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Suzuki Cross-coupling Reaction (suzuki + cross-coupling_reaction)
Selected AbstractsEfficient Diphosphane-Based Catalyst for the Palladium-Catalyzed Suzuki Cross-Coupling Reaction of 3-Pyridylboronic AcidsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 13 2009Xing-Li Fu Abstract A highly active catalyst system derived from PdCl2 and2,2,,6,6,-tetramethoxy-4,4,-bis(diphenylphosphanyl)-3,3,-bipyridine (P-Phos) has been developed for the Suzuki cross-coupling reaction of pyridylboronic acid with a variety of aryl halides in good to excellent yields, even in the presence of hindered and functional groups. In addition, P-Phos also exhibited high activity in the palladium-catalyzed Suzuki reaction of 2,6-dimethoxypyridylboronic acid in excellent yields with a fast rate. The steric and electronic effects of the P-Phos,palladium complex to this cross-coupling reaction were also discussed.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Studies on the Synthesis of Apoptolidin: Progress on the Stereocontrolled Assembly of the Pseudo Aglycone of ApoptolidinEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 1 2006Bin Wu Abstract Progress on a stereocontrolled total synthesis of the pseudo aglycone of apoptolidin (2) starting from (S)-epichlorohydrin is reported. The lower C(12),C(28) fragment (4) was derived by consecutive stereoselective aldol reactions and extended using a Suzuki cross-coupling reaction. Studies on glycoyslation of the C9 hydroxy group are also described. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006) [source] Synthesis of New Thiophene-Substituted 3,3-Diphenyl-3H -naphtho[2,1- b]pyrans by Cross-Coupling Reactions, Precursors of Photomodulated MaterialsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 15 2003Michel Frigoli Abstract 3,3-Diphenyl-3H -naphtho[2,1- b]pyrans linked to one, two, or three thiophene nuclei in different positions of the naphthalene moiety (5, 6, 8, and 9) by a covalent bond have been prepared in good yields. A Suzuki cross-coupling reaction was used with two possible strategies: chromenization before the coupling with oligothiophenes or chromenization after the coupling, the main intermediates being the diphenyl propargylic alcohol, the functionalized naphthol derivatives, and the thiophenic boronates. The overall yields for obtaining such photochromic compounds are generally quite satisfying. For the 7-position, the coupling reaction has been realized using a Grignard reaction between a tetralone derivative and a thiophenic bromo magnesium intermediate. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003) [source] Multifunctional Fluorene-Based Oligomers with Novel Spiro-Annulated Triarylamine: Efficient, Stable Deep-Blue Electroluminescence, Good Hole Injection, and Transporting Materials with Very High TgADVANCED FUNCTIONAL MATERIALS, Issue 24 2009Zuoquan Jiang Abstract A series of fluorene-based oligomers with novel spiro-annulated triarylamine structures, namely DFSTPA, TFSTPA, and TFSDTC, are synthesized by a Suzuki cross-coupling reaction. The spiro-configuration molecular structures lead to very high glass transition temperatures (197,253,°C) and weak intermolecular interactions, and consequently the structures retain good morphological stability and high fluorescence quantum efficiencies(0.69,0.98). This molecular design simultaneously solves the spectral stability problems and hole-injection and transport issues for fluorene-based blue-light-emitting materials. Simple double-layer electroluminescence (EL) devices with a configuration of ITO/TFSTPA (device A) or TFSDTC (device B)/ TPBI/LiF/Al, where TFSTPA and TFSDTC serve as hole-transporting blue-light-emitting materials, show a deep-blue emission with a peak around 432,nm, and CIE coordinates of (0.17, 0.12) for TFSTPA and (0.16, 0.07) for TFSDTC, respectively, which are very close to the National Television System Committee (NTSC) standard for blue (0.15, 0.07). The maximum current efficiency/external quantum efficiencies are 1.63,cd A,1/1.6% for device A and 1.91,cd A,1/2.7% for device B, respectively. In addition, a device with the structure ITO/DFSTPA/Alq3/LiF/Al, where DFSTPA acts as both the hole-injection and -transporting material, is shown to achieve a good performance, with a maximum luminance of 14,047,cd m,2, and a maximum current efficiency of 5.56,cd A,1. These values are significantly higher than those of devices based on commonly usedN,N,-di(1-naphthyl)- N,N,-diphenyl-[1,1,-biphenyl]-4,4,-diamine (NPB) as the hole-transporting layer (11,738,cd m,2 and 3.97,cd A,1) under identical device conditions. [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] Main-Chain Liquid Crystalline Polymers Based on Bis-Etherified 9,9-Dihexyl-2,7-bis(4,-hydroxy-1,1,-biphen-4-yl)fluorenesMACROMOLECULAR CHEMISTRY AND PHYSICS, Issue 13 2007Tanja Sovi Abstract A series of liquid crystalline compounds based on 2,7-bis(biphenyl)fluorenes was synthesised by a Suzuki cross-coupling reaction and subsequent etherification with different bromoalkenes. By simple variations of the chain lengths the temperature range in which the nematic mesophase is present could be tuned. The described approach offers the possibility of covalent incorporation of the mesogens into polymers via olefin metathesis techniques, resulting in enlarged stability of the mesophase. Monomers and polymers could be easily aligned on rubbed polyimide substrates as revealed by polarised absorption spectroscopy. [source] A New Class of Blue-Emitting Materials for LED Applications: Triarylamine N -Functionalised 2,7-Linked Carbazole PolymersMACROMOLECULAR RAPID COMMUNICATIONS, Issue 10 2007Hunan Yi Abstract Attachment of triarylamino-functional groups at the 9-position of 2,7-linked carbazole polymers results in blue-emitting materials with two independent redox processes that were attributed to the triarylamino groups and the polymer backbone, respectively. This new class of blue-emitting conjugated polymers was prepared via a Suzuki cross-coupling reaction and showed low turn-on voltages in electroluminescent devices as a result of their low ionisation potentials. The photophysical, electrochemical and electroluminescent properties of these materials are discussed. [source] Preparation and catalytic properties of bis(imino)pyridine palladium(II) complexes as efficient catalysts for Suzuki cross-coupling reaction in waterAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2009Ping Liu Abstract Air-stable bis(imino)pyridine palladium(II) complexes were synthesized and complex 12 proved to be a highly efficient catalyst for the Suzuki cross-coupling reaction between aryl bromides and arylboronic acids in air using water as solvent. The coupling reaction proceeded smoothly under mild conditions to provide biaryls in excellent yields and Pd black was not observed. The recycling of the catalysts was also investigated, for up to three cycles, and complex 12 still exhibited good activity. Copyright © 2009 John Wiley & Sons, Ltd. [source] Triplet MLCT Photosensitization of the Ring-Closing Reaction of Diarylethenes by Design and Synthesis of a Photochromic Rhenium(I) Complex of a Diarylethene-Containing 1,10-Phenanthroline LigandCHEMISTRY - A EUROPEAN JOURNAL, Issue 22 2006Chi-Chiu Ko Dr. Abstract Synthesis of the diarylethene-containing ligand L1 based on Suzuki cross-coupling reaction between thienyl boronic acid and the dibromophenanthroline ligand is reported. On coordination to the rhenium(I) tricarbonyl complex system, the photochromism of L1 could be photosensitized and consequently extended from intraligand excitation at ,,340 nm in the free ligand to metal-to-ligand charge-transfer (MLCT) excitation at ,,480 nm in the complex. The photochromic reactions were studied by 1H NMR, UV/Vis, and steady-state emission spectroscopy. Photosensitization was further probed by ultrafast transient absorption and time-resolved emission spectroscopy. The results provided direct evidence that the formation of the closed form by the MLCT-sensitized photochromic process was derived from the 3MLCT excited state. This supports the photosensitization mechanism, which involves an intramolecular energy-transfer process from the 3MLCT to the 3IL(L1) state that initiated the ring-closure reaction. The photophysical and electrochemical properties of the complex were also investigated. [source] Synthesis of Dicarboxylate "C-Clamp" 1,2-Diethynylarene Compounds as Potential Transition-Metal Ion HostsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 1 2008Erwin Reisner Abstract We report an efficient convergent synthesis of a new type of C-clamp ligand with a 1,2-diethynylarene scaffold involving a chelate host capable of binding a guest molecule in its endo -dicarboxylate pocket. The chemistry involves a combination of palladium-catalyzed Sonogashira, Heck, and Suzuki cross-coupling reactions. The compounds 2,3-bis[2-(2,-carboxybiphenyl-4-yl)ethynyl]triptycene and 4,5-bis[2-(2,-carboxybiphenyl-4-yl)ethynyl]veratrole and their 2,-carboxy- m -terphenyl-4-yl analogues were designed as dinucleating ligands to assemble carboxylate-bridged transition-metal complexes with a windmill geometry. The X-ray crystal structure of one such C-clamp compound containing co-crystallized water molecules reveals strong hydrogen bonds of the aqua guest to the endo -oriented carboxylic acid entities of the C-clamp host. In addition, two syn -N-donor ligands were prepared as a synthetic scaffold to mimic the geometric arrangement of N-donor atoms in carboxylate-bridged dinuclear proteins. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) [source] A Lutidine-Bridged Bis-Perimidinium Salt: Synthesis and Application as a Precursor in Palladium-Catalyzed Cross-Coupling ReactionsADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 7-8 2009Tao Tu Abstract A novel lutidine-bridged bis-perimidinium dibromide 3 was synthesized in quantitative yield from cheap commercial starting materials. The bisylidene prepared therefrom in situ upon deprotonation is a potent precatalyst in palladium-catalyzed Heck and Suzuki cross-coupling reactions under aerobic conditions, and is efficient even with a ppm scale catalyst loading. Its stronger ,-donor character is held to be responsible for its superior catalytic performance compared with imidazole- and benzimidazole-based analogues bearing the same skeleton precursors. [source] Synthesis and microwave-assisted catalytic activity of novel bis-benzimidazole salts bearing furfuryl and thenyl moieties in Heck and Suzuki cross-coupling reactionsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 5 2010lmaz, Ülkü Y Abstract A mixture of bis-benzimidazole salts (1,7), Pd(OAc)2 and K2CO3 in DMF H2O catalyzes, in high yield, the Suzuki and Heck cross-coupling reactions assisted by microwave irradiation in a short time. In particular, the yields of the Heck and Suzuki reactions with aryl bromides were found to be nearly quantative. The synthesized bis-benzimidazole salts (1,7) were identified by 1H13C NMR, IR spectroscopic methods and micro analysis. 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] Synthesis and characterization of transition metal complexes of thiophene-2-methylamine: X-ray crystal structure of palladium (II) and platinum (II) complexes and use of palladium(II) complexes as pre-catalyst in Heck and Suzuki cross-coupling reactionsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 11 2009Murat Aydemir Abstract The reactions of thiophene-2-(N -diphenylphosphino)methylamine, Ph2PNHCH2 -C4H3S, 1 and thiophene-2-[N,N -bis(diphenylphosphino)methylamine], (Ph2P)2NCH2 -C4H3S, 2, with MCl2(cod) (M = Pd, Pt; cod = 1,5-cyclooctadiene) or [Cu(CH3CN)4]PF6 yields the new complexes [M(Ph2PNHCH2 -C4H3S)2Cl2], M = Pd 1a, Pt 1b, [Cu(Ph2PNHCH2 -C4H3S)4]PF6, 1c, and [M(Ph2P)2NCH2 -C4H3S)Cl2], M = Pd 2a, Pt 2b, {Cu[(Ph2P)2NCH2 -C4H3S]2}PF6, 2c, respectively. The new compounds were isolated as analytically pure crystalline solids and characterized by 31P-, 13C-, 1H-NMR and IR spectroscopy and elemental analysis. Furthermore, the solid-state molecular structures of representative palladium and platinum complexes of bis(phosphine)amine, 2a and 2b, respectively, were determined using single crystal X-ray diffraction analysis. The palladium complexes were tested as potential catalysts in the Heck and Suzuki cross-coupling reactions. Copyright © 2009 John Wiley & Sons, Ltd. [source] Synthesis and characterizations of N,N,-bis(diphenylphosphino)-2-(aminomethyl)aniline derivatives: application of a palladium(II) complex as pre-catalyst in Heck and Suzuki cross-coupling reactionsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 3 2009Murat Aydemir Abstract The reaction of 2-(aminomethyl)aniline with 2 equivalents of PPh2Cl in the presence of Et3N, proceeds in CH2Cl2 to give N,N,-bis(diphenylphosphino)-2-(aminomethyl)aniline 1 in good yield. Oxidation of 1 with aqueous H2O2, elemental sulfur or gray selenium gave the corresponding oxide, sulfide and selenide dichalcogenides [Ph2P(E)NHC6H4CH2NHP(E)Ph2] (E: O, 2a; S, 2b; Se, 2c), respectively. The reaction of [Ph2PNHC6H4CH2NHPPh2] with PdCl2(cod), PtCl2(cod) and [Cu(MeCN)4]PF6 gave the corresponding chelate complexes, PdCl21, PtCl21 and [Cu(1)2]PF6. The new compounds were fully characterized by NMR, IR spectroscopy and elemental analysis. The catalytic activity of the Pd(II) complex was tested in the Suzuki coupling and Heck reactions. The Pd(II) complex catalyzes the Suzuki coupling and Heck reaction, affording biphenyls and stilbenes respectively, in good yields. Copyright © 2009 John Wiley & Sons, Ltd. [source] | |||||||||||||