- Halogenation of Aromatic Compounds by N-chloro-, N-bromo-, and N-iodosuccinimide
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An efficient and mild method for the halogenation of aromatic compounds using N-chloro-, N-bromo-, and N-iodosuccinimide in the presence of NH 4NO3 or FeCl3 in acetonitrile was developed.
- Tanemura, Kiyoshi,Suzuki, Tsuneo,Nishida, Yoko,Satsumabayashi, Koko,Horaguchi, Takaaki
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- Nucleophilic reactions of 5-(aryl)thianthrenium bromides with sodium aryl oxides
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Reactions between 5-(aryl)thianthrenium bromides (1a-e) with aryl (Ar) groups phenyl (a), p-tolyl (b), p-anisyl (c), p-chlorophenyl (d) and p-bromophenyl (e) and sodium aryl oxides (7a-c, Ar′ONa, Ar′ = phenyl, p-tolyl and p-chlorophenyl) were carried out in acetonitrile at 80°C. Results are compared with those of earlier reactions of 1a-e with corresponding sodium aryl thiolates (Ar′SNa). In contrast with the thiolate reactions, those with 7a-c were too slow at room temperature to be useful. Reactions of 1a-c at 80°C gave small amounts of benzene and toluene from la and b, small amounts of diaryl ethers ArOAr′ (9) and thianthrene (Th) and large amounts (90-97%) of 2-(ArS)-2′-(Ar′O)diphenyl sulfide (10). Compared with reactions of 1a-c, those of 1d and e gave larger amounts (10-17%) of 9, lesser amounts (25-30%) of 10 and substantial amounts (42-55%) of 2-[4-(Ar′O)-ArS]-2′-(Ar′O)diphenyl sulfide (12). Small amounts of 1,4-di(Ar′O)benzene (11) were also obtained from reactions of Id and e. Formation of 11 and 12 is preceded by replacement of halogen by Ar′O-. Structures of products 10 and 12 were deduced by comparison with earlier products from thiolate reactions, elemental analyses, mass spectrometry molecular masses and, in the case of 10, the crystal structure of 10d. It is proposed that products 9-12 are formed by nucleophilic reactions of Ar′O- at ipso positions in 1. Copyright
- Qian, Ding-Quan,Shine, Henry J.,Thurston, John H.,Whitmire, Kenton H.
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- Cu(I)-PNF, an organic-based nanocatalyst, catalyzed C-O and C-S cross-coupling reactions
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Peptide nanofiber has been prepared via a self-assembly protocol and decorated with Cu(I) to prepare a nanostructural catalyst. The catalytic activity of this prepared nanomaterial (Cu(I)-PNF) was examined in C-O and C-S cross-coupling reactions. Compared with conventional copper-ligand catalytic systems, CuNP-PNF has unique advantages such as water solubility, high efficiency, and low cost, which makes it a highly efficient and beneficial catalyst to reuse in cross-coupling reactions.
- Taherinia, Zahra,Ghorbani-Choghamarani, Arash
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- An efficient and regioselective monobromination of electron-rich aromatic compounds using catalytic hypervalent iodine(III) reagent
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An efficient and regioselective monobromination of electron-rich aromatic compounds is reported in which iodobenzene is used as the recyclable catalyst in combination with m-chloroperbenzoic acid as the terminal oxidant. The bromination of electron-rich aromatic compounds with lithium bromide was fast in tetrahydrofuran at room temperature, providing regioselective monobrominated products in good yields.
- Zhou, Zhongshi,He, Xuehan
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- Diaza crown-type macromocycle (kryptofix 22) functionalised carbon nanotube for efficient Ni2+ loading; A unique catalyst for cross-coupling reactions
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Raising the capability of supporting and suppressing the leaching possibility to a very insignificant level has still remained challenging for some class of transition metals, i.e. Ni2+. Here we present the covalent functionalisation of macrocyclic ligand, 4,13-diaza-18-crown-6 (kryptofix 22), on the surface of carbon nanotube (CNT), leading to a unique adsorptive capability for supporting Ni2+. This material was incorporated as a promising catalyst in coupling reactions including C[sbnd]C, CN, and CO[sbnd][sbnd] cross-coupling reactions. We demonstrate that the kryptofix 22 functionalisation on the surface of CNT has a key role in the enhancement of the adsorption capability Ni2+ and subsequent catalytic activity. We further prove that this ligand causes a significant boost in the recyclability of the reactions due to the extremely trivial Ni2+ leaching from the CNT's surface during the reactions.
- Aalinejad, Michael,Doustkhah, Esmail,Pesyan, Nader Noroozi
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- Synthesis of arylbromides from arenes and Nbromosuccinimide bromosuccinimide (NBS) in acetonitrile - A convenient method for aromatic bromination
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Regioselective and chemoselective electrophilic bromination of a wide series of activated arenes using N-bromosuccinimide (NBS) in acetonitrile occurs readily. Environmentally friendly conditions, large substrate scope, and ease of synthesis enhance the utility of this method over other electrophilic bromination conditions.
- Zysman-Colman, Eli,Arias, Karla,Siegel, Jay S.
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- Recyclable heterogeneous copper oxide on alumina catalyzed coupling of phenols and alcohols with aryl halides under ligand-free conditions
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An efficient alumina-supported CuO-catalyzed O-arylation of phenols and aliphatic alcohols with various aryl as well as heteroaryl halides under ligand-free conditions are reported. This protocol provides a variety of diaryl ether and bis-diaryl ether motifs by reacting different aryl/aliphatic halides with differently substituted phenols and saturated alcohols in the presence of a catalytic amount of CuO on alumina and KOH as a base at moderate temperature under nitrogen atmosphere. The described methodology is simple, straightforward and efficient to afford the cross-coupled products in high yields under ligand-free conditions. The explored catalyst is inexpensive, air-stable and recyclable up to three cycles.
- Swapna, Kokkirala,Murthy, Sabbavarapu Narayana,Jyothi, Mocharla Tarani,Nageswar, Yadavalli Venkata Durga
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- Betti base as an efficient ligand for copper-catalyzed ullmann coupling of phenol with aryl halides
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GRAPHICAL ABSTRACT A simple, general, and highly efficient Betti base ligand has been developed for copper-catalyzed Ullmann coupling of phenol with aryl halides without the protection of an inert atmosphere. The reaction proceeds smoothly in the presence of K2CO3 as the base and dimethylsulfoxide as the solvent. The catalyst was reused several times with no evident loss of catalytic activity and is environmentally friendly.
- Yang, Li,Yang, Qichao,Shi, Jianxin,Wang, Yufang,Zhang, Mingjie
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- Synthesis of diaryl ethers through the copper-catalyzed arylation of phenols with aryl iodides using KF/Al2O3
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An efficient synthesis of diaryl ethers by the copper-catalyzed arylation of phenols with a variety of aryl iodide susing KF/Al2O3 as a suitable base and CuI and 1,3 diphenyl-1,3 propandione as the catalyst is described. Copyright Taylor & Francis Group, LLC.
- Hosseinzadeh, Rahman,Tajbakhsh, Mahmood,Mohadjerani, Maryam,Rezaei, Parizad,Alikarami, Mohammad
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- Synthetic Methods and Reactions; 127. Regioselective para Halogenation of Phenols, Phenol Ethers and Anilines with Halodimethylsulfonium Halides
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Halodimethylsulfonium halides are efficient regioselective para halogenating agent for activated aromatics, such as phenol, anisole, diphenyl ether and N-alkylanilines.Dihalo and monohalo derivatives of diphenyl ethers were obtained depending upon the reaction conditions.Aniline itself is not suitable in the reaction due to the strong complexation of the lone electron pair of nitrogen with the sulfonium reagent.
- Olah, George A.,Ohannesian, Lena,Arvanaghi, Massoud
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- Palladium nanoparticles supported on silica diphenylphosphinite as efficient catalyst for C-O and C-S arylation of aryl halides
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Silica diphenylphosphinite (SDPP) can be easily obtained through direct phosphorylation of silica gel. Further reaction of SDPP with Pd(II) produces nano Pd(0)/SDPP. This nano Pd(0) catalyst exhibits excellent reactivity for the C-O and C-S arylation of different aryl iodides, bromides and chloride with phenols and thiophenols. This heterogeneous catalyst shows excellent recyclability and can be easily recovered and reused for several runs. Copyright
- Iranpoor, Nasser,Firouzabadi, Habib,Rostami, Abed
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- Preparation of carbon nanotube-supported α-Fe2O 3@CuO nanocomposite: A highly efficient and magnetically separable catalyst in cross-coupling of aryl halides with phenols
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Herein, we introduce the first magnetic CuO nanoparticles based on carbon nanotubes as a highly intriguing magnetic catalyst in Ullmann-type coupling of aryl halides with phenols. Two facile procedures were used for the preparation of this magnetically separable catalytic system. Having been treated with FeSO4 and then H2O2, nanotubes accommodated the resulting iron hydroxides on the walls. The resulting nanocomposite was then exposed to argon atmosphere at 450°C giving rise to a carbon nanotube-supported α-Fe2O3 compound. Ultimately, copper acetate was hydrolysed in the presence of CNT supported α-Fe 2O3 at 100°C and our novel catalyst was gained. Some spectroscopic and microscopic techniques such as Infrared spectroscopy (IR), X-ray diffraction spectroscopy (XRD), Vibrational sample magnetometry (VSM), Brunauer-Emmett-Teller (BET), Barrett-Joyner-Halenda (BJH), Inductively coupled plasma (ICP), Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) corroborated the structure of the catalyst. The catalyst synthesized showed good activity in C-O cross coupling reactions affording the highest rate of completion. Magnetic feature of the catalyst helped facile separation of it from the reaction medium. The catalyst could also be reused up to six times without any loss of its activity.
- Saberi, Dariush,Sheykhan, Mehdi,Niknam, Khodabakhsh,Heydari, Akbar
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- Regioselective Copper-Catalyzed Boracarboxylation of Vinyl Arenes
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Regioselective copper-catalyzed boracarboxylation of vinyl arenes with bis(pinacolato)diboron and carbon dioxide has been achieved. New boron-functionalized α-aryl carboxylic acids, including nonsteroidal anti-inflammatory drugs (NSAIDs), are obtained in moderate to excellent yields. The synthetic utility of the transformation was shown through subsequent derivatization of the carbon-boron bond yielding formal hydroxy- and fluorocarboxylation products as well as anionic difluoroboralactones.
- Butcher, Trevor W.,McClain, Edward J.,Hamilton, Tyler G.,Perrone, Trina M.,Kroner, Kayla M.,Donohoe, Gregory C.,Akhmedov, Novruz G.,Petersen, Jeffrey L.,Popp, Brian V.
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- Direct and regioselective iodination and bromination of benzene, naphthalene and other activated aromatic compounds using iodine and bromine
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Direct and regioselective iodination and bromination of benzene, naphthalene and other activated aromatic compounds with iodine and bromine or their sodium salts proceed well in the presence of Fe(NO3) 3·1.5N2O4/charcoal in CH 2Cl2 at room temperature.
- Firouzabadi,Iranpoor,Shiri
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- Synthesis and characterization of MCM-41-Biurea-Pd as a heterogeneous nanocatalyst and using its catalytic efficacy in C–C, C–N and C–O coupling reactions
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MCM-41-Biurea-Pd is introduced as a new, heterogeneous and reusable catalyst for C–C and C–heteroatom bond formation between various aryl halides, phenols and amines, in the presence of Ph3SnCl (Stille reaction) in PEG-400 as a green solvent at room temperature. The structure of the functionalized MCM-41 was analysed using various techniques.
- Batmani, Hana,Noroozi Pesyan, Nader,Havasi, Forugh
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- Ligand- and Counterion-Assisted Phenol O-Arylation with TMP-Iodonium(III) Acetates
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High reactivity of trimethoxyphenyl (TMP)-iodonium(III) acetate for phenol O-arylation was achieved. It was first determined that the TMP ligand and acetate anion cooperatively enhance the electrophilic reactivity toward phenol oxygen atoms. The proposed method provides access to various diaryl ethers in significantly higher yields than the previously reported techniques. Various functional groups, including aliphatic alcohol, boronic ester, and sterically hindered groups, were tolerated during O-arylation, verifying the applicability of this ligand- and counterion-assisted strategy.
- Kikushima, Kotaro,Miyamoto, Naoki,Watanabe, Kazuma,Koseki, Daichi,Kita, Yasuyuki,Dohi, Toshifumi
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supporting information
p. 1924 - 1928
(2022/03/27)
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- Synthesis and characterization of nano-cellulose immobilized phenanthroline-copper (I) complex as a recyclable and efficient catalyst for preparation of diaryl ethers, N-aryl amides and N-aryl heterocycles
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Functionalized nanocellulose was prepared and employed for immobilization of phenanthroline-copper(I) complex to afford cellulose nanofibril grafted heterogeneous copper catalyst [CNF-phen-Cu(I)]. This nanocatalyst was well characterized using FT-IR, NMR, XRD, CHNS, AAS, TGA, EDX and SEM. The activities of the synthesized catalyst were examined in the synthesis of diaryl ethers via C-O cross-coupling of phenols and aryl iodides, as well as, the preparation of N-aryl amides and N-aryl heterocycles through C-N cross-coupling of amides and N-H heterocycle compounds with aryl halides. In this trend, various substrates containing electron-donating and electron-withdrawing groups were exploited to evaluate the generality of this catalytic protocol. Accordingly, the catalyst demonstrated remarkable catalytic efficiency for both C-N and C-O cross-coupling reactions, thereby resulting in good to excellent yields of the desired products. Furthermore, the recoverability experiments of the catalyst showed that it can be readily retrieved by simple filtration and successfully reused several times with negligible loss of its catalytic activity.
- Aghili, Nora,Hosseinzadeh, Rahman,Mavvaji, Mohammad
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- Direct bromodeboronation of arylboronic acids with CuBr2 in water
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An efficient and practical method has been developed for the preparation of aryl bromides via the direct bromodeboronation of arylboronic acids with CuBr2 in water. This strategy provides several advantages, such as being ligand-free, base-free, high yielding, and functional group tolerant.
- Tang, Yan-Ling,Xia, Xian-Song,Gao, Jin-Chun,Li, Min-Xin,Mao, Ze-Wei
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supporting information
(2021/01/05)
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- L-Proline N-oxide dihydrazides as an efficient ligand for cross-coupling reactions of aryl iodides and bromides with amines and phenols
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A novel catalytic system based on L-proline N-oxide/CuI was developed and applied to the cross-coupling reactions of various N- and O- nucleophilic reagents with aryl iodides and bromides. This strategy featured in the employment of an-proline derived dihydrazides N-oxide compound as the superior supporting ligand. By using this protocol, a variety of products, including N-arylimidazoles, N-arylpyrazoles, N-arylpyrroles, N-arylamines, and aryl ethers, were synthesized with up to 99% yield.
- Ding, Zhiqiang,Nie, Nan,Chen, Tian,Meng, Lingxin,Wang, Gongshu,Chen, Zhangpei,Hu, Jianshe
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supporting information
(2020/12/21)
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- Base-Mediated O-Arylation of Alcohols and Phenols by Triarylsulfonium Triflates
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A mild and efficient protocol for O-arylation of alcohols and phenols (ROH) by triarylsulfonium triflates was developed under transition-metal-free conditions. Various alcohols, including primary, secondary and tertiary, and phenols bearing either electron-donating or electron-withdrawing groups on the aryl rings were smoothly converted to form the corresponding aromatic ethers in moderate to excellent yields. The reactions were conducted at 50 or 80 °C for 24 h in the presence of a certain base and showed good functional group tolerance. The base-mediated arylation with asymmetric triarylsulfonium salts could selectively transfer the aryl groups of sulfoniums to ROH, depending on their inherent electronic nature. The mechanistic studies revealed that the reaction might proceed through the nucleophilic attack of the in situ formed alkoxy or phenoxy anions at the aromatic carbon atoms of the C?S bonds of triarylsulfonium cations to furnish the target products.
- Ming, Xiao-Xia,Tian, Ze-Yu,Zhang, Cheng-Pan
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supporting information
p. 3370 - 3379
(2019/11/03)
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- Ni-Catalyzed Reductive Cyanation of Aryl Halides and Phenol Derivatives via Transnitrilation
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Herein, we report a Ni-catalyzed reductive coupling for the synthesis of benzonitriles from aryl (pseudo)halides and an electrophilic cyanating reagent, 2-methyl-2-phenyl malononitrile (MPMN). MPMN is a bench-stable, carbon-bound electrophilic CN reagent that does not release cyanide under the reaction conditions. A variety of medicinally relevant benzonitriles can be made in good yields. Addition of NaBr to the reaction mixture allows for the use of more challenging aryl electrophiles such as aryl chlorides, tosylates, and triflates. Mechanistic investigations suggest that NaBr plays a role in facilitating oxidative addition with these substrates.
- Mills, L. Reginald,Graham, Joshua M.,Patel, Purvish,Rousseaux, Sophie A. L.
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supporting information
p. 19257 - 19262
(2019/12/02)
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- Thermal Stability of 4-tert-Butyl Diphenyl Oxide
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Abstract: In the temperature range of 703–763 K, the thermal stability of 4-tert-butyl diphenyl oxide (4?TBDPO) has been studied, the components of the thermolysis reaction mass have been identified, a kinetic model of the process has been proposed, and the rate constants and parameters of the Arrhenius equation for all reactions under consideration have been calculated. The predominant role of isomerization transformations of 4-TBDPO has been found. A mechanism for the radical isomerization of the tert-butyl substituent has been proposed.
- Shakun,Nesterova,Tarazanov,Spiridonov
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p. 2123 - 2130
(2019/11/11)
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- Anthracene compound, preparing method of anthracene compound and organic light-emitting device
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The invention provides an anthracene compound. The anthracene compound has a structure in the formula (I), wherein Q is the C1-60 alkyl group or the C6-60 aryl group or the C5-60 condensed ring group or the C5-60 heterocyclic group; Ar is the C6-60 aryl group or the C5-60 condensed ring group or the C5-60 heterocyclic group; and Ar1 is H, the C1-60 alkyl group, the C1-60 alkoxy group, the C1-60 ether group, the C6-60 aryl group, the C6-60 condensed ring group, the C6-60 heterocyclic group and the C6-60 arylamine group. Compared with the prior art, the anthracene compound is connected with an aromatic compound through anthracene, and the Q, Ar and Ar1 groups are introduced, so that a device emits blue light after the organic compound is applied to the organic light-emitting device; and meanwhile, the means that the above groups are used for adjusting the light-emitting wavelength is adopted, the light-emitting efficiency of the organic light-emitting device is high, and the service life is long.
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Paragraph 0121-0126
(2017/05/02)
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- Copper immobilized on magnetite nanoparticles coated with ascorbic acid: An efficient and reusable catalyst for C─N and C─O cross-coupling reactions
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In a continuation of using magnetic nanoparticle (MNP)-supported catalysts, ascorbic acid (readily available, very safe and with strong affinity to MNPs) was used instead of the commonly used silica layer coating. This hybrid was used for immobilizing copper nanoparticles to produce Cu/ascorbic acid@MNPs catalyst. The catalyst was characterized and used in carbon–oxygen and carbon–nitrogen (various substrates) cross-coupling reactions in aqueous media and at room temperature with excellent product yields. Furthermore, the catalyst could be quickly and completely recovered using an external magnetic field and reused for six reaction cycles without significant change in catalytic activity.
- Hajipour, Abdol R.,Check, Maryam,Khorsandi, Zahra
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- Preparation method of 4-bromodiphenyl ether
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The invention provides a preparation method of 4-bromodiphenyl ether. The preparation method specifically comprises the following steps: adding a diphenyl ether-dichloroethane solution into a reaction container, dropwise adding bromine at a temperature of -5 DEG C to 0 DEG C, stirring at the controlled temperature of -5 DEG C to 0 DEG C for 1 to 2 hours, dropwise adding a hydrogen peroxide serving as a catalyst, controlling the dropwise adding to be completed within 0.5 to 1 hour, after the dropwise adding is completed, heating to 25 DEG C, controlling the temperature at 25 to 30 DEG C for reaction for 24 to 48 hours, and quenching with a sodium hydrogen sulfite aqueous solution with the mass concentration of 15 percent; washing with water for phase separation: recycling an inorganic phase, performing coarse steaming on an organic phase to recycling dichloroethane serving as a solvent, performing reduced pressure distillation on a coarse product, recycling and indiscriminately using a front distillate serving as a raw material, and recycling a middle distillate which is the 4-bromodiphenyl ether. The preparation method of the 4-bromodiphenyl ether is simple in process, and the product is high in purity, yield and quality and low in cost; the purity of the 4-bromodiphenyl ether is 98.0 percent, and the yield is 78 percent.
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Paragraph 0030
(2017/09/01)
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- Synthesis method of (s)-1-(4-diphenyl ether)-2-hydroxy-3-chloropropane
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The invention provides a synthesis method of (s)-1-(4-diphenyl ether)-2-hydroxy-3-chloropropane. The synthesis method comprises the following steps of (1) generating 4-bromodiphenyl ether by using diphenyl ether and bromine under catalysis of hydrogen peroxide; (2) adding 4-bromodiphenyl ether, a solvent A and magnesium wires into a reaction vessel in an atmosphere of high-pure nitrogen, raising the temperature to 25-40 DEG C and stirring rapidly to induce Grignard reaction, dripping a solution of 4-bromodiphenyl ether-solvent A, and continuing reacting for 2 hours; and (3) reducing the temperature of a Grignard reagent to 0-5 DEG C, adding a composite coupling agent and a solution of S-epichlorohydrin-solvent A for reaction, pouring a reaction solution into dilute sulfuric acid, taking the upper layer and performing reduced pressure distillation so as to recycle the solvent A, adding residue into water, cooling and performing suction filtration, and drying a wet product to obtain a final product. The synthesis method is easy to operate, the product yield and purity are high, and no solid waste is generated in a production process, so that the synthesis method has higher economic feasibility and is applicable to industrial production.
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Paragraph 0036; 0039; 0042; 0045; 0048; 0051
(2017/08/31)
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- Platinum(II) cyclometallates featuring broad emission bands and their applications in color-tunable OLEDs and high color-rendering WOLEDs
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Two phosphorescent platinum(ii) cyclometallated complexes with phenoxy groups (1 and 2) have been developed. The modified organic ligands derived by combining the phenoxy moiety and 2-phenylpyridine conferred them with a more flexible structure, leading to superior intermolecular interaction properties of the resulting Pt(ii) metallophosphors. Because of the excimer formation induced by Pt(ii) complexes 1 and 2, the emission color can be tuned over a wide range from cyan to orange by simply increasing the concentration of the Pt(ii) metallophosphors. Inspired by their broad emission band, color tunability and outstanding electroluminescence (EL) performance, these two Pt(ii) phosphors complemented with blue fluorescent emitter 4,4′-bis(9-ethyl-3-carbazovinylene)-1,1′-biphenyl (BCzVBi) were employed in manufacturing high color-rendering white organic light-emitting devices (WOLEDs). In such simple two-emitter systems, 1-based WOLEDs exhibited reasonable EL performance with an external quantum efficiency (ηext) of 11.7%, luminance efficiency (ηL) of 29.1 cd A-1, power efficiency (ηp) of 16.9 lm W-1 and color rendering index (CRI) of 77, whereas 2-based WOLEDs demonstrated an ηext of 10%, ηL of 21.7 cd A-1, ηp of 10.7 lm W-1 and CRI of 88.
- Tan, Guiping,Chen, Shuming,Siu, Chi-Ho,Langlois, Adam,Qiu, Yongfu,Fan, Hongbo,Ho, Cheuk-Lam,Harvey, Pierre D.,Lo, Yih Hsing,Liu, Li,Wong, Wai-Yeung
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p. 6016 - 6026
(2016/07/06)
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- A counteranion triggered arylation strategy using diaryliodonium fluorides
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A mild and transition metal-free counteranion triggered arylation strategy has been developed using diaryliodonium fluorides. The fluoride counteranion within the hypervalent iodonium species displays unusual reactivity that activates a phenolic O-H bond leading to electrophilic O-arylation. A wide range of phenols and diaryliodonium salts are compatible with this transformation under remarkably mild conditions. Furthermore, we pre-empt the wider implications of this strategy by demonstrating the compatibility of the arylation tactic with latent carbon nucleophiles.
- Chan,McNally,Toh,Mendoza,Gaunt
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p. 1277 - 1281
(2015/02/05)
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- Rapid, photocatalytic, and deep debromination of polybrominated diphenyl ethers on Pd-TiO2: Intermediates and pathways
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Titanium dioxide with surface-loaded palladium (Pd-TiO2) was able to easily remove all ten bromine atoms from decabromodiphenyl ether (BDE209) within 1 h under the irradiation of sunlight or an artificial light source. By contrast, fewer than three bromine atoms were eliminated on the pristine TiO2 even with prolonged irradiation (5 h). During the photocatalytic debromination, moreover, the formed BDE intermediates exhibited a significant difference between the Pd-TiO2 and pristine TiO 2 systems, and much less position selectivity for the debromination on Pd-TiO2 was observed than that on the pristine TiO2 surface. For another polybrominated diphenyl ether (BDE15), pristine TiO 2 was incapable of its photocatalytic reduction, whereas the loading of Pd enabled its debromination to diphenyl ether within 20 min. In addition, an evident induction period appeared in the photocatalytic debromination of BDE15 on Pd-TiO2. The experiments imply that the Pd-cocatalyzed effect changes significantly the photocatalytic reductive debromination pathways.
- Li, Lina,Chang, Wei,Wang, Ying,Ji, Hongwei,Chen, Chuncheng,Ma, Wanhong,Zhao, Jincai
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p. 11163 - 11170,8
(2015/02/02)
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- Synthesis of ionic-liquid-supported diaryliodonium salts
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The synthesis of ionic-liquid-supported diaryliodonium salts is described. The synthesis is simple and practical, and the ionic liquid products require no chromatographic purification. The ionic-liquid-supported diaryliodonium salts are quite stable, and they did not show any sign of decomposition or loss of reactivity, even after being stored for one month at 5 °C. The reactivity of these salts was explored in the phenylation of substituted phenols and carboxylic acids, and the corresponding diaryl ethers and aryl esters, respectively, were synthesized in good to excellent yields and with high purities.
- Kumar Muthyala, Manoj,Choudhary, Sunita,Pandey, Khima,Shelke, Ganesh M.,Jha, Mukund,Kumar, Anil
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p. 2365 - 2370
(2014/04/17)
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- Chemoselective and ligand-free synthesis of diaryl ethers in aqueous medium using recyclable alumina-supported nickel nanoparticles
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An economical and eco-compatible ligand-free protocol for the synthesis of diaryl ethers has been developed using easily accessible alumina-supported nickel nanoparticles as a stable recyclable heterogeneous catalyst in aqueous medium along with a surfactant (SDS) and a mild base (K2CO3). Various sensitive functional groups like allyl, alkoxycarbonyl, formyl, oxo, chloro, bromo, amine and nitro were tolerated in the aforesaid method. Excellent chemoselectivity was demonstrated through competition experiments.
- Ghatak, Avishek,Khan, Sagar,Roy, Rimi,Bhar, Sanjay
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supporting information
p. 7082 - 7088
(2015/02/02)
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- Highly active recyclable heterogeneous Pd/ZnO nanoparticle catalyst: Sustainable developments for the C-O and C-N bond cross-coupling reactions of aryl halides under ligand-free conditions
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Efficient Pd supported on ZnO nanoparticles for the ligand-free O-arylation and N-arylation of phenols and various N-H heterocycles with aryl chlorides, bromides, and iodides were readily synthesized and characterized. The amount of palladium on ZnO is 9.84 wt% (0.005 g of the catalyst contains 462 × 10-8 mol% of Pd) which was determined by ICP analysis. This nano sized Pd/ZnO with an average particle size of 20-25 nm and specific surface area 40.61 m2 g-1 was used as a new reusable heterogeneous catalyst for the formation of C-O and C-N bonds in organic synthesis. This protocol gives the arylated product in satisfactory yields without any N2 or Ar flow. The catalyst can be recovered and recycled several times without marked loss of activity.
- Hosseini-Sarvari, Mona,Razmi, Zahra
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p. 44105 - 44116
(2014/12/10)
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- First palladium-catalyzed denitrated coupling reaction of nitroarenes with phenols
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The first palladium-catalyzed protocol for the denitrated coupling reaction of nitroarenes with phenols has been developed, achieving unsymmetrical diaryl ethers in moderate to excellent yields. The cyclopalladated ferrocenylimine (catalyst Ic) exhibited highly catalytic activity for this transformation with low catalyst loading (0.75 mol%) and short reaction time (2 h). The efficiency of this reaction was demonstrated by its compatibility with a range of groups. Moreover, the rigorous exclusion of air or moisture was not required in these transformations. Copyright
- Wang, Hailei,Yu, Ajuan,Cao, Aijuan,Chang, Junbiao,Wu, Yangjie
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p. 611 - 614
(2013/10/21)
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- Microwave-assisted synthesis of nonsymmetrical aryl ethers using nitro-arenes
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An efficient, microwave-assisted ligand-free, catalyst-free synthetic method for nonsymmetrical diaryl ethers has been developed by using nitroarenes. A variety of phenols and nitroarenes was scanned by using this method to produce nonsymmetrical aryl ethers. The newly developed method is an ecofriendly and cost-effective approach to synthesize nonsymmetrical aryl ethers.
- Sarkate, Aniket P.,Bahekar, Sushilkumar S.,Wadhai, Vijay M.,Ghandge, Ganesh N.,Wakte, Pravin S.,Shinde, Devanand B.
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p. 1513 - 1516
(2013/08/23)
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- Potassium tert-butoxide-mediated synthesis of unsymmetrical diaryl ethers, sulfides and selenides from aryl bromides
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Potassium tert-butoxide mediated carbon-chalcogen C-E (E=O, S and Se) coupling reaction has been studied from aryl bromide and phenol/aryl disulfide/diselenide substrates. A series of unsymmetrical diaryl chalcogenides were accessed from aryl bromide and diaryl dichalcogenide precursors by using 2.5 equiv of potassium tert-butoxide in DMSO at 80 C. Unsymmetrical diaryl ethers were also obtained by using phenol precursors at 40-45 C. Aryl bromides with methyl, trifluoromethyl, methoxy and nitro substituents showed compatibility in the carbon-chalcogen bond forming reaction. 4-Methoxy, methyl, trifluoromethyl substituted bromobenzene substrates gave two regioisomers: 3-substituted and 4-substituted diaryl chalcogenides when reacted with phenols/diaryl disulfides/diselenides. Formation of two regioisomeric diaryl chalcogenides in the reaction mixture suggests that potassium tert-butoxide reacts with bromobenzene to produce benzyne intermediate, which subsequently reacts with diaryl dichalcogenides and finally give a regioisomeric mixture of 4-substituted and 3-substituted diaryl chalcogenides.
- Kumar, Amit,Bhakuni, Bhagat Singh,Prasad, Ch. Durga,Kumar, Shailesh,Kumar, Sangit
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p. 5383 - 5392
(2013/07/04)
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- An Ullmann C-O coupling reaction catalyzed by magnetic copper ferrite nanoparticles
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Herein, an efficient method for the Ullmann C-O coupling reaction between various kinds of phenols and aryl halides, including amino, ketone, cyano, methyl, methoxy, fluoro, chloro and bromo derivatives, is described. The catalyst used, copper ferrite (CuFe2O4) nanoparticles, are easily made, air-stable, and of low cost. The catalyst can be recycled easily just by using an external magnet. Even in the presence of sensitive substituents, the reaction proceeds successfully to provide the desired products in high yields without protection of other functional groups. Copyright
- Yang, Shuliang,Wu, Cunqi,Zhou, Hua,Yang, Yanqin,Zhao, Yongxia,Wang, Chenxu,Yang, Wei,Xu, Jingwei
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supporting information
p. 53 - 58
(2013/03/13)
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- Copper(II) trans-bis-(glycinato): An efficient heterogeneous catalyst for cross coupling of phenols with aryl halides
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Copper(II) trans-bis-(glycinato) complex, easily prepared by the solid state reaction of copper(II) acetate and glycine (trans-[Cu(glyo) 2·H2O]) was found to be an efficient, recyclable, and high yielding catalyst for the Ullmann type synthesis of diaryl ethers via the cross coupling of phenols with aryl halides without using any additives at relatively low reaction temperature. The catalyst could easily be recovered by simple filtration and was reused for several runs with consistent catalytic activity.
- Verma, Sanny,Kumar, Neeraj,Jain, Suman L.
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experimental part
p. 4665 - 4668
(2012/09/05)
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- Chemo-selective copper-catalyzed C-O coupling reactions of phenols with aryl/vinyl halides using enaminone as efficient ligand
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The copper-catalyzed Ullmann C-O coupling reactions between phenols and aryl/vinyl halides have been efficiently performed by employing (E)-3-(dimethylamino)-1-(2-hydroxyphenyl)prop-2-en-1-one, an easily available enaminone, as ligand. This new ligand is advantageous for its easy availability, broad applicability and good efficiency. Copyright 2012 John Wiley & Sons, Ltd. Copyright
- Wan, Jie-Ping,Wang, Chunping,Liu, Yunyun
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experimental part
p. 445 - 447
(2012/09/25)
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- Novel multifunctional organic semiconductor materials based on 4,8-substituted 1,5-naphthyridine: Synthesis, single crystal structures, opto-electrical properties and quantum chemistry calculation
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A series of 4,8-substituted 1,5-naphthyridines (1a-1h) have been successfully synthesised by a Suzuki cross-coupling between 4,8-dibromo-1,5- naphthyridine (4) and the corresponding boronic acids (2a-2h) in the presence of catalytic palladium acetate in yields of 41.4-75.8% and have ben well characterized. They are thermally robust with high phase transition temperatures (above 186 °C). Compounds 1b, 1e and 1f crystallized in the monoclinic crystal system with the space groups P21/c, P21/c and P21/n, respectively. All of them show the lowest energy absorption bands (λmaxAbs: 294-320 nm), revealing low optical band gaps (2.77-3.79 eV). These materials emit blue fluorescence with λmaxEm ranging from 434-521 nm in dilute solution in dichloromethane and 400-501 nm in the solid state. 4,8-Substituted 1,5-naphthyridines 1a-1h have estimated electron affinities (EA) of (2.38-2.72 eV) suitable for electron-transport materials and ionization potentials (IP) of 4.85-5.04 eV facilitate excellent hole-injecting/hole-transport materials properties. Quantum chemical calculations using DFT B3LYP/6-31G* showed nearly identical the lowest unoccupied molecular orbitals (LUMO) of -2.39 to -2.19 eV and the highest occupied molecular orbitals (HOMO) of -5.33 to -6.84 eV. These results demonstrate the 4,8-substituted 1,5-naphthyridines 1a-1h with a simple architecture might be promising blue-emitting (or blue-green-emitting) materials, electron-transport materials and hole-injecting/hole-transport materials for applications for developing high-efficiency OLEDs.
- Wang, Kun-Yan,Chen, Chen,Liu, Jin-Fang,Wang, Qin,Chang, Jin,Zhu, Hong-Jun,Li, Chong
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scheme or table
p. 6693 - 6704
(2012/09/22)
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- Aminoarenethiolato-copper(I) as (pre-)catalyst for the synthesis of diaryl ethers from aryl bromides and sequential C-O/C-S and C-N/C-S cross coupling reactions
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A small library of 2-aminoarenethiolato-copper(I) (CuSAr) complexes was tested as (pre-)catalysts in the arylation reaction of phenols with aryl bromides. These copper(I) (pre-)catalysts are thermally stable, soluble in common organic solvents, and allow reactions of 6 h at 160 °C with low catalyst loadings of 2.5 mol %. Among the (pre-)catalysts screened, 2-[(dimethylamino)methyl]benzenethiolato-copper(I) (1c) led to the best results and provided good to excellent yields of various substituted diaryl ethers. Mechanistic studies showed that at early stages of the C-O coupling reaction the CuSAr complex is converted into CuBr(PhSAr) via selective coupling of the monoanionic arenethiolato ligand with phenyl bromide with formation of CuBr. In addition, the first results are shown involving a multi-component reaction (MCR) protocol for the in situ synthesis of propargylamines and their subsequent conversion involving a C-O cross coupling reaction. Furthermore, two examples of sequential C-O/C-S and C-N/C-S cross coupling reactions have been carried out on the same dihalo-pyridine substrate in a one-pot process with the same (CuSAr) (pre-)catalyst (overall yields 40-80%).
- Sperotto, Elena,Van Klink, Gerard P.M.,De Vries, Johannes G.,Van Koten, Gerard
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experimental part
p. 9009 - 9020
(2011/01/04)
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- Efficient catalytic activity of copper/aluminum hydrotalcite in diaryl ether synthesis
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A simple copper/aluminum hydrotalcite (Cu/Al-HT) catalyzed arylation of phenols with aryl iodides afforded the corresponding diaryl ethers in moderate to excellent yields. This ligand- free Cu/Al-HT catalyzed coupling of aryl iodides with phenols resulted in high yields of diaryl ethers in the absence of an additive. The catalyst was quantitatively recovered from the reaction by simple filtration and reused for a number of cycles. Georg Thieme Verlag Stuttgart New York.
- Sreedhar,Arundhathi,Reddy, M. Amarnath,Kantam, M. Lakshmi
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experimental part
p. 483 - 487
(2009/07/11)
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- A versatile and efficient ligand for copper-catalyzed formation of C-N, C-O, and P-C bonds: Pyrrolidine-2-phosphonic acid phenyl monoester
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A new and readily available bidentate ligand, namely, pyrrolidine-2- phosphonic acid phenyl monoester (PPAPM), has been developed for the copper-catalyzed formation of C-N, C-O, and P-C bonds, and various N-, O-, and P-arylation products were synthesized in good to excellent yields by using the CuI/PPAPM catalyst system. Addition of the PPAPM ligand greatly increases the reactivity of the copper catalyst, and the resulting versatile and efficient catalyst system is of widespread and practical application in cross-coupling reactions.
- Rao, Honghua,Jin, Ying,Fu, Hua,Jiang, Yuyang,Zhao, Yufen
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p. 3636 - 3646
(2008/02/03)
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- Exploiting a basic chemosensitizing pharmacophore hypothesis. Part 1: Synthesis and biological evaluation of novel arylbromide and bicyclic chemosensitizers against drug-resistant malaria parasites
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An exploratory series of novel arylbromide and bicyclic chemosensitizers (modulators) against chloroquine-resistant Plasmodium falciparum were designed and synthesized on the basis of a basic chemosensitizing pharmacophore hypothesis in malaria. ortho-Substituted bromo and biphenyl ether compounds displayed the best activity from the series.
- Chouteau, Franck,Ramanitrahasimbola, David,Rasoanaivo, Philippe,Chibale, Kelly
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p. 3024 - 3028
(2007/10/03)
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- 2-FURANCARBOXYLIC ACID HYDRAZIDES AND PHARMACEUTICAL COMPOSITIONS CONTAINING THE SAME
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The present invention provides 2-furancarboxylic acid hydrazide compounds represented by General Formula(I) below, and prodrugs, physiologically acceptable salts, hydrates, solvates thereof, methods for producing them and pharmaceutical compositions containing them: wherein A is a group represented by Formula (a) or the like: (wherein either R4 or R5 represents cyano, nitro or the like, and the other represents a hydrogen atom or the like); either R1 or R2 represents a group: -D-(X)m-R6 or the like, and the other represents a group: -E-(Y)n-R7, hydrogen atom, aryl or the like; R3 is a hydrogen atom or the like; D and E independently represent aryl; X and Y independently represent 0 or the like; R6 and R7 independently represent alkyl, aryl, arylalkyl or the like; and m and n are independently 0 or 1, provided that the aryl is optionally substituted. Such compounds exhibit a potent antagonistic activity on glucagon receptor and are of use as preventive and/or therapeutic agents for symptoms and diseases in which glucagon is involved.
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- Process for preparation of 4-(4-phenoxyphenoxy) benzoic acid by oxidation of 1-(4-methylphenoxy)-4-phenoxybenzene
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A novel process for preparation of 1-(4-methylphenoxy),4-phenoxybenzene (I) by the nucleophilic substitution route and its oxidation to give 4-(4-phenoxyphenoxy benzoic acid (II), a monomer used for synthesis of speciality thermoplastic polymer.
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- Synthesis and characterization of 32 polybrominated diphenyl ethers
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Polybrominated diphenyl ethers (PBDEs) are widely used as additive flame retardants in, for example, textiles, computers, television sets, and other electrical appliances. present also in humans. The environmental levels of the PBDEs are, however, still in general lower than those of polychlorinated biphenyls (PCBs). However, while the levels of PCBs generally are decreasing, those of the PBDEs are increasing in, for example, human milk. In the present study 32 individual PBDE congeners were synthesized and characterized. Physicochemical parameters including melting points and UV, 1H NMR, and mass spectra are reported Twenty-nine monobrominated to heptabrominated diphenyl ethers were synthesized by the couping between four diphenyliodonium salts and nine phenolates. One tetrabromodiphenyl ether and two hexabromodiphenyl ethers were synthesized by bromination of two different PBDEs. Twenty-one of the PBDEs and two of the iodonium salts, 2,2′,4,4′-tetrabromodiphenyliodonium chloride and 3,3′,4,4′-tatrabromodiphenyliodonium chloride, are to the authors' knowledge described for the first time. These synthesized reference compounds will aid in the identification and quantification of PBDEs present in environmental samples and will allow further assessment of PBDE toxicity.
- Marsh, Goeran,Hu, Jiwei,Jakobsson, Eva,Rahm, Sara,Bergman, Aeke
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p. 3033 - 3037
(2007/10/03)
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- Polar Radicals. 17. On the Mechanism of Iodine Atom Transfer. A 9-I-2 Intermediate
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The atom-transfer reaction of iodine from an aryl iodide to a phenyl radical has been shown to proceed via a 9-I-2 ntermediate.The relative kinetics of the reactions of the intermediate were investigated by studying its mode of decomposition upon formation from the reduction of a series of unsymmetrically substituted diaryliodonium salts.The iodonium salts were reduced by the electron-transfer reactions with several reagents: di-tert-butyl nitroxide, sodium 2,6-di-tert-butylphenylate, and sodium phenylate.The reduction by electron transfer of the iodonium salts by the latter reaction gives high yields of diaryl ethers.The mechanism fo ether formation has been shown to proceed by two mechanistic pathways.For the diaryliodonium salts that have a p-cyano or p-nitro substituent, the ether is formed by a nucleophilic aromatic substitution; however, when the substituents were not strongly electron withdrawing, the mechanism resulting in ether formation involved electron transfer from the phenylate anion to the iodonium salt to form the phenoxy radical and a 9-I-2 intermediate.The intermediate decomposes to an aryl radical and an aryl iodide.The ether is formed from the efficient coupling of the aryl radical and the phenoxy radical.
- Tanner, Dennis D.,Reed, Darwin W.,Setiloane, B.P.
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p. 3917 - 3923
(2007/10/02)
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