- Intramolecular Electron Transfer from Pentacyanoferrate(II) to Pentaaminecobalt(III) with 3,3'-Dimethyl-4,4'-bipyridine, 4,4'-Bipyridylacetylene, 1,4-Bis(4-pyridyl)butadiyne, 2,7-Diazapyrene, and 3,8-Phenanthroline as Bridging Ligands: Adiabaticity and th
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Rate constants for intramolecular electron transfer from iron to cobalt in (NH3)5CO(III)LFe(II)(CN)5 (L=3,3'-dimethyl-4,4'-bipyridine, 4,4'-bipyridylacetylene, 1,4-bis(4-pyridyl)butadiyne, 2,7-diazapyrene, and 3,8-phenanthroline) have been measured at 25
- Lee, Gyu-Hwan,Ciana, Leopoldo Della,Haim, Albert
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Read Online
- On the Reaction of Lithium Diisopropylamide with ?-Deficient Heteroaromatics. A Single Electron Transfer Mechanism
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Evidence is presented in support of one-electron transfer as the key step in the reaction of lithium diisopropylamide (LDA) with ?-deficient heteroaromatics.
- Newkome, George R.,Hager, David C.
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- Synthetic transformations of sesquiterpene lactones 9.*Synthesis of 13-(pyridinyl)eudesmanolides
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[Figure not available: see fulltext.]The reaction of isoalantolactone, a sesquiterpene α-methylidene-γ-lactone, with bromo(iodo)pyridines under the Heck reaction conditions gave 3-(pyridylmethylidene)-8а-methyldecahydronaphtho[2,3-b]furan-2(3Н)-ones and 3-(pyridylmethyl)-8а-methyloctahydronaphtho[2,3-b]-furan-2(4Н)-ones, products of double bond migration. The yield and product ratio depended on the reaction conditions and the nature of halopyridine. The effectiveness of Pd(OAc)2–caffeine catalytic system was demonstrated in this reaction.
- Patrushev, Sergey S.,Shakirov, Makhmut M.,Shults, Elvira E.
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Read Online
- Exploring the pH dependence of viologen reduction by α-carbon radicals derived from Hcy and Cys
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The colorimetric reaction of homocysteine (HCy) with a series of viologen salts suggests a linear correlation between the mid-point reduction potential of Hcy-derived α-carbon radicals and pH.
- Wang, Dong,Crowe, William E.,Strongin, Robert M.,Sibrian-Vazquez, Martha
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Read Online
- Highly efficient removal of paraquat pesticide from aqueous solutions using a novel nano Kaolin modified with sulfuric acid via host–guest interactions
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Contamination of wastewaters with pesticides has significant risk for environmental water. In spite of the rule of Europ, paraquat is used extensively as an herbicide in the all around the world and it is likely to be released into drinking water. Therefore the elimination of it from water is very important. In this paper a new sulfuric acid modified nano kaolin sorbent was synthesized with a simple and low cost method. Thereafter it was applied for removing of paraquat and the experimental conditions such as concentration of herbicide, dose of sorbent and pH of solution were optimized. The results showed the unmodified Kaolin wasn’t able to remove the paraquat efficiently. But with the proposed modified nano Kaolin removal percent reach to 98% in a short time 60 min. Also the results showed this system obeys from Frendluich adsorption isotherm.
- Mohammadzadeh Kakhki, Roya,Karimian, Azam,Saadati Rad, Masoud
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- Suzuki–Miyaura arylation of 2,3-, 2,4-, 2,5-, and 3,4-dibromothiophenes
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A convenient and general method for Suzuki–Miyaura double cross-coupling of various dibromothiophenes was developed. Using a simple and cheap catalytic system Pd(OAc)2/PPh3 in 95% EtOH, various (hetero)arylboronic acids react with dibromothiophenes providing diarylthiophenes, useful in the synthesis of metal–organic frameworks (MOFs), in moderate to excellent yields. The overall efficiency of the catalytic process and slight excess of boronic acids allowed to suppress formation of side products and significantly simplify the purification of products.
- Babkova, Mariia,Baran, Andrei,Petkus, Jana,Shubin, Kirill
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- ELECTRON DONOR, AND METHOD FOR SYNTHESIZING 4, 4'-BIPYRIDINE USING ELECTRON DONOR
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Provided are an electron donor that is easy to handle and can be used to carry out a coupling reaction economically and efficiently through simple operations under mild conditions in a short period of time, and a method for synthesizing 4,4′-bipyridine using the electron donor. The electron donor includes a mixture of a dispersion product obtained by dispersing sodium in a dispersion solvent and 1,3-dimethyl-2-imidazolidinone, and this electron donor is used in the method for synthesizing 4,4′-bipyridine.
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Paragraph 0078-0081; 0087-0111
(2020/09/09)
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- METHOD FOR COUPLING HALOGENATED PYRIDINE COMPOUND WITH HALOGENATED AROMATIC COMPOUND
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There is a demand for the development of a technique according to which a reaction for coupling a halogenated pyridine compound with a halogenated aromatic compound can be performed in a simple manner through a small number of steps without using expensive agents such as a palladium catalyst. A method for coupling a halogenated pyridine compound with a halogenated aromatic compound includes a step of coupling a halogenated pyridine compound with a halogenated aromatic compound to obtain a pyridine compound by reacting, in a reaction solvent, the halogenated pyridine compound and the halogenated aromatic compound with a solution containing an alkali metal.
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Paragraph 0059; 0060
(2020/10/20)
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- Green-Synthesized Nickel Nanoparticles on Reduced Graphene Oxide as an Active and Selective Catalyst for Suzuki and Glaser-Hay Coupling Reactions
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A mild and benign methodology to syntheses biaryls and 1,3-diynes has been demonstrated using the nickel nanoparticles supported on reduced graphene oxide (RGO-Ni) as a heterogeneous catalyst which is prepared using green reagents. A series of substituted biaryls and 1,3-diynes has been synthesised in good to excellent yields through C-C homocoupling reaction of arylboronic acids and terminal alkynes respectively using 1,4-dioxane as a benign solvent. The present ligand-free catalytic system proceeds smoothly under mild conditions, avoids noble and stoichiometric metal reagents and tolerates sensitive functional groups. Also has a wide substrate scope and feasible with other nitrogen and sulphur containing heteroaryl boronic acids. Hot filtration test unambiguously proves the true heterogeneity of the catalyst and which support for the further reusability of the catalyst for several times without any change in the activity. The easy preparation and simple magnetic separation, stability and reusability reveal that as-prepared RGO-Ni as a versatile catalyst for the synthesis of polyaromatic compounds both in academia and industries. Highlights: Green-synthesized RGO-Ni nanocomposite used as a heterogeneous catalyst for Suzuki type (C-C) and Glaser–Hay (C ≡ C) homocoupling coupling reactions. Ligand-free catalytic system and avoids noble and stoichiometric metal reagents Short reaction time with a minimum catalyst (nickel) loading RGO-Ni nanocomposite is highly stable, reusable, and magnetically retrievable.
- Murugan, Karthik,Nainamalai, Devarajan,Kanagaraj, Pavithara,Nagappan, Saravana Ganesan,Palaniswamy, Suresh
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- Decoration of copper foam with Ni nanorods and copper oxide nanosheets to produce a high-stability electrocatalyst for the reduction of CO2: Characterization of the electrosynthesis of isonicotinic acid
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CuO–Cu2O (CuxO) nanosheets were coated on a copper foam substrate by the electrochemical anodization method in an alkaline solution. Constant current coulometry was performed to electrodeposit Ni nanorods on the surface of a Cu/CuxO electrode. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) proved that the copper oxide nanosheets were anchored on the copper foam substrate and modified by Ni nanorods (Cu/CuxO/Ni). The process took place via a facile and inexpensive electrodeposition method. As the results indicate, owing to the synergistic effect of adjacent CuxO and Ni sites, a Cu/CuxO/Ni electrode has a very good and stable electrocatalytic activity to reduce CO2. As tested in this study, the product of the electrocatalytic reduction of CO2 (i.e. activated CO2, or CO2 ??) can be used for the electrocarboxylation of pyridine in mild conditions. Once an electron is transferred from CO2 ?? to pyridine, a pyridine radical anion is formed. Based on the EC'C′CC mechanism, this radical anion reacts with CO2 ?? and produces isonicotinic acid as the main product. In addition, two pyridine radical anions react together and produce a 4,4′-bipyridine dimer. The high stability of the electrocatalyst during the electrolysis process and the simplicity of the workup make the proposed modified electrode appropriate for the electrosynthesis of some organic compounds.
- Mohammadzadeh, Safoora,Zare, Hamid R.,Khoshro, Hossein
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p. 678 - 685
(2019/11/14)
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- Complexation of 2,6-helic[6]arene and its derivatives with 1,1′-dimethyl-4,4′-bipyridinium salts and protonated 4,4'-bipyridinium salts: An acid-base controllable complexation
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2,6-Helic[6]arene and its derivatives were synthesized, and their complexation with 1,1′-dimethyl-4,4′-bipyridinium and protonated 4,4'-bipyridinium salts were investigated in detail. It was found that the helic[6]arene and its derivatives could all form 1:1 complexes with both 1,1′-dimethyl-4,4'-bipyridinium salts and protonated 4,4'-bipyridinium salts in solution and in the solid state. Especially, the helic[6]arene and its derivatives containing 2-hydroxyethoxy or 2-methoxyethoxy groups exhibited stronger complexation with the guests than the other helic[6]arene derivatives for the additional multiple hydrogen bonding interactions between the hosts and the guests, which were evidenced by 1H NMR titrations, X-ray crystal structures and DFT calculations. Moreover, it was also found that the association constants (Ka) of the complexes could be significantly enhanced with larger counteranions of the guests and in less polar solvents. Furthermore, the switchable complexation between the helic[6]arene and protonated 4,4'-bipyridinium salt could be efficiently controlled by acids and bases.
- Li, Jing,Shi, Qiang,Han, Ying,Chen, Chuan-Feng
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p. 1795 - 1804
(2019/08/07)
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- MOF Decomposition and Introduction of Repairable Defects Using a Photodegradable Strut
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Photoswitchable components can modulate the properties of metal organic frameworks (MOFs); however, photolabile building blocks remain underexplored. A new strut NPDAC (2-nitro-1,4-phenylenediacetic acid) that undergoes photodecarboxylation has been prepared and incorporated into a MOF, using post-synthetic linker exchange (PSLE) from the structural analogue containing PDAC (p-phenylenediacetic acid). Irradiation of NPDAC-MOF leads to MOF decomposition and concomitant formation of amorphous material. In addition to complete linker exchange, MOFs containing a mixture of PDAC and NPDAC can be obtained through partial linker exchange. In NPDAC30-MOF, which contains approximately 30 % NPDAC, the MOF retains crystallinity after irradiation, but the MOF contains defect sites consistent with loss of decarboxylated NPDAC linkers. The defect sites can be repaired by exposure to additional PDAC or NPDAC linkers at a much faster rate than the initial exchange process. The photoremoval and replacement process may lead to a more general approach to customizable MOF structures.
- Yan, Jingjing,MacDonald, John C.,Maag, Alex R.,Coudert, Fran?ois-Xavier,Burdette, Shawn C.
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p. 8393 - 8400
(2019/05/28)
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- Homocoupling of arylboronic acids catalyzed by dinuclear copper(I) complexes under mild conditions
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An efficient protocol for C–C coupling has been developed using three iodo-bridged copper(I) complexes as catalysts. Complexes [CuI(bpy)]2 (1), [CuI(phen)]2·DMF (2), and [CuI(Mephen)]2 (3) were successfully synthesized via solvothermal method (bpy = 2,2′-dipyridyl, phen = 1,10-phenanthroline, and Mephen = 2,9-dimethylphenanthroline). The self-coupling reaction of phenylboronic acid was selected as a model reaction to evaluate the catalytic property of the complexes. Moreover, this method tolerates various substituents on the arylboronic acids such as halogens, carbonyls, and nitro groups. It shows that the iodo-bridged Cu(I) center serves as the active site to activate molecular oxygen during the catalytic process. The result illustrates that these complexes were found to be excellent catalysts for self-coupling of arylboronic acids under mild conditions.
- Long, Bing-Fan,Qin, Gui-Fang,Huang, Qin,Xiong, Ting,Mi, Yan,Hu, Fei-Long,Yin, Xian-Hong
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p. 2639 - 2646
(2019/07/17)
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- METHOD FOR SYNTHESIZING BIPYRIDINE COMPOUND AND METHOD FOR MANUFACTURING PYRIDINE COMPOUND
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A target bipyridine compound is synthesized with high purity and a high yield in a simple and safe manner in a short period of time. A method for synthesizing a di-tert-butyl-2,2′-bipyridine compound is provided, and the method includes a step of reacting, in a reaction solvent, a tert-butylpyridine compound with a dispersion product obtained by dispersing an alkali metal in a dispersion solvent. A method for synthesizing a bipyridine compound having no substituents is also provided, and the method includes a step of reacting, in a reaction solvent, pyridine with a dispersion product obtained by dispersing an alkali metal in a dispersion solvent.
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Paragraph 0060; 0139-0142
(2018/10/21)
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- Preparation method of 4,4'-dipyridyl
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The invention provides a preparation method of 4,4'-dipyridyl. The method comprises the step of mixing a compound shown in a formula (I) with 4-pyridine boronic acid for carrying out a reaction in presence of a metal palladium compound to obtain 4,4'-dipyridyl, wherein X is halogen or trifluoromethylsulfonyl. Compared with the prior art, the preparation method provided by the invention takes the compound shown in the formula (I) and the 4-pyridine boronic acid as raw materials as well as takes the metal palladium compound as a catalyst for carrying out a cross coupling reaction; the method hasthe advantages of high reaction conversion rate, short reaction time, mild reaction conditions, no need of high temperature and high pressure, low requirement on equipment,, no need of non-aqueous treatment on a solvent, and simple aftertreatment, thus being suitable for large-scale production.
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Paragraph 0049; 0050; 0051; 0052; 0053; 0054; 0058-0063
(2018/03/26)
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- A preparation method of paraquat (by machine translation)
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The invention provides a preparation method of paraquat, including: S1) metal palladium compound in the presence, of formula (I) with a compound represented by the 4 - pyridine boronic acid mixed reaction, to obtain 4, 4 '- bipyridyl; S2) will be the 4, 4' - bipyridyl with chlorodifluoromethane into salt, get the paraquat; wherein X is halogen or amides. Compared with the prior art, this invention has the formula (I) with a compound represented by the 4 - pyridine boronic acid as the raw material, to palladium metal compound as a catalyst, to carry out the cross-coupling reaction to obtain 4, 4' - bipyridyl, with the methyl chloride salt to obtain the paraquat, the method the reaction conversion is high, the reaction time is short, mild reaction conditions, without the need of high-temperature high-pressure, low requirements on equipment, and does not need to carry on the anhydrous solvent processing, at the same time the method after treatment is simple, the separation of the obtained product, the production process is simplified, is suitable for mass production. (by machine translation)
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Paragraph 0053-0058; 0062-0067
(2018/06/15)
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- Room-temperature borylation and one-pot two-step borylation/Suzuki-Miyaura cross-coupling reaction of aryl chlorides
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A highly efficient room-temperature borylation strategy of aryl chlorides is described. Utilizing Buchwald's second-generation preformed catalyst, boronate esters were obtained for a wide range of substrates in high yield. The method was also applied to Suzuki-Miyaura cross-coupling reaction in a one-pot two-step sequential manner, providing a facile and convenient access to the direct synthesis of biaryl compounds from aryl chlorides.
- Ji, Hong,Wu, Li-Yang,Cai, Jiang-Hong,Li, Guo-Rong,Gan, Na-Na,Wang, Zhao-Hua
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p. 13643 - 13648
(2018/04/24)
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- Acid/base-controllable fluorescent molecular switches based on cryptands and basic N-heteroaromatics
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Two kinds of fluorescent BMP32C10-based cryptands 1 and 2 have been developed. Cryptand 1 contains a binaphthol group, while cryptand 2 bears a coumarin group in their third arms. Based on this design, novel self-assemblies constructed from cryptand 1 or 2 and basic N-heteroaromatic guests 3-6 were successfully obtained. Moreover, the threading/dethreading processes of the host-guest complexes could be well switched by the alternate addition of acid/base, and accompanied by concurrent changes in fluorescence.
- Cheng, Ming,Zhang, Jing,Ren, Xintong,Guo, Shuwen,Xiao, Tangxin,Hu, Xiao-Yu,Jiang, Juli,Wang, Leyong
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p. 11838 - 11841
(2017/11/03)
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- A highly efficient gas-dominated and water-resistant flame retardant for non-charring polypropylene
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Traditional phosphorus-nitrogen (P-N) flame-retardant systems for polypropylene (PP) always act through joint action of the gaseous phase and condensed phase, and are accompanied with a decrease of the thermal stability and water resistance. In this work, a novel mono-component and gas-dominated flame retardant, named DPPIP, was prepared through an amidation reaction of diphenylphosphinyl chloride and piperazine, and used to flame retard PP. Experimental results confirmed that both the thermal stability and water resistance of PP/DPPIP were improved. The initial thermal decomposition temperature of PP/25 wt% DPPIP at 5 wt% weight loss was 287.5 °C under air atmosphere, which is higher than that of neat PP (266.1 °C). Besides, a water-resistance test verified that PP/25 wt% DPPIP had a weight loss of only about 0.52 wt%. More importantly, the flame retardant ability of PP/25 wt% DPPIP had been greatly improved, passing the V-0 rating (UL-94). Furthermore, after the water-resistance test, the LOI value of PP/25 wt% DPPIP exhibited nearly no difference and still passed the UL-94 V-0 rating. A cone calorimeter (CC) result indicated that DPPIP had a positive effect on inhibiting heat release of PP during combustion. All of these combustion tests displayed that there was no char left. The flame retardant mechanism of DPPIP was investigated with py-GC/MS and TG-FTIR. The results illustrated that the gaseous phase resulting from the thermal decomposition of DPPIP played the leading role in the self-extinguishing behavior of PP/DPPIP, which consisted of a large amount of inflammable gaseous products such as piperazine and its derivatives, and phosphorus-containing structures.
- Shao, Zhu-Bao,Zhang, Ming-Xin,Han, Ye,Yang, Xu-Dong,Jin, Jing,Jian, Rong-Kun
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p. 51919 - 51927
(2017/11/22)
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- Copper-free palladium-catalysed desulfinative homocoupling of sodium arylsulfinates under mild and aerobic conditions
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A Pd(II)-catalysed homocoupling of sodium arylsulfinates has been successfully achieved under mild conditions. This transformation is a new method for the homocoupling reaction of sodium arylsulfinates, thus providing an alternative synthesis of symmetric biaryls. The reported homocoupling reaction is tolerant to many common functional groups, such as ester, halo, cyano and nitro and works well in the presence of electron-donating and electron-withdrawing substituents. Notably, the reported desulfinative homocoupling does not require Cu salts, ligands and bases, making this newly developed transformation attractive.
- Zhang, Wei
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- With the catalytic 4 - triazole oxygen ether pyridobenzodiazepinones boric acid-copper complex and its preparation method
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The invention discloses a preparation method of [Cu(L)2(NO3)2] (1) (L=1-(4-(4-(1H-1,2,4-triazole-1-yl) phenoxyl) phenyl)-1H-1,2,4-triazole), and the [Cu(L)2(NO3)2] (1) (L=1-(4-(4-(1H-1,2,4-triazole-1-yl) phenoxyl) phenyl)-1H-1,2,4-triazole) has a potential application value of catalyzing a coupling reaction of 4-pyridine phenylboronic acid. A normal temperature evaporation method is adopted, namely, the complex is prepared from Cu(NO3)2 and L under a normal temperature stirring volatilization condition. The invention further discloses an application of the [Cu(L)2(NO3)2] (1) (L=1-(4-(4-(1H-1,2,4-triazole-1-yl) phenoxyl) phenyl)-1H-1,2,4-triazole) serving as a coupling reaction catalyst of the 4-pyridine phenylboronic acid.
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Paragraph 0043; 0047; 0048
(2017/09/26)
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- 1,4-dimethyl-2,5-di-1H-1,2,4-ditriazole copper mixed complex single crystal and application
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The invention discloses a 1,4-dimethyl-2,5-di-1H-1,2,4-ditriazole m-methyl isophthalic acid copper mixed complex single crystal and a preparation method and application thereof. The structure of the single crystal is {[Cu(L)(mipt)(H2O)]DMAC.H2O}, wherein L is equal to 1-(2,5-dimethyl-4(1H-1,2,4-triazole-1-yl)phenyl)-1H-1,2,4-triazole; mipt is equal to m-methyl isophthalic acid; DMAC is equal to N,N'-dimethylacetamide. The invention further discloses the preparation method of the single crystal. According to the preparation method, a normal temperature volatilization method is adopted, that is, L, mipt and CuCl2.4H2O are stirred in water and DMAC for half an hour before being filtered, filtrate is volatilized at normal temperature for two weeks, and then the colorless bulk crystal suitable for X-ray single crystal diffraction is obtained, wherein the molar ratio of L to mipt to CuCl2.4H2O is 1:1:1. The invention further discloses the specific application of the 1,4-dimethyl-2,5-di-1H-1,2,4-ditriazole m-methyl isophthalic acid copper complex single crystal to a catalyst for generation of 4,4'-difluorobiphenyl from p-fluorophenylboronic acid.
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Paragraph 0016; 0017; 0018
(2017/01/02)
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- Homocoupling reactions of terminal alkynes and arylboronic compounds catalyzed by in situ formed Al(OH)3-supported palladium nanoparticles
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Palladium nanoparticles supported on newly generated Al(OH)3was found to be a highly efficient catalyst in oxidative homo-couplings of (Het)aryl alkynes, (Het)arylboronic acids and potassium (Het)aryltrifluoroborates, respectively. Moderate to excellent yields of symmetrical 1,3-diynes and biaryls were obtained under mild conditions.
- Li, Xing,Li, Dongjun,Bai, Yana,Zhang, Congxia,Chang, Honghong,Gao, Wenchao,Wei, Wenlong
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supporting information
p. 6996 - 7002
(2016/10/14)
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- Solvent-Induced Single Crystal-Single Crystal Transformation of an Interpenetrated Three-Dimensional Copper Triazole Catalytic Framework
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The 2-fold interpenetrated 3D framework 1 can be solvent-induced to noninterpenetrated framework 1′ in a reversible single crystal-single crystal transformation fashion. In addition, 1′ represents the first catalyst based on triazole to catalyze the aerobic homocoupling of various substituted arylboronic acids.
- Wang, Ying,Meng, Shan-Shan,Lin, Peng-Xiang,Xiao, Yi-Wei,Ma, Qing-Qing,Xie, Qiong,Chen, Yuan-Yuan,Zhao, Xiao-Jun,Chen, Jun
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supporting information
p. 4069 - 4071
(2016/05/24)
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- A Copper-Based Metal-Organic Framework Acts as a Bifunctional Catalyst for the Homocoupling of Arylboronic Acids and Epoxidation of Olefins
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A copper(I)-based metal-organic framework ({[Cu2Br2(pypz)]na.nH2O} (Cu-Br-MOF) [pypz=bis[3,5-dimethyl-4-(4'-pyridyl)pyrazol-1-yl] methane] has been synthesized by using an elongated and flexible bridging ligand. The structure analysis reveals that each pypz ligand acts as a tritopic ligand connected to two Cu2Br2 dimeric units, forming a one-dimensional zig-zag chain, and these chains further connected by a Cu2Br2 unit, give a two-dimensional framework on the bc-plane. In the Cu2Br2 dimeric unit, the copper ions are four coordinated, thereby possessing a tetrahedral geometry; this proves to be an excellent heterogeneous catalyst for the aerobic homocoupling of arylboronic acids under mild reaction conditions. This method requires only 3 mol % of catalyst and it does not require any base or oxidant-compared to other conventional (Cu, Pd, Fe, and Au) catalysts-for the transformation of arylboronic acids in very good yields (98 %). The shape and size selectivity of the catalyst in the homocoupling was investigated. The use of the catalyst was further extended to the epoxidation of olefins. Moreover, the catalyst can be easily separated by simple filtration and reused efficiently up to 5 cycles without major loss of reactivity.
- Parshamoni, Srinivasulu,Telangae, Jyothi,Sanda, Suresh,Konar, Sanjit
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p. 540 - 547
(2016/03/12)
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- With catalytic 4 --boric acid of the anthracycline double-triazole-four fluoboric acid copper complex and method of preparing the same
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The invention discloses a preparation method of {[Cu(tatrz)2(H2O)2] (BF4)2} (1) (tatrz=1-[9-(1H-1, 2, 4-triazole-1-yl)anthracene-10-yl]-1H-1, 2, 4-triazole) and a potential application value of {[Cu(tatrz)2(H2O)2] (BF4)2} (1) (tatrz=1-[9-(1H-1, 2, 4-triazole-1-yl)anthracene-10-yl]-1H-1, 2, 4-triazole) for catalyzing coupled reaction of 4-pyridinylphenylboronic acid. The complex is prepared by using a normal-temperature volatilization method comprising the step of volatilizing by stirring Cu(BF4)2 and tatrz at normal temperature. The invention further discloses application of {[Cu(tatrz)2(H2O)2] (BF4)2} (1) (tatrz=1-[9-(1H-1, 2, 4-triazole-1-yl)anthracene-10-yl]-1H-1, 2, 4-triazole) as a catalyst for coupled reaction of 4-pyridinylphenylboronic acid.
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Paragraph 0042; 0045-0047
(2016/10/08)
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- With catalytic 4 --boric acid triazole-four fluoboric acid copper complex and method of preparing the same
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The invention discloses a preparation method of {[Cu(L)](BF4)2.0.5H2O} (1)(L=4-(3-(4H-1,2,4- triazole-1-yl)-4H-1,2,4-triazole), and the {[Cu(L)](BF4)2.0.5H2O} (1)(L=4-(3-(4H-1,2,4- triazole-1-yl)-4H-1,2,4-triazole) has a potential application value of a coupling reaction catalyst of 4-pyridine phenylboronic acid. A hydrothermal method is adopted, namely, the complex is prepared from Cu(BF4)2 and L under a hydrothermal condition of 100 DEG C. The invention further discloses an application of the {[Cu(L)](BF4)2.0.5H2O} (1)(L=4-(3-(4H-1,2,4- triazole-1-yl)-4H-1,2,4-triazole) serving as the coupling reaction catalyst of the 4-pyridine phenylboronic acid.
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Paragraph 0040; 0043-0045
(2017/03/14)
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- With catalytic 4 --boric acid of the anthracycline double-triazole-perchloricacid copper complex and method of preparing the same
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The invention discloses a preparation method of {[Cu(tatrz)2(H2O)2] (ClO4)2.4CH3OH} (1) (tatrz=1-[9-(1H-1, 2, 4-triazole-1-yl)anthracene-10-yl]-1H-1, 2, 4-triazole) and a potential application value of {[Cu(tatrz)2(H2O)2] (ClO4)2.4CH3OH} (1) (tatrz=1-[9-(1H-1, 2, 4-triazole-1-yl)anthracene-10-yl]-1H-1, 2, 4-triazole) for catalyzing coupled reaction of 4-pyridinylphenylboronic acid. The complex is prepared by using a normal-temperature volatilization method comprising the step of volatilizing by stirring Cu(ClO4)2 and tatrz at normal temperature. The invention further discloses application of {[Cu(tatrz)2(H2O)2] (ClO4)2.4CH3OH} (1) (tatrz=1-[9-(1H-1, 2, 4-triazole-1-yl)anthracene-10-yl]-1H-1, 2, 4-triazole) as a 4-pyridinylphenylboronic acid coupled reaction catalyst.
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Paragraph 0047-0048
(2017/05/12)
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- Dual activity of electrocatalytic activated CO2 toward pyridine for synthesis of isonicotinic acid: An EC′C′C mechanism
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The present study demonstrates the indirect electrocatalytic synthesis of isonicotinic acid using a Ni complex, [NiII(Me4-(NO2Bzo)2[14]tetraeneN4)], in an acetonitrile solution at room temperature. The complex was used as an excellent electrocatalyst for the reduction of carbon dioxide. The results indicate that the electrocatalytic reduction product of CO2 (CO2·-) has a dual role in the electrosynthesis of isonicotinic acid. The dual activity of CO2·- involved indirect electrocatalytic reduction of pyridine as well as its radical reaction with pyridine radical anion to form isonicotinic acid. Finally, EC′C′C mechanism was proposed for the synthesis of isonicotinic acid. In contrast, the reaction of pyridine with CO2 in the absence of the complex follows an EC′C mechanism, and the final product is 4,4′-bipyridine.
- Khoshro, Hossein,Zare, Hamid R.,Jafari, Abbas A.,Gorji, Alireza
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- The titanium tris-anilide cation [Ti(N[tBu]Ar)3]+ stabilized as its perfluoro-tetra-phenylborate salt: Structural characterization and synthesis in connection with redox activity of 4,4′-bipyridine dititanium complexes
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This work explores the reduction of 4,4′-bipyridine using two equivalents of the titanium(iii) complex Ti(N[tBu]Ar)3 resulting in formation of a black, crystalline complex, (4,4′-bipy){Ti(N[tBu]Ar)3}2, for which an X-ray structure determination is reported. The neutral, black, 4,4′-bipyridine-bridged bimetallic was found to be redox active, with mono- and di-anions being accessible electrochemically, and with the mono- and di-cations also being accessible chemically, and isolable, at least when using the weakly coordinating anion [B(C6F5)4]- as the counter-ion. It proved possible to crystallize the salt [(4,4′-bipy){Ti(N[tBu]Ar)3}2][B(C6F5)4]2 for a single-crystal X-ray structure investigation; in this instance it was revealed that the aromaticity of the 4,4′-bipyridine ligand, that had been disrupted upon reduction, had been regained. A rare cationic d0 metal tris-amide complex, shown by X-ray crystallography to contain an intriguing pyramidal TiN3 core geometry, namely {Ti(N[tBu]Ar)3}+, could also be isolated when using [B(C6F5)4] as the essentially non-interacting counter-ion. This highly reactive cation should be considered as a potential intermediate in the plethora of reactions wherein Ti(N[tBu]Ar)3 has been shown to effect the reduction of substrates including halogenated organic molecules, carbonyl compounds, organic nitriles, and metal complexes. This journal is
- Spinney, Heather A.,Clough, Christopher R.,Cummins, Christopher C.
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p. 6784 - 6796
(2015/04/14)
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- Single-step oxidative homocoupling of aryl Grignard reagents via Co(II), Ni(II) and Cu(II) Complexes under air
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A simple catalytic system of direct synthesis for the symmetrical biaryls using catalytic amounts of Co(II), Ni(II) and Cu(II) complexes has been developed. The reaction system involves in situ synthesis of Grignard reagents. The complexes, containing bidentate Schiff base and dmit (2-thioxo-1,3-dithiole- 4,5-dithiolate) ligands, were compatible with diverse functionalities and afford a high yield of biaryls in a single step, proving to be promising catalysts in homocoupling reactions. Atmospheric oxygen is used as an oxidant which renders a green, simple and economical catalytic route. Copyright
- Bhat, Aparna P. I.,Bhat, Badekai Ramachandra
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p. 383 - 388
(2014/06/09)
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- Organic super-electron-donors: Initiators in transition metal-free haloarene-arene coupling
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Recent papers report transition metal-free couplings of haloarenes to arenes to form biaryls, triggered by alkali metal tert-butoxides in the presence of various additives. These reactions proceed through radical intermediates, but understanding the origin of the radicals has been problematic. Electron transfer from a complex formed from potassium tert-butoxide with additives, such as phenanthroline, has been suggested to initiate the radical process. However, our computational results encouraged us to search for alternatives. We report that heterocycle-derived organic electron donors achieve the coupling reactions and these donors can form in situ in the above cases. We show that an electron transfer route can operate either with phenanthrolines as additives or using pyridine as solvent, and we propose new heterocyclic structures for the respective electron donors involved in these cases. In the absence of additives, the coupling reactions are still successful, although more sluggish, and in those cases benzynes are proposed to play crucial roles in the initiation process.
- Zhou, Shengze,Anderson, Greg M.,Mondal, Bhaskar,Doni, Eswararao,Ironmonger, Vicki,Kranz, Michael,Tuttle, Tell,Murphy, John A.
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p. 476 - 482
(2014/01/17)
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- Clay encapsulated Cu(OH)x promoted homocoupling of arylboronic acids: An efficient and eco-friendly protocol
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Cu(OH)x has been encapsulated over montmorillonite-KSF by simple ologomeric deposition strategy. The resulting catalyst has been employed for selective homocoupling of arylboronic acids under ambient conditions without requirement of any ligand or base. This catalyst is easy to recover and shows excellent reusability without losing its activity. Techniques like XRD, SEM, TPR, IR, BET surface area measurement and XPS were used to characterize the catalyst. The present method promises for the simple and clean homocoupling of arylboronic acids.
- Dar, Bashir Ahmad,Singh, Snehil,Pandey, Nalini,Singh,Sharma, Priti,Lazar, Anish,Sharma, Meena,Vishwakarma, Ram A.,Singh, Baldev
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p. 232 - 238
(2014/01/06)
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- Aerobic homocoupling of arylboronic acids catalysed by copper terephthalate metal-organic frameworks
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Copper terephthalate MOF is utilised as an environmentally benign, efficient and reusable heterogeneous catalyst to effect the aerobic homocoupling of arylboronic acids yielding the corresponding symmetrical biphenyls under mild reaction conditions. This method tolerates various substituents present in arylboronic acids such as halogens, cyano and nitro groups. The catalytic performance has been compared with that of other copper based MOFs namely MOF-101, [Cu(pdc)2]NH2Me2, [Cu 2(ndc)2ted]n and [Cu(H2L)] n as well as with other copper salt catalysts. Sheldon test confirmed the heterogeneity of the catalyst, which can be reused under optimized conditions with only a minor loss in its activity. A mechanism for the homocoupling reaction is also proposed. The simplicity of catalyst preparation, its stability, substrate selectivity, easy recovery and regeneration designate possible utilization of this catalytic system in a multitude of catalytic reactions and industrial processes. the Partner Organisations 2014.
- Puthiaraj, Pillaiyar,Suresh, Palaniswamy,Pitchumani, Kasi
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p. 2865 - 2875
(2014/05/06)
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- Palladacycles promote the base-free homocoupling of arylboronic acids in air at room temperature
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Homocoupling of arylboronic acids can be successfully achieved in commercial grade THF using [Pd(Phbz)(X)(PPh3)] palladacycles as catalysts (Phbz = N-phenylbenzaldimine; X = imidate or acetate). Symmetric biaryls were obtained in good yields working under mild conditions in an air atmosphere at room temperature. The reaction occurs without the addition of an exogenous base. The reaction conditions were optimized to provide the homocoupled products in excellent yield. Evidence for the transmetallation step being important for precatalyst activation has been gathered. The influence of electronic properties of the arylboronic acids on the outcome of the homocoupling reaction has been assessed through competition experiments. This journal is
- Kapdi, Anant R.,Dhangar, Gopal,Serrano, Jose Luis,De Haro, Jose A.,Lozano, Pedro,Fairlamb, Ian J. S.
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p. 55305 - 55312
(2015/02/18)
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- Copper-catalyzed Hiyama coupling of (hetero)aryltriethoxysilanes with (hetero)aryl iodides
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A CuI-catalyzed Hiyama coupling was achieved, which proceeds in the absence of an ancillary ligand for aryl-heteroaryl and heteroaryl-heteroaryl couplings. A P,N-ligand is required to obtain the best product yields for aryl-aryl couplings. In addition to facilitating transmetalation, CsF is also found to function as a stabilizer of the [CuAr] species, potentially generated as an intermediate after transmetalation of aryltriethoxysilanes with Cu I-catalysts in the absence of ancillary ligands.
- Gurung, Santosh K.,Thapa, Surendra,Vangala, Adarsh S.,Giri, Ramesh
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supporting information
p. 5378 - 5381
(2013/11/06)
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- One-step synthesis of biaryls under mild conditions
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A one-step synthesis of symmetrical biaryls was developed and uses a nickel(III) complex containing a Schiff base and dithiolate ligands as a catalyst for the homocoupling of in situ generated Grignard reagents. The coupling reaction was performed at room temperature with molecular oxygen as the oxidant, which renders the reaction energy-efficient and environmentally friendly. The catalytic methodology is compatible with diverse functionalities, including chlorido, nitro, nitrile, and heteroatoms, and provides biaryls in appreciable yields. A practical, room-temperature nickel(III) catalytic system has been developed for the synthesis of biaryls in one step from the homocoupling of in situ generated Grignard reagents. The use of molecular oxygen as the oxidant makes the system environmentally friendly. The reaction system is compatible with diverse functionalities and affords biaryls in appreciable yields. Copyright
- Bhat, Aparna P. I.,Inam, Fawad,Bhat, Badekai Ramachandra
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p. 7139 - 7144
(2013/11/06)
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- Nickel catalyzed one pot synthesis of biaryls under air at room temperature
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A practical, room temperature catalytic system has been developed for the synthesis of biaryls in one step from the homocoupling of in situ generated Grignard reagents using a nickel(ii) complex. The use of atmospheric oxygen as the oxidant makes the system environmentally friendly. The reaction system is compatible with diverse functionality to afford biaryls in appreciable yields. The Royal Society of Chemistry 2013.
- Bhat, Aparna P. I.,Inam, Fawad,Bhat, Badekai Ramachandra
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p. 22191 - 22198
(2013/11/06)
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- Bimetallic gold-palladium alloy nanoclusters: An effective catalyst for Ullmann coupling of chloropyridines under ambient conditions
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An efficient method for the Ullmann coupling of chloropyridines catalyzed by poly(N-vinylpyrrolidone) (PVP)-stabilized bimetallic Au-Pd alloy nanoclusters (NCs) under ambient conditions is demonstrated. The reaction does not occur with either gold or palladium single-metal clusters alone, nor with a physical mixture of the two metals. The experimental results indicate that the inclusion of Au as a nearest heteroatom is crucial to initiate the coupling and its composition up to 50% is essential to accelerate the reaction. Unlike the conventional transition metal catalysis, 2-chloropyridine was found to be highly reactive as compared to 2-bromopyridine. From the UV-vis and ICP-AES measurements, a significant amount of leached Pd(ii) was observed in the coupling with 2-bromopyridine as compared with 2-chloropyridine, indicating that the leaching process might be a crucial factor in diminishing the reactivity.
- Dhital, Raghu Nath,Kamonsatikul, Choavarit,Somsook, Ekasith,Sakurai, Hidehiro
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p. 3030 - 3035
(2013/11/06)
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- Silica-supported PEI capped nanopalladium as potential catalyst in Suzuki, Heck and Sonogashira coupling reactions
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We present the use of amine-functionalized silica (NH2-SiO 2) as support for palladium nanoparticles (PdNPs) and the use of heterogeneous catalysts (Pd/NH2-SiO2) for the Suzuki, Heck and Sonogashira coupling reactions. The synthesized Pd catalyst is well characterized by XRD, HRTEM, BET, SEM-EDX, FT-IR, and UV-vis spectral techniques. It exhibits efficient catalytic activity for these coupling reactions without the assistance of ligand and copper salts.
- Veerakumar, Pitchaimani,Velayudham, Murugesan,Lu, Kuang-Lieh,Rajagopal, Seenivasan
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p. 247 - 260
(2013/05/09)
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- Homocoupling of aryl Grignard reagents to form biaryls using ruthenium(III) complex, [RuCl(C3S5)(H2O)(PPh 3)2]
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Ruthenium(III) complex, [RuCl(C3S5)(H 2O)(PPh3)2] is an effective catalyst for the homocoupling of the aryl-Grignard reagents (ArMgX) to form biaryl derivatives. The catalytic methodology involves an in situ generation of the Grignard reagents. The method is simpler, economical and of great synthetic utility. The reaction will be environmental friendly due to the involvement of molecular oxygen as oxidant.
- Aparna,Bhat, Badekai Ramachandra
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experimental part
p. 73 - 78
(2012/06/01)
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- Catalytic homocoupling of aryl, alkenyl, and alkynyl halides with Ni(II)-complexes and zirconocene dichloride
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A new catalytic system (cat. (H)2Phen(Me)2· NiCl2 or (MeO)2Dipyr(H)2·NiCl 2, cat. Zr(cp)2Cl2, 2 equiv Mn, and 2 equiv LiCl) has been developed to facilitate the homocoupling of a wide range of aryl, alkenyl, and alkynyl halides.
- Peng, Jianbiao,Liu, Xiang,Kishi, Yoshito
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experimental part
p. 2172 - 2175
(2011/05/05)
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- Synthesis of amido-N-imidazolium salts and their applications as ligands in suzuki-miyaura reactions: Coupling of hetero- aromatic halides and the synthesis of milrinone and irbesartan
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A new catalytic system based on palladium-amido-N-heterocyclic carbenes for Suzuki-Miyaura coupling reactions of heteroaryl bromides is described. A variety of sterically bulky, amido-N-imidazolium salts were synthesized in high yields from the corresponding anilines. This catalytic system effectively promoted Suzuki-Miyaura couplings of heteroaryl bromides and chlorides with a range of boronic acids to give the corresponding aryl compounds in high yield. The yield was increased with increasing steric bulkiness of the substituted group. Especially, 1-(2,6-diisopropylphenyl)-3-N-(2,4,6-tri-tert- butylphenylacetamido)imidazolium bromide (4bc) exhibited 850,000 TON in the coupling reaction of 2-bromopyridine and phenylboronic acid. In addition, pharmaceutical compounds such as milrinone and irbesartan were synthesized via Suzuki-Miyaura coupling using sterically bulky, amido-N-imidazolium salt (4bc) as a ligand. Copyright
- Kumar, Manian Rajesh,Park, Kyungho,Lee, Sunwoo
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supporting information; experimental part
p. 3255 - 3266
(2011/02/23)
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- Efficient homo-coupling reactions of heterocyclic aromatic bromides catalyzed by Pd(OAc)2 using indium
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Homo-coupling reactions of heterocyclic aromatic bromides smoothly proceeded with cat-Pd(OAc)2, indium, and LiCl in DMF to afford exclusively symmetric biaryls possessing heterocyclic aromatic ring in good to excellent yields.
- Lee, Kooyeon,Lee, Phil Ho
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p. 4302 - 4305
(2008/09/21)
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- Heterogenous catalytic method for the synthesis of biquinolines and bipyridines
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A method has been developed for the synthesis of 2,2′- and 3,3′-biquinolines and of 4,4′-bipyridine based on the coupling of 2- and 3-bromoquinoline or 4-bromopyridine using a Pd/C-hydrazine-KOH catalytic system.
- Aksenov,Goncharov
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experimental part
p. 1491 - 1492
(2009/06/17)
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- Method for making nitrogen aromatic oligomers and polymers
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Methods for synthesizing dimeric or higher polymeric reaction products of nitrogen aromatics comprise contacting a composition comprising the nitrogen aromatic with a catalyst composition. The catalyst is in particulate form and comprises a first metal substrate having a second reduced metal coated on the substrate.
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Page/Page column 5
(2008/06/13)
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- Cocondensation reactions of heterocyclic aromatic compounds with lithium, calcium and magnesium atoms at 77 K
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Calcium and magnesium atoms were cocondensed with aromatic heterocycles containing five- and six-membered rings in the presence of THF at 77 K. In the case of calcium the cocondensation with five-membered heterocyclic compounds resulted in C-H bond activations and led to the corresponding aryl calcium compounds, while magnesium did not show comparable reactions. When six-membered heterocyclic compounds, e.g., pyridine and 4-methylpyridine (4-picoline) were cocondensed with calcium, magnesium and lithium atoms, all reactions led to the formation of non-metallated aromatic products and the formation of metal hydride. DFT calculations at the B3LYP/6-31G** level of theory were carried out in order to interpret the pathways of the cocondensation reactions using calcium atoms and identify the possible intermediates involved. In all reactions π- and σ-complexes between calcium atoms and the heterocyclic aromatic reactant were found as stable intermediates on the energy hypersurface.
- Mendoza, Oscar,Tacke, Matthias
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p. 1110 - 1116
(2007/10/03)
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- Organometallic π-tweezers incorporating pyrazine- and pyridine-based bridging units
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The synthesis of heterobimetallic (TiCu, TiAg) and tetranuclear heterobimetallic (Ti2Ag2) transition metal complexes based on the organometallic π-tweezer building blocks [Ti](CCSiMe 3)2 is described. In [{[Ti](μ-σ,π-CCSiMe 3)2}M-LL]+ and [{[Ti](μ-σ,π- CCSiMe3)2}MLLM{(Me3SiCC-μ-σ,π) 2[Ti]}]2+ (M = Cu, Ag; LL = pyrazine- or pyridine-based bridging units) the metal containing parts are spanned by π-conjugated organic bridges LL. Depending on the nature of LL coordination polymers are also accessible. Pyrazine- and pyridine-based π-conjugated σ-donor molecules, such as 4,4′-bipyridine, 1,2-di(4-pyridyl)ethylene, 3,5-dipyridyl-1,2,4-triazole, N,N′-bis(4-pyridylmethylidene)benzene-1,4- diamine, 2,5-di(pyridylmethylidene)cyclopentanone, 2,6-di(4-pyridylmethylidene) cyclohexanone (LL, 2a-2g) can successfully be used to span heterobimetallic π-tweezer units of the type [{[Ti](μ-σ,π-CCSiMe3) 2}M]+ ([Ti] = (η5-C5H 4SiMe3)2Ti; M = Cu, Ag). The thus accessible di-cationic species [{[Ti](μ-σ,π-CCSiMe3) 2}MLLM{(Me3SiCC-μ-σ,π)2[Ti]}] 2+ (4), which are formed via the formation of [{[Ti](μ-σ, π-CCSiMe3)2}MLL]+ (3) complexes, can be isolated in yields between 66% and 99%. However, when C5H 4NCHCHC6H4CHCHNC5H4 (5a) and C5H4NCHNC6H4CHCHNC 5H4 (5b), respectively, are reacted with {[Ti](μ-σ,π-CCSiMe3)2}AgBF4(1c) in a 1:1 molar ratio, then the silver(I) ion is released from the organometallic π-tweezer 1c and coordination polymers [AgBF4 ? 5a] n (6a) and [AgBF4 ? 5b]n (6b) along with [Ti](CCSiMe3)2 (7) are formed in quantitative yield.
- Al-Anber,Stein, Th.,Vatsadze,Lang
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- Aluminium alkyl and aryloxide complexes of pyrazine and bipyridines: Synthesis and structure
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The reaction of AlMe3 and [(tBu)2Al(μ- OPh)]2 with pyrazine (pyz), 4,4′-bipyridine (4-4′-bipy), 1,2-bis(4-pyridyl)ethane (bpetha) and 1,2-bis(4-pyridyl)ethylene (bpethe) yields (Me3Al)2(μ-pyz) (1), (Me3Al) 2(μ-4,4′-bipy) (2), (Me3Al)2(μ- bpetha) (3), (Me3Al)2(μ-bipethe) (4), Al( tBu)2(OPh)(pyz) (5), [(tBu)2Al(OPh)] 2(μ-4,4-bipy) (6a), [(tBu)2Al(OPh)] 2(μ-bpetha) (7a), [(tBu)2Al(OPh)] 2(μ-bipethe) (8a). Compounds 1-4, 6a and 7a have been confirmed by X-ray crystallography. In solution compounds 1-4 undergo a rapid ligand-dissociation equilibrium resulting in a time-average spectrum in the 1H NMR. In contrast, the solution equilibria for compounds 5-8a are sufficiently slow such that the mono-aluminium compounds may be observed by 1H NMR spectroscopy: Al(tBu)2(OPh)(4,4-bipy) (6b), Al(tBu)2(OPh)(bpetha) (7b) and Al( tBu)2(OPh)(bpethe) (8b). The inability to isolate [( tBu)2Al(OPh)]2(μ-pyz) and the relative stability of each complex is discussed with respect to the steric interactions across the bridging ligand (L) and the electronic effect on one Lewis acid-base interaction by the second Lewis acid-base interaction on the same ligand.
- Ogrin, Doug,Van Poppel, Laura H.,Bott, Simon G.,Barron, Andrew R.
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p. 3689 - 3694
(2007/10/03)
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- Palladium-catalyzed tetrakis(dimethylamino)ethylene-promoted reductive coupling of aryl halides
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Tetrakis(dimethylamino)ethylene (TDAE)/cat. PdCl2(PhCN)2-promoted reductive coupling of aryl bromides having either electron-donating or electron-withdrawing groups on their para- and/or meta-position proceeded smoothly to afford the corresponding biaryls in good to excellent yields. Notably, TDAE is such a mild reductant that easily reducible groups, such as carbonyl and nitro groups, are tolerate. A similar reductive coupling of ortho-substituted aryl bromides did not occur at all. The proper choice of palladium catalysts is essential for the reductive coupling; thus, PdCl2-(PhCN)2, PdCl2(MeCN)2, Pd(hfacac)2, Pd2(dba)3, PdCl2, and Pd(OAc)2 were used successively for this reaction, but phosphine-ligated palladium catalysts such as Pd(PPh3)4, PdCl2(PPh3)2, and Pd-(dppp) did not promote the reaction. The reductive coupling did not occur with nickel catalysts such as NiBr2, NiCl2(bpy), and Ni(acac)2. The TDAE/cat. palladium-promoted reductive coupling of aryl halides having electron-withdrawing groups took place more efficiently than that of aryl halides substituted with electron-donating groups. A plausible mechanism of TDAE/cat. palladium-promoted reaction is discussed.
- Kuroboshi, Manabu,Waki, Yoko,Tanaka, Hideo
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p. 3938 - 3942
(2007/10/03)
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- Inhibitors of cell proliferation, angiogenesis, fertility, and muscle contraction
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The invention concerns inhibitors of cell proliferation, angiogenesis, fertility, and muscle contraction, characterized by formula I wherein, X, Y and Z independently represent C or N; ------ is an optional double bond; n is 0 or 1; R1, R2, and R4 independently represent hydrogen, a chemical bond, C1-10 alkyl; C2-10 alkenyl; C2-10 alkinyl; aryl; aryl-C1-10 alkyl; C3-10 heterocyclyl; C5-10 heteroaryl; halo, CF3; NO2; NHC(O)R*, OR, said alkyl, alkenyl, alkinyl, aryl, arylalkyl, heterocyclyl, or heteroaryl being optionally substituted; R3, R5, and R6 independently represent hydrogen, C1-10alkyl; C2-10 alkenyl; C2-10 alkinyl; aryl; aryl-C1-10alkyl; C3-10 heterocyclyl; C5-10 heteroaryl; halo, CF3; NO2; NHC(O)R*, OR, said alkyl, alkenyl, alkinyl, aryl, heterocyclyl, or heteroaryl being optionally substituted; or R5 and R6 together form a 5- or 6-member aryl, heterocyclyl or heteroaryl group; R is hydrogen or C1-6 alkyl; R* is hydrogen, or C1-6 alkyl, or OH, wherein the optional substituents are preferably selected from the group of one to three OH, C1-6 alkyl, halo, NO2, C1-6 alkoxy, and CF3, or a pharmaceutically acceptable salt thereof.
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- Tetrakis(dimethylamino)ethylene (TDAE)-Pd promoted reductive homo-coupling of aryl halides
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A combination of tetrakis(dimethylamino)ethylene (TDAE) and palladium catalysts promoted reductive homo-coupling of aryl halides efficiently to afford the corresponding biaryls in good to quantitative yields. TDAE acted as a very mild reductant, and easily reducible functional groups, such as a nitro formyl, ester, or nitrile group, remained unchanged.
- Kuroboshi, Manabu,Waki, Yoko,Tanaka, Hideo
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p. 637 - 639
(2007/10/03)
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