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991.
Immobilization of nickel ions onto the magnetic nanocomposite based on cross‐linked melamine groups: Effective heterogeneous catalyst for N‐Arylation of Arylboronic acids 下载免费PDF全文
Ali Pourjavadi Nahid Keshavarzi Firouz Matloubi Moghaddam Seyed Hassan Hosseini 《应用有机金属化学》2018,32(2)
A new magnetic heterogeneous catalyst was synthesized by immobilization of nickel ions onto a cross‐linked polymeric nanocomposite composed of cyanuric chloride, ethylenediamine and functionalized magnetic nanoparticles. The resulting nitrogen rich support was capable of adsorbing large amounts of nickel ions (1.20 mmol g?1). The synthesized catalyst was characterized using AAS, TEM, FT‐IR, EDX, TGA, SEM, BET and XRD techniques. The performance of the prepared catalyst was investigated in the C‐N coupling of arylamines with aryl boronic acids. The reaction was carried out under a mild condition and good to moderate to good yields of products was obtained using only 5.0 mol% of the catalyst. The catalyst was easily recovered and reused for at least 7 times without any significant loss of its activity. 相似文献
992.
Recyclable and reusable NiCl2(PPh3)2/CuI/PEG‐400/H2O system for the sonogashira coupling reaction of aryl iodides with alkynes 下载免费PDF全文
A stable and highly efficient NiCl2(PPh3)2/CuI/PEG‐400/H2O catalytic system for the Sonogashira reaction has been developed. In the presence of NiCl2(PPh3)2 and CuI, the coupling reaction of aryl iodides with terminal alkynes was carried out smoothly in a mixture of poly(ethylene glycol) (PEG‐400) and water at 100°C with K2CO3 as base to afford a variety of arylacetylenes in good to excellent yields. The isolation of the products was readily performed by extraction with petroleum ether, and the NiCl2(PPh3)2/CuI/PEG‐400/H2O system could be easily recycled and reused six times without significant loss of catalytic activity. Our system not only avoids the use of easily volatile organic solvents but also solves the basic problem of catalyst reuse. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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The title compound, [NiL]5[V34O82·8H2O (1, L=5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane), has been synthesized under hydrothermal conditions and structurally characterized by EA, IR, XPS, TG and single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group C2/c with a=33.061(4), b=15.3457(17), c=33.902(4), β=101.930(2)°, Mr=4904.08, V=16828(3)3 , Z=4, Dc=1.936 g/cm3 , F(000)=9832, μ=2.425 mm-1 , the final R=0.0402 and wR=0.0969. The mixed valence vanadium clusters of [V34O82]10- bridges [NiL]2+ to form a one-dimensional chain in 1. To the best of our knowledge, the title complex is the first example of organic-inorganic hybrid material involving the largest vanadium cluster of [V34O82]10-. 相似文献
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A new β‐ketoimine ligand was prepared through traditional condensation of 2‐acetylcyclohexanone with 1‐naphthylamine. Consequently, the new moisture‐ and air‐stable bis(β‐ketoamino)nickel(II) complex Ni[2‐CH3C(O)C6H8(NAr)]2 (Ar = naphthyl) was synthesized and characterized. The solid‐state structures of the ligand and complex have been determined by single‐crystal X‐ray diffraction. Additionally, the new complex is a highly active catalyst precursor for polymerization of norbornene in combination with methylaluminoxane. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Cover Picture: Controlled Synthesis of Nanoporous Nickel Oxide with Two‐Dimensional Shapes through Thermal Decomposition of Metal–Cyanide Hybrid Coordination Polymers (Chem. Eur. J. 9/2015) 下载免费PDF全文
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The dechlorination of alkyl and aryl (poly)chlorides is rapid and complete upon treatment with a new reduction system consisting of NaH as reagent, Ni–Al clusters as catalyst and t‐BuOH as catalytic co‐factor. The high efficiency of this combination is presumed to be due to the stabilization of the subnanometre nickel particles formed during reduction by the in‐situ‐generated alkoxide. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献