- Supported gold catalyzes the homocoupling of phenylboronic acid with high conversion and selectivity
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(Chemical Equation Presented) Gold on nanocrystalline cerium oxide is a highly active and selective catalyst for the homocoupling of phenylboronic acid derivatives in the presence of K2CO3 as a base (see picture). Au3+ species are thought to be the active sites for the reaction, and water is required to activate the boronic acid through the participation of surface hydroxy groups.
- Carrettin, Silvio,Guzman, Javier,Corma, Avelino
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Read Online
- Synthesis of Rolivsans containing unsaturated biphenyl units by acid-catalyzed transformations of 4,4′-di(1-hydroxyethyl)biphenyl
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The mechanism and kinetics of formation, and also the structure, composition, and properties of thermosetting resins of a new class, Rolivsans with biphenyl units, were studied.
- Zaitsev,Khramova,Shvabskaya
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Read Online
- "benchtop" Biaryl Coupling Using Pd/Cu Cocatalysis: Application to the Synthesis of Conjugated Polymers
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Typically, Suzuki couplings used in polymerizations are performed at raised temperatures in inert atmospheres. As a result, the synthesis of aromatic materials that utilize this chemistry often demands expensive and specialized equipment on an industrial scale. Herein, we describe a bimetallic methodology that exploits the distinct reactivities of palladium and copper to perform high yielding aryl-aryl dimerizations and polymerizations that can be performed on a benchtop under ambient conditions. These couplings are facile and can be performed by simple mixing in the open vessel. To demonstrate the utility of this method in the context of polymer synthesis: polyfluorene, polycarbazole, polysilafluorene, and poly(6,12-dihydro-dithienoindacenodithiophene) were created at ambient temperature and open to air.
- Minus, Matthew B.,Moor, Sarah R.,Pary, Fathima F.,Nirmani,Chwatko, Malgorzata,Okeke, Brandon,Singleton, Josh E.,Nelson, Toby L.,Lynd, Nathaniel A.,Anslyn, Eric V.
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supporting information
p. 2873 - 2877
(2021/05/05)
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- A porous Br?nsted superacid as an efficient and durable solid catalyst
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The development of catalysts able to assist industrial chemical transformations is a topic of high importance. In view of the versatile catalytic capabilities of acid catalysts, extensive research efforts are being made to develop porous superacid materials with a high density of accessible active sites to replace molecular acid catalysts. Herein, we report the rational development of a porous Br?nsted superacid by combining important elements that target high strength acidity into one material, as demonstrated by grafting the sulfonic acid group onto a highly fluorinated porous framework, where the acid strength and stability are greatly enhanced by an electron-withdrawing environment provided by the polymer backbone, reminiscent of that seen in Nafion resin. In addition, the densely arranged acid groups that are confined in the three-dimensional nanospace facilitate the transfer of hydrons, thereby further increasing the acidity. By virtue of the pore structure and strong acidity, this system exhibits excellent performance for a wide range of reactions, far outperforming commercial acid resins under repeated batch and flow reaction conditions. Our findings demonstrate how this synthetic approach may instruct the future design of heterogeneous acid catalysts with advantageous reaction capabilities and stability.
- Sun, Qi,Hu, Kewei,Leng, Kunyue,Yi, Xianfeng,Aguila, Briana,Sun, Yinyong,Zheng, Anmin,Meng, Xiangju,Ma, Shengqian,Xiao, Feng-Shou
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supporting information
p. 18712 - 18719
(2018/10/15)
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- Efficient Homocoupling of Aryl- and Alkenylboronic Acids in the Presence of Low Loadings of [{Pd(μ-OH)Cl(IPr)} 2 ]
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NHC-palladium(II) complex [{Pd(μ-OH)Cl(IPr)} 2 ] (IPr = bis(2,6-diisopropylphenyl)imidazolin-2-ylidene) catalyzes the oxidative coupling of a broad spectrum of aryl- and alkenylboronic acids at loadings down to 5 ppm. At the concentration of 0.05 mol% the catalyst permits an efficient reaction under base-free conditions.
- Ostrowska, Sylwia,Rogalski, Szymon,Lorkowski, Jan,Walkowiak, Jedrzej,Pietraszuk, Cezary
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supporting information
p. 1735 - 1740
(2018/07/21)
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- A new class of stereoregular vinylene-arylene copolymers with double-decker silsesquioxane in the main chain
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A synthesis of a new macromolecular class of vinylene-arylene copolymers with double-decker silsesquioxane in the main chain is presented. Two transition-metal-catalyzed processes, which is silylative-coupling copolycondensation (SCC) and ADMET copolymerization of divinyl-substituted double-decker silsesquioxanes (DDSQ-2SiVi) with selected diolefins, are reported to be highly efficient tools for the formation of stereoregular copolymers containing DDSQ-silylene-vinylene-arylene units. The copolymeric products are studied in terms of their structural, thermal, and mechanical properties.
- Zak, Patrycja,Dudziec, Beata,Dutkiewicz, Micha?,Ludwiczak, Monika,Marciniec, Bogdan,Nowicki, Marek
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p. 1044 - 1055
(2016/03/12)
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- Ligand-, base-, co-catalyst-free copper fluorapatite (CuFAP) as a versatile, ecofriendly, heterogeneous and reusable catalyst for an efficient homocoupling of arylboronic acid at ambient reaction conditions
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This paper describes the first report in which copper species containing copper fluorapatite (CuFAP) acts as a versatile, eco-friendly, recyclable, heterogeneous catalyst for an efficient synthesis of symmetric biaryls from the homo-coupling of arylboronic acids in methanol solvent at ambient reaction conditions. The developed protocol is ligand-, base-, and co-catalyst-free, sustainable, mild, inexpensive, and compatible with a wide range of aromatic/heterocyclic boronic acids and provides the corresponding products in excellent yields without purification. The catalyst was easily recovered from the reaction mixture and reused several times without loss of activity.
- Mulla, Shafeek A. R.,Chavan, Santosh S.,Pathan, Mohsinkhan Y.,Inamdar, Suleman M.,Shaikh, Taufeekaslam M. Y.
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p. 24675 - 24680
(2015/03/30)
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- Synthesis of 4-vinylbiphenyl derivatives by Pd(II)-1,2-diaminocyclohexane complex catalyzed Suzuki-Miyaura reaction
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A series of 4-vinylbiphenyl derivatives were synthesized by Pd(II)-1,2-diaminocyclohexane complex catalyzed Suzuki-Miyaura reactions in the presence of K3PO4?3H2O as base in toluene at 80 ° C and the corresponding products achieved 39-95% yields. According to this efficient C-C bond-forming method, the obtained yields of 4-vinylbiphenyl liquid crystal compounds were up to 89%.
- Liu,Ma,Liu,Xie,Dai
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p. 8022 - 8024
(2015/02/02)
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- A highly stereoselective synthesis of new styryl-π-conjugate organosilicon compounds
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This work describes very precise and controlled catalytic transformations as useful tools for the synthesis of new trans-π-conjugated molecular and macromolecular organosilicon compounds. Several distyryl-arenes were obtained efficiently via silylative coupling in high yields and with excellent selectivity for new E,E-bis(silyl)arenes.
- Majchrzak, Mariusz,Hybsz, Milena,Kostera, Sylwia,Kubicki, Maciej,Marciniec, Bogdan
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supporting information
p. 3055 - 3058
(2014/05/20)
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- Synthesis of new styrylarenes via Suzuki-Miyaura coupling catalysed by highly active, well-defined palladium catalysts
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An efficient synthetic route for well-defined palladium(0) complexes [Pd(η2-dba)(PPh3)2] (2), [Pd(η2-dba)(PCy3)2] (3) and their crystallographic structures is reported. This is the first crystallographic characterization of palladium complexes coordinated with one dibenzylideneacetone and two phosphines. A highly effective, fully controlled method for selective synthesis of mono- (5-9) and distyrylarenes (10-15) via Suzuki-Miyaura coupling is described. ? The Royal Society of Chemistry 2013.
- Kostera, Sylwia,Kownacki, Ireneusz,Kubicki, Maciej,Majchrzak, Mariusz
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supporting information
p. 15535 - 15539
(2015/11/25)
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- A rapid and efficient catalysis system for the synthesis of 4-vinylbiphenyl derivatives
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A series of 4-vinylbiphenyl derivatives were synthesized by Pd(OAc) 2/PCy3-catalyzed Suzuki-Miyaura reaction in the presence of K3PO4.3H2O as base in toluene at 80°C for only 10-30 min, and the corresponding products achieved 65-98% yields. According to this efficient C - C bond-forming method, the obtained yields of 4-vinylbiphenyl liquid crystal compounds were up to 92-96%. Copyright
- Ma, Xiaowei,Liu, Yan,Liu, Ping,Xie, Jianwei,Dai, Bin,Liu, Zhiyong
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p. 707 - 710
(2013/12/04)
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- Fe3O4 nanoparticle-supported Cu(ii)-β- cyclodextrin complex as a magnetically recoverable and reusable catalyst for the synthesis of symmetrical biaryls and 1,2,3-triazoles from aryl boronic acids
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We report here on the preparation of an efficient, easily recoverable and reusable Fe3O4 magnetic nanoparticle-supported Cu(ii)-β-cyclodextrin complex catalyst for the synthesis of symmetrical biaryls and 1,2,3-triazoles from arylboronic acids. The presented Fe 3O4 magnetic nanoparticle-supported Cu(ii)-β- cyclodextrin complex catalyst was characterized by TEM, XRD, VSM, TGA, and FT-IR spectrometer. By using the catalyst, we have developed an efficient protocol for the homocoupling of aryl boronic acids for the synthesis of biaryls. The catalyst is also active in the synthesis of 1,2,3-triazoles via a one-pot reaction of an arylboronic acid with sodium azide in water followed by a click cyclization reaction with an alkyne at room temperature in air without any additives. The reusability of the prepared nanocatalyst was successfully examined four times with only a very slight loss of catalytic activity.
- Kaboudin, Babak,Mostafalu, Ramin,Yokomatsu, Tsutomu
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p. 2266 - 2274
(2013/09/24)
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- Divinyl aromatic compounds and Di(methacrylates) prepared by acid-catalyzed transformations of bis[4-(1-hydroxyethyl)phenyl]alkanes
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The mechanism of formation of divinyl aromatic monomers including p,p′-divinyldiphenylmethane and 1,2-p,p′-divinyldiphenylethane and of their dimerization via terminal vinyl groups was studied. The factors affecting the structure, composition, and propert
- Zaitsev,Shvabskaya
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experimental part
p. 1783 - 1794
(2012/02/15)
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- Synthesis of 4-substituted styrene compounds via palladium-catalyzed suzuki coupling reaction using free phosphine ligand in air
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The air-stable and easy to prepare nonsymmetric Schiff base ligands have been synthesized and proven to be efficient ligands for Suzuki cross-coupling reaction between aryl bromides and arylboronic acids using PdCl 2(CH3CN)2 as palladium source under aerobic conditions. The coupling reaction proceeded smoothly using N-[(3,4- dimethoxyphenyl)methylene]-1,2-benzenediamine (L3) as ligand under mild conditions to provide 4-substituted styrene compounds in good yields.
- Liu, Yan,Wang, Jinqu
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experimental part
p. 196 - 205
(2010/03/30)
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- Synthesis of biaryl-styrene monomers by microwave-assisted Suzuki coupling
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Biaryl-styrenic monomers are prepared via Suzuki coupling as functional monomers in the synthesis of molecularly imprinted polymers. Traditional thermal Suzuki approaches are hampered by competition between Suzuki, Heck and homo-coupling reactions. Microw
- Zayas, Hazit A.,Bowyer, Michael C.,Gordon, Christopher P.,Holdsworth, Clovia I.,McCluskey, Adam
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body text
p. 5894 - 5895
(2010/01/18)
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- Homocoupling of arylboronic acids catalyzed by 1,10-phenanthroline-ligated copper complexes in air
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The efficient homocoupling of arylboronic acids was achieved by using the catalytic combination of inexpensive copper salts and 1,10-phenanthroline as aligand. The homocoupling reaction proceeds at ambient temperature in air without any additives such as base or oxidant. This method tolerates various substituents on the arylboronic acids such as halogens, carbonyls, and a nitro group. As a result, 25 symmetrical biaryls were obtained from readily available arylboronic acids in 19-92% isolated yields. A binuclear (μ- hydroxido)copper complex is assumed as the catalytically active species, which undergoes efficient transmetalation with arylboronic acids to produce dinuclear arylcopper complexes. The binuclear structure is assumed to be essential for the bimetallic reductive elimination of biaryls as well as the oxidative restoration of the catalyst. Wiley-VCH Verlag GmbH & Co, KGaA.
- Kirai, Naohiro,Yamamoto, Yoshihiko
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experimental part
p. 1864 - 1867
(2009/08/17)
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- Direct vinylation and difluorovinylation of arylboronic acids using vinyl- and 2,2-difluorovinyl tosylates via the Suzuki-Miyaura cross coupling
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(Chemical Equation Presented) General reaction conditions were developed for the Pd(0)-catalyzed Suzuki-Miyaura coupling reaction of aryl boronic acids with a simple electrophilic vinylation reagent, vinyl tosylate, providing access to styrene derivatives in good yields. The easily accessible vinyl tosylate represents a stable and less toxic alternative to the vinyl halides and the triflate/nonaflate derivatives. Furthermore, this methodology was expanded to provide a facile and straightforward approach for the introduction of a gem-difluorovinyl substituent onto an aromatic ring using the similar and also readily available 2,2-difluorovinyl tosylate as the electrophilic complement.
- Gogsig, Thomas M.,Sobjerg, Lina S.,Lindhardt, Anders T.,Jensen, Kim L.,Skrydstrup, Troels
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p. 3404 - 3410
(2008/09/21)
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- Rhodium-catalyzed oxidative homocoupling of boronic acids
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Oxidative homocoupling of aryl- and alkenylboronic acids was achieved with Wilkinson's catalyst. Commercially available 2,2,6,6-tetramethylpiperidine-N- oxyl radical (TEMPO) was used as a stoichiometric oxidant.
- Vogler, Thomas,Studer, Armido
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supporting information; experimental part
p. 1963 - 1967
(2009/08/14)
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- Homocoupling of arylboronic acids with a catalyst system consisting of a palladium(II) N-heterocyclic carbene complex and p-benzoquinone
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In the presence of 1-3 mol% SIPr-ligated Pd(OAc)2 and 0.6 equivalent of p-benzoquinone, various arylboronic acids underwent homocoupling in MeOH at ambient temperature to produce symmetrical biaryls in 38-96% yields. Georg Thieme Verlag Stuttgart.
- Yamamoto, Yoshihiko
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p. 1913 - 1916
(2008/03/13)
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- NiCl2/CrCl2/Mn-mediated homocoupling of aryl halides accomplished in the presence of bipyridyl-type ligand
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Aryl halides are readily homocoupled in a catalytic amount of NiCl2/CrCl2 and bipyridyl-type ligand 1 in the presence of a reducing metal Mn at room temperature subsequently yielding the corresponding biaryls.
- Chen
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p. 1491 - 1492
(2007/10/03)
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- Intermediates
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The present invention provides compounds having the formula: STR1 in which R is hydrogen or C1 -C4 alkyl, preferably hydrogen and Y is hydrogen, C1 -C4 alkyl, C1 -C4 alkoxy, CF3, halogen (F, Cl, Br or I) or SO3 M in which M is H, Na, K, Ca, Mg, ammonium, mono-, di-, tri- or tetra-C1 -C4 alkylammonium, mono-, di- or tri-hydroxyalkylammonium or ammonium that is di- or tri-substituted with a mixture of C1 -C4 alkyl and C1 -C4 hydroxyalkyl groups; a process for their production; and their use as intermediates in the production of asymmetric or symmetric fluorescent whitening agents.
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- Process for the preparation of aromatic vinyl compounds
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A process is described for preparing aromatic vinyl compounds of general formula (I) Ar CH=CH2]nwhich is characterised in that an aromatic acetylene compound of general formula (II) Ar C≡CH]nis selectively hydrogenated at the triple bond on a noble metal catalyst. This process permits ease of access to functional aromatic vinyl compounds. It makes it possible to prepare technically pure products without expensive process measures.
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- Preperations and Reactions of Symmetrical Dimethylenebiphenyl Dianions; Conformations of -o-Cyclophanes. A Simple NMR method for Determining Twist Angles in Biphenyls
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With n-butyllithium / potassium tert-butoxide, a proton is removed from each methyl group of the symmetrical dimethylbiphenyls to give dianions in good yield.The reactions of these dianions with alkyl halides, dialkyl sulfates, trimethylchlorosilane, trimethylchlorogermane, α,ω-dihalides, and oxidizing agents were found to provide the best routes to many symmetrically substituted biphenyls, including - and cyclophanes.NMR and molecular mechanical studies of some of these cyclophanes gave information on their preferred conformations.An NMR method for determining the angle of twist in biphenyls from the chemical shifts of the ortho hydrogens is developed.
- Bates, Robert B.,Camou, Fernando A.,Kane, Vinayak V.,Mishra, Prasana K.,Suvannachut, Kessara,White, James J.
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p. 311 - 317
(2007/10/02)
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- Process for the preparation of styrene derivatives and/or stilbene derivatives
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Compounds of the formulae in which Z represents unsubstituted or substituted phenyl or naphthyl, Z1 represents hydrogen or has the same meaning as Z and Z2 represents unsubstituted or substituted phenylene, naphthylene or p-biphenylene or an unsubstituted or substituted stilbene radical, can be obtained in a simple and economical manner in accordance with a novel process by reacting ethylene, under a pressure of 0.1 to 20 bar, in the presence of a base and with the addition of specific palladium catalysts, such as palladium acetate, with appropriate acid halides. The compounds of the formulae Ia and Ib are valuable intermediates, in particular for the preparation of fluorescent brighteners or scintillators.
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