time (0.5 h) at 75 °C was developed. The key for such a catalytic system was the addition of 1 equivalent of tetrabutylammonium bromide. A wide variety of substituents can be tolerated and high yields of cross coupling products were achieved. The palladium catalyst can be easily recovered and reused without significantly decreasing its efficiency. [source] "Click" Polymer-Supported Palladium Nanoparticles as Highly Efficient Catalysts for Olefin Hydrogenation and Suzuki Coupling Reactions under Ambient ConditionsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 13 2009Cátia Ornelas Abstract Complexation of palladium(II) acetate [Pd(OAc)2] or dipotassium tetrachloropalladate [K2PdCl4] to "click" polymers functionalized with phenyl, ferrocenyl and sodium sulfonate groups gave polymeric palladium(II)-triazolyl complexes that were reduced to "click" polymer-stabilized palladium nanoparticles (PdNPs). Transmission electron microscopy (TEM) showed that reduction using sodium borohydride (NaBH4) produced PdNPs in the 1,3,nm range of diameters depending on the nature of the functional group, whereas slow reduction using methanol yielded PdNPs in the 22,25,nm range. The most active of these PdNPs (0.01% mol Pd), stabilized by poly(ferrocenyltriazolylmethyl)styrene, catalyzed the hydrogenation of styrene at 25,°C and 1 atm hydrogen, with turnover numbers (TONs) of 200,000. When stabilized by the water-soluble poly(sodium sulfonate-triazolylmethyl)styrene, the PdNPs (0.01% mol Pd) catalyze the Suzuki,Miyaura coupling between iodobenzene (PhI) and phenylboronic acid [PhB(OH)2] in water/ethanol (H2O/EtOH) at 25,°C with TONs of 8,200. This high catalytic activity is comparable to that obtained with "click" dendrimer-stabilized PdNPs under ambient conditions. [source] ChemInform Abstract: An Inexpensive and Highly Stable Palladium(II) Complex for Room Temperature Suzuki Coupling Reactions under Ambient Atmosphere.CHEMINFORM, Issue 31 2009Mengping Guo Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Nafion,Teflon Bimembrane-Supported Palladium Catalysts for Suzuki Coupling Reactions.CHEMINFORM, Issue 16 2008Li Ting Chai Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Synthesis, Characterization, and Applications in Heck and Suzuki Coupling Reactions of Amphiphilic Cyclopalladated Ferrocenylimines.CHEMINFORM, Issue 11 2008Bing Mu Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] The Synthesis of Substituted Phenylpyrimidines via Suzuki Coupling Reactions.CHEMINFORM, Issue 19 2006Thomas J. Delia Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Chelate [2-(Iminoethyl)pyridine N -oxide]metal Complexes , Synthesis and Structural Comparison with Their Chemically Related 2-(Iminoethyl)pyridine-Derived SystemsEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 2 2006Katrin Nienkemper Abstract The N,O-chelate ligands 2-(iminoethyl)pyridine N -oxide (2a) and 2-(iminoethyl)-6-isopropylpyridine N -oxide (2b) were prepared by conventional synthetic routes, the latter involving a variant of the Reissert,Henze reaction. Treatment of 2a with FeCl2 resulted in a deoxygenation reaction of the ligand and formation of the salt [bis{2-(iminoethyl)pyridine}FeCl]+[FeCl4], (18a). In contrast, the reaction of 2a with PdCl2 or CoCl2 cleanly furnished the six-membered chelate [,N,O -2(iminoethyl)pyridine N -oxide]MCl2 complexes (19a, M = Pd) or (20a, M = Co), respectively, which were both characterised by X-ray diffraction. Treatment of 2b with [NiBr2(dme)], followed by crystallisation from THF, gave the complex [(,N,O - 2b)NiBr2(THF)] (21b), which features a distorted trigonal-bipyramidal coordination geometry of the central metal atom. The reaction of 2a with [NiBr2(dme)] gave the structurally related complex [(,N,O - 2a)NiBr2(,O - 2a)] (21a). The N,O-chelate Pd complex 19a was shown to be an active catalyst for the Suzuki coupling reaction. The ligand systems 2a,b and their related 2-(iminoethyl)pyridines 3a,b and a variety of metal complexes of ligands 3 were also prepared and characterised for comparison by X-ray diffraction. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] A New Carbazole-Constructed Hyperbranched Polymer: Convenient One-Pot Synthesis, Hole-Transporting Ability, and Field-Effect Transistor PropertiesADVANCED FUNCTIONAL MATERIALS, Issue 16 2009Zhong'an Li Abstract A new hyperbranched polymer (HB-car), constructed fully by carbazole moieties, is successfully synthesized through a one-pot Suzuki coupling reaction. The resultant polymer is well-characterized, and its hole-transporting ability is studied carefully. The device, in which HB-car is utilized as a hole-transporting layer and tris-(8-hydroxyquinoline) aluminum as an electron-emitting layer as well as electron-transporting layer, gives a much higher efficiency (3.05,cd A,1), than that of a poly(N -vinylcarbazole) based device (2.19,cd A,1) under similar experimental conditions. The remarkable performance is attributed to its low energy barrier and enhanced hole-drifting ability in the HB-car based device. In addition, for the first time, a field-effect transistor (FET) based on the hyperbranched polymer is fabricated, and the organic FET device shows that HB-car is a typical p -type FET material with a saturation mobility of 1,×,10,5,cm2 V,1 s,1, a threshold voltage of ,47.1,V, and an on-to-off current ratio of 103. [source] Monodisperse Nanoparticles of Ni and NiO: Synthesis, Characterization, Self-Assembled Superlattices, and Catalytic Applications in the Suzuki Coupling Reaction,ADVANCED MATERIALS, Issue 4 2005J. Park Monodisperse spherical Ni nanoparticles with diameters of 2 nm, 5 nm, and 7 nm were synthesized from the thermal decomposition of a Ni,oleylamine complex. Ni nanocrystal superlattices were generated via the controlled evaporation of solvent (see Figure). The nanoparticles were successfully used as catalysts for the Suzuki coupling reaction, and were readily oxidized to produce NiO nanoparticles. [source] Air-Stable and Highly Active Dendritic Phosphine Oxide- Stabilized Palladium Nanoparticles: Preparation, Characterization and Applications in the Carbon-Carbon Bond Formation and Hydrogenation ReactionsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2008Lei Wu Abstract Dendrimer-stabilized palladium nanoparticles were formed in the reduction of palldium bis(acetylacetonate) [Pd(acac)2] in the presence of phosphine dendrimer ligands using hydrogen in tetrahydrofuran. The resulting Pd nanoparticles were characterized by TEM, 31P,NMR and 31P MAS NMR. The results indicated that the dendritic phosphine ligands were oxidized to phosphine oxides. These dendrimer-stabilized Pd nanoparticles were demonstrated to be efficient catalysts for Suzuki and Stille coupling reactions and hydrogenations. The dendritic wedges served as a stabilizer for keeping the nanoparticles from aggregating, and as a vehicle for facilitating the separation and/or the recycling of the Pd catalyst. In the case of the Suzuki coupling reaction, these Pd nanoparticles exhibited high catalytic efficiency (TON up to 65,000) and air stability as compared with the commonly used homogeneous catalyst tetrakis(triphenylphosphine)palladium [Pd(PPh3)4]. In addition, the results obtained from the bulky dendritic substrate suggest that the Pd nanoparticles might act as reservoir of catalytically active species, and that the reaction is actually catalyzed by the soluble Pd(0) and/or Pd(II) species leached from the nanoparticle surface. [source] Synthesis and characterization of novel poly(arylenevinylene) derivativeJOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2008Song Se-Yong Abstract The new poly(arylenevinylene) derivative composed naphthalene phenylene vinylene backbone was developed. The theoretical calculation showed that the model compound of the obtained polymer was highly distorted between the stryl and naphthalene units as well as between the backbone and fluorene side units. The polymer was synthesized by the palladium catalyzed Suzuki coupling reaction with 2,6-(1,,2,-ethylborate)-1,5-dihexyloxynaphtalene and 1,2-bis(4,-bromophenyl)-1-(9,,9,-dihexyl-3-fluorenyl)ethene. The structure of the polymer was confirmed by 1H NMR, IR, and elemental analysis. The weight,average molecular weight of the polymer is 29,800 with the polydispersity index of 1.87. The new polymer showed good thermal stability with high Tg of 195°C. The bright blue fluorescence (,max = 475 nm) was observed both in solution and film of new polymer with naphthalene phenylene vinylene backbone. Double layer LED devices with the configuration of ITO/PEDOT/polymer/LiF/Ca/Al showed a turn-on voltage at around 4.5 V, the maximum luminance of 150 cd/m2, and the maximum efficiency of 0.1 cd/A. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] The synthesis and application of 2-acetyl-6-(1-naphthyl)-pyridine oxime as a new ligand for palladium precatalyst in Suzuki coupling reactionJOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 1 2009Yongchang Zhou The synthesis of 2-acetyl-6-(1-naphthyl)-pyridine oxime ligand from 2,6-dibromopyridine and 1-bromo-naphthalene is described, and the new palladium(II) complex used as a Pd(0) precatalyst in the Suzuki cross-coupling reaction was studied. The results showed that the novel naphthalene pyridine oxime complex could serve as an efficient precatalyst. J. Heterocyclic Chem., 46, 116 (2009). [source] Synthesis of thiophene/phenylene co-oligomers.JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 5 2003We report the synthesis of various thiophene/phenylene co-oligomers with a total number of thiophene and benzene (phenylene) rings of 6 to 8. These compounds include a phenyl-capped sexithiophene, a thienyl-capped quaterphenylene, as well as block and alternating co-oligomers. The synthesis is based on either the Suzuki coupling reaction or the direct dimerization coupling. The latter method produces symmetric molecules with an even total ring number. These reaction schemes enabled us to obtain the target compounds in high quality. Although the resulting materials are difficult to dissolve in organic solvents and therefore difficult to identify by usual 1H nmr spectroscopy, they have successfully been identified through Fourier-transform ir spectroscopy. The specific group frequencies of ring-stretching and out-of-plane deformation modes are characteristic of the substitution pattern of the individual thiophene and benzene rings. [source] Synthesis of thiophene/phenylene co-oligomers.JOURNAL OF HETEROCYCLIC CHEMISTRY, Issue 1 2000We report the synthesis of phenyl-capped oligothiophenes via improved synthetic schemes. These schemes are based on the Grignard coupling reaction and enable us to obtain the target compounds at high yields. The resulting materials have been fully characterized through nmr and ir spectroscopies. The ir analysis is particularly useful in characterizing the materials of higher molecular weight, since those materials are difficult to dissolve in organic solvent. We also show an improvement on preparation of halogenated (oligo)thiophenes that are used as intermediates for synthesizing the target compounds. An alternative synthetic route to the phenyl-capped oligothiophenes that utilizes the Suzuki coupling reaction is presented as well. [source] Preparation, morphology, and biolabeling of fluorescent nanoparticles based on conjugated polymers by emulsion polymerizationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2010Rui Wang Abstract Novel nanoparticles based on conjugated polymer with good fluorescent properties were synthesized by Suzuki coupling reaction using certain surfactants as one kind of special emulsion polymerization. The luminescent properties of the prepared nanoparticles could be controlled by selecting different monomers. Without using substances comprising any heavy metal element, these fluorescent nanoparticles show very good biocompatibility with cells, thus showing potential applications in cell biolabeling, drug delivery tracing, organic light-emitting diodes, flat displays, and other areas. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 [source] Relationship between the liquid crystallinity and field-effect-transistor behavior of fluorene,thiophene-based conjugated copolymersJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 16 2006Eunhee Lim Abstract A series of fluorene,thiophene-based semiconducting materials, poly(9,9,-dioctylfluorene- alt -,,,,-bisthieno[3,2- b]thiophene) (F8TT2), poly(9,9,-di(3,6-dioxaheptyl)fluorene- alt -thieno[3,2- b]thiophene) (BDOHF8TT), poly(9,9,-di(3,6-dioxaheptyl)fluorene- alt -bithiophene) (BDOHF8T2), and poly(9,9,-dioctylfluorene- co -bithiophene- co -[4-(2-ethylhexyloxyl)phenyl]diphenylamine) (F8T2TPA), was synthesized through a palladium-catalyzed Suzuki coupling reaction. F8TT2, BDOHF8TT, BDOHF8T2, and F8T2TPA films exhibited photoluminescence maxima at 523, 550, 522, and 559 nm, respectively. Solution-processed field-effect transistors (FETs) fabricated with all the copolymers except F8T2TPA showed p -type organic FET characteristics. Studies of the differential scanning calorimetry scans and FETs of the polymers revealed that more crystalline polymers gave better FET device performance. The greater planarity and rigidity of thieno[3,2- b]thiophene in comparison with bithiophene resulted in higher crystallinity of the polymer backbone, which led to improved FET performance. On the other hand, the random incorporation of the triphenylamine moiety into F8T2TPA caused the polymer chains to lose crystallinity, resulting in an absence of FET characteristics. With this study, we could assess the liquid-crystallinity dependence of the field-effect carrier mobility on organic FETs based on liquid-crystalline copolymers. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4709,4721, 2006 [source] Triphenylamine and Fluorene Based Cationic Conjugated Polyelectrolytes: Synthesis and CharacterizationMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 2 2009Wei Shi Abstract Two kinds of amino-functionized, triphenylamine and fluorene based copolymers, PFT-N and PTFF-N, were synthesized by palladium-catalyzed Suzuki coupling reaction. The corresponding quaternized polyelectrolytes PFT-NBr and PTFF-NBr were obtained through post-polymerization. The quenching behaviors of PFT-NBr and PTFF-NBr in methanol were investigated by the titration of Fe(CN). All of these polymers were investigated as emitting layer in multilayer PLEDs. Devices' performance together with electrochemical properties of these polymers indicate that both of the hole and the electron injection capabilities of them were improved due to the simultaneous introduction of the triphenylamine segment and the aminoalkyl (ammonium) group. [source] Enantio- and Diastereoselective Chemoenzymatic Synthesis of C2-Symmetric Biaryl-Containing DiolsCHEMCATCHEM, Issue 1 2010Edyta Burda Abstract An enantio- and diastereoselective synthesis of C2-symmetric diols bearing a biphenyl-framework has been developed by means of an enzymatic reduction of the corresponding diketones, which were prepared by a Suzuki coupling reaction. Furthermore, a chemoenzymatic one-pot synthesis of a C2-symmetric diol in aqueous media has been realized through combination of the Suzuki coupling reaction and enzymatic reduction. Chiral stereoisomers of the biaryl-containing diols are prepared with diastereomeric ratios in excess of 25:1 and enantiomeric excesses of greater than 99,%. [source] An Atropo-Stereogenic Diphosphane Ligand with a Proximal Cationic Charge: Specific Catalytic Properties of a Palladium Complex ThereofEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 19 2008Nathalie Debono Abstract A class of cationic diphosphane ligands combining phosphane and amidiniophosphane moieties is illustrated on the N -methyl,N -naphthylbenzimidazolium framework. The palladium(II) complex thereof is described and compared to the corresponding complex of the analogous neutral diphosphane. Contrary to first-level expectations, the N2C,P and N2CP,Pd bonds in the cationic diphosphane complex are not longer than those occurring in its neutral counterpart. In the cationic ligand, the proximal positive charge is indeed conjugated to one phosphanyl group, and the coordination scheme is tentatively interpreted by resonance of the phosphane,metal dative bond (+N2C,P:,[Pd]) with a carbene,phosphenium dative bond (N2C:,[+P:,Pd]). Despite this peculiar structural feature, the electronic , donation (vs. , acceptation) towards the palladium centre remains lowered in the cationic ligand. This specific property can be a priori valuable in a catalytic process where oxidative addition is not the limiting step. It is indeed shown that although the neutral complex is more active in Suzuki coupling reactions, the cationic complex is more active in Sonogashira-type coupling reactions involving predissociated halide substrates, namely an acyl chloride. These likely atropo-chiral ligands deserve to be resolved for application in asymmetric catalysis.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] Increased Efficacies of an Individual Catalytic Site in Clustered Multivalent Dendritic CatalystsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2009Govindasamy Jayamurugan Abstract In the studies reported so far on dendrimer-mediated catalysis, the efficacies of the catalytic units were studied and compared primarily across the generations. In order to identify the efficacy of an individual catalytic unit with respect to the number of such units present within a given generation, a series of catalysts were prepared within a generation. Dendrimers incorporated with phosphine-metal complexes were chosen for the study and as many as 11 catalysts within three generations were synthesized. The CC bond-forming reactions, namely, the Heck and the Suzuki coupling reactions, were then selected to study the catalytic efficiencies of the series of partially and fully phosphine-metal complex functionalized dendrimers. The efficacies of the formation of cinnamate and biphenyl, catalyzed by the dendritic catalysts, were compared. The comparative analyses show that an individual catalytic site is far more effective in its catalytic activity when presented in multiple numbers, i.e., in a multivalent dendritic system, than as a single unit within the same generation, i.e., in a monovalent dendritic system. The study identifies the beneficial effects of the multivalent presentation of the catalytic moieties, both within and across the dendrimer generations. [source] Cover Picture: On the Nature of the Active Species in Palladium Catalyzed Mizoroki,Heck and Suzuki,Miyaura Couplings , Homogeneous or Heterogeneous Catalysis, A Critical Review: (Adv. Synth.ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 6 2006Catal. Abstract The cover picture shows several forms of palladium which have been utilized as precatalysts for Heck and Suzuki coupling reactions. Over the years myriad different precat-alysts have been used and the nature of the true catalytic palladium species has been a subject of intense debate. What is the real catalyst in these reactions? For more details see the review by Nam T.,S. Phan, Matthew Van Der Sluys and Christopher W. Jones on pages,609,679. [source] Synthesis and characterization of the soluble fluorescent poly[2-decyloxy-5-(2,-(6,-dodecyloxy)naphthyl)-1,4-phenylenevinylene]JOURNAL OF APPLIED POLYMER SCIENCE, Issue 4 2007Hung-Te Chang Abstract A new soluble fluorescent polymer, poly[2-decyloxy-5-(2,-(6,-dodecyl-oxy)naphthyl)-1,4-phenylenevinylene] (DDN-PPV), with no tolane-bisbenzyl (TBB) structure defects is prepared by the dehydrohalogenation of 1,4-bis(bromomethyl)-2-decyloxy-5-(2,-(6,-dodecyloxy)naphthyl)benzene (as monomer) in this study. The aforementioned monomer is synthesized via such chemical reactions as alkylation, bromination, and Suzuki coupling reactions. The structure and properties of the DDN-PPV are examined by 1H NMR, FTIR, UV/vis, TGA, photoluminescence (PL), and electroluminescence (EL) analyses. The two asymmetric decyloxy and 6,-dodecyloxynaphthyl substituents on the phenylene ring make the DDN-PPV soluble in organic solvents and eliminate the TBB structure defects. With the DDN-PPV acting as a light-emitting polymer, a device is fabricated with a sequential lamination of ITO/PEDOT/DDN-PPV/Ca/Ag. The EL spectrum of the device shows a maximum emission at 538 nm. The turn on voltage of the device is about 16.6 V. Its maximum brightness is 14 cd/m2 at a voltage of 18.2 V. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2734,2741, 2007 [source] White electroluminescence from a single polyfluorene containing bis-DCM unitsJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 15 2007Sang Kyu Lee Abstract A series of fluorene-based copolymers composed of blue- and orange-light-emitting comonomers were synthesized through palladium-catalyzed Suzuki coupling reactions. 9,9-Dihexylfluorene and 2-(2,6-bis-{2-[1-(9,9-dihexyl-9H -fluoren-2-yl)-1,2,3,4-tetrahydroquinolin-6-yl]-vinyl}-pyran-4-ylidene)-malononitrile (DCMF) were used as the blue- and orange-light-emitting chromophores, respectively. The resulting single polymers exhibited simultaneous blue (423/450 nm) and orange (580,600 nm) emissions from these two chromophores. By adjusting the fluorene and DCMF contents, white light emission could be obtained from a single polymer; a device with an ITO/PEDOT:PSS/polymer/Ca/Al configuration was found to exhibit pure white electroluminescence with Commission Internationale de L'Eclairage (CIE) coordinates of (0.33, 0.31), a maximum brightness of 1180 cd/m2, and a current efficiency of 0.60 cd/A. Furthermore, the white light emission of this device was found to be very stable with respect to variation of the driving voltage. The CIE coordinates of the device were (0.32, 0.29), (0.32, 0.29), and (0.33, 0.31) for driving voltages of 7, 8, and 10 V, respectively. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3380,3390, 2007 [source] Palladium-mediated synthesis of novel nimesulide derivativesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 10 2010Shylaprasad Durgadas Abstract Synthesis of a series of compounds structurally related to the anti-inflammatory agent nimesulide has been accomplished via Pd-catalyzed CC bond forming reactions. Thus 4-iodo derivative, prepared from nimesulide, participated in Sonogashira (copper-free), Heck and Suzuki coupling reactions to afford the corresponding alkynyl, alkenyl and aryl substituted products. Some of the compounds synthesized were tested for anti-inflammatory activities in vivo. Copyright © 2010 John Wiley & Sons, Ltd. [source] New route to synthesis of PVP-stabilized palladium(0) nanoclusters and their enhanced catalytic activity in Heck and Suzuki cross-coupling reactionsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 12 2009Feyyaz Durap Abstract Herein we report a new method for the synthesis and characterization of PVP-stabilized palladium(0) nanoclusters and their enhanced catalytic activity in Suzuki coupling and Heck reactions of aryl bromides with phenylboronic acid and styrene, respectively, under mild conditions. The PVP-stabilized palladium(0) nanoclusters with a particle size of 4.5 ± 1.1 nm were prepared using a new method: refluxing a mixture of potassium tetrachloropalladate(II) and PVP in methanol at 80 °C for 1 h followed by reduction with sodium borohydride. Palladium(0) nanoclusters prepared in this way were stable in solution for weeks, could be isolated as solid materials and were characterized by TEM, XPS, UV,vis, and XRD techniques. The PVP-stabilized palladium(0) nanoclusters were active catalysts in Heck and Suzuki coupling reactions of arylbromides with styrene and phenylboronic acid affording stilbenes and biphenyls, respectively, in high yield. Recycling experiments showed that PVP-stabilized palladium(0) nanoclusters could be used five times with essentially no loss in activity in the Heck and Suzuki coupling reactions. Copyright © 2009 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||