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1.
Mohamed Shaker S. Adam 《应用有机金属化学》2018,32(4)
Three novel paramagnetic metal complexes (MH2ID) of Ni2+, Cu2+ and VO2+ ions with 3‐hydroxy‐3,3’‐biindoline‐2,2’‐dione (dihydroindolone, H4ID) were synthesized and characterized by different spectroscopic methods. The ligand (H4ID) was synthesized via homocoupling reaction of isatin in presence of phenylalanine in methanol. Complexation of low valent Ni2+, Cu2+ ions and high valent VO2+ ions with H4ID carried out in 1: 2 molar ratios. A comparison in the catalytic potential of paramagnetic complexes of low and high valent metal ion was explored in the oxidation processes of cis‐cyclooctene, benzyl alcohol and thiophene by an aqueous H2O2, as a green terminal oxidant, in the presence and absence of acetonitrile, as an organic solvent, at 85 °C. NiH2ID, CuH2ID and VOH2ID show good catalytic activity, i.e. good chemo‐ and regioselectivity. VOH2ID has the highest catalytic potential compared to both Ni2+‐ and Cu2+‐species in the same homogenous aerobic atmosphere. Catalytic oxidation of other alkenes and alcohols was also studied using NiH2ID, CuH2ID or VOH2ID as a pre‐catalyst by an aqueous H2O2. A mechanistic pathway for those oxidation processes was proposed. 相似文献
2.
Water‐soluble 2N2O–Cu(II) complexes were synthesized and used for the catalytic oxidation of benzylic alcohols to the corresponding aldehydes in pure water resulting in high yields of up to 94%. Importantly, the catalytic system exhibits a wide substrate scope, high functional group tolerance and can be reused directly for subsequent reaction cycles. Using this catalytic system, the product 4‐methylbenzaldehyde can be produced on a multi‐gram scale and in the complete absence of any organic solvent, surfactant or phase transfer reagent. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
3.
Square planar mixed ligand complexes of the type [CuLL′] where L = 5-chlorosalicylaldehyde and L′ = acetoacetanilide, have
been synthesized on treatment with ammonia. Amine exchange of the above Schiff base complexes has been carried out on treatment
with different amines. The reaction with ethanol amine is quite interesting compared to other amines. It reacts with 5-chlorosalicylaldehyde
to form a Schiff base, while the β-diketone part is removed in the complex formation. All the complexes were characterized
by elemental analysis, spectral studies, magnetic measurement, TLC, and conductane. 相似文献
4.
《Journal of Coordination Chemistry》2012,65(20):3511-3518
Copper(II) complexes [Cu(L)2]?·?nH2O, where L is 3-(p-X-)-4-hydroxy-l,2-naphthoquinone (for L1, X?=?H; L2, X?=?CH3; L3, X?=?Cl; L4, X?=?Br; and L5, X?=?NO2), have been synthesized and characterized by analytical, electrochemical, spectroscopic (IR, UV-Vis, ESR, and 1H NMR), and magnetic methods. From the data obtained, square-planar geometry has been assigned for all the complexes. [CuL1]?·?H2O exhibits catalytic activity for oxidation of benzyl alcohol, piperonyl alcohol, and cinnamyl alcohol into their respective aldehydes in the presence of H2O2 as co-oxidant and in CH3CN and H2O as solvents at room temperature. 相似文献
5.
On encapsulation inside the supercage of zeolite‐Y planar Cu (II)–Schiff base complexes show the modified structural, optical and functional properties. The electronic effect of the different substituent groups present in the catalyst plays the decisive role towards their reactivity in the homogeneous phase but after the encapsulation in zeolite Y, reactivity is mainly governed by the molecular dimensions of the guest complexes rather than the electronic factor of the substituent groups attached on them. These systems are well characterized with the help of different characterization tools like XRD analysis, SEM ‐ EDX, AAS, FTIR, XPS, DSC, TGA, BET and UV–Visible spectroscopy and the comparative optical and catalytic studies have provided a rational explanation of enhanced reactivity of zeolite encapsulated metal complexes for various oxidation reactions compared to their corresponding solution states. 相似文献
6.
Z. P. Pai P. V. Berdnikova A. G. Tolstikov O. N. Roor T. B. Khlebnikova N. K. Gusarova S. F. Malysheva N. I. Ivanova B. A. Trofimov 《Reaction Kinetics and Catalysis Letters》2008,94(2):319-326
The prospects of using bifunctional homogeneous metal-complex catalysts based on peroxo-polyoxotungstates with organic ligands
(tertiary phosphine oxides) were exemplified by oxidation of benzyl alcohol and cyclooctene with hydrogen peroxide in two-phase
systems (organic phase — liquid phase). 相似文献
7.
Brunilde Castano Tommaso Pedrazzini Massimo Sisti Emma Gallo Fabio Ragaini Nicola Casati Alessandro Caselli 《应用有机金属化学》2011,25(11):824-829
The synthesis and characterization of copper(I) complexes of the novel pyridine‐containing macrocyclic ligand (PC‐L) and their use as catalysts in the Henry reaction are reported. The pyridine‐based 12‐membered tetraaza macrocyclic (PC‐L) ligand 1 can be obtained in good overall yield (85%) from commercially available starting materials. The Cu(I) complexes showed good catalytic activities in the Henry reaction of different aldehydes and nitroalkanes. Remarkable diastereoselectivity was observed when isatine was reacted with nitroethane under catalytic conditions. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
8.
9.
Aromatic hydrocarbons are oxidized with hydrogen peroxide in the presence of catalytic amounts of VO3
– and pyrazine-2-carboxylic acid into phenols (provided excess hydrocarbon is used) or into quinones (at high H2O2 concentrations). 2-Propanol, ethanol, cyclohexanol, and benzyl alcohol are transformed into the corresponding aldehydes and ketones under the same conditions (without a solvent or in MeCN).For part 1, see ref. 1.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1394–1396, August, 1993. 相似文献
10.
Chitosan, a natural polymer, bound Schiff base copper complexes CT‐She‐Cu, CT‐o‐Bel‐Cu, CT‐m‐Bel‐Cu were prepared and characterize by inductively coupled plasma (ICP), FT‐IR and X‐ray photoelectron spectroscopy (XPS). Their catalytic activity in the oxidation of cyclohexene with molecular oxygen was studied. All the complexes have catalytic activity and the main oxidation products are 2‐cyclohexene‐ol, 2‐cyclohexene‐one and cyclohexene hydroperoxide, which were measured by gas chromatography/mass spectroscopy (GC/MS) and GC/IR. CT‐m‐Bel‐Cu was selected to study the influence of reaction temperature, amount of catalyst and additives such as acid and base on the oxidation of cyclohexene systematically. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
11.
Five new metal‐organic frameworks (MOFs) of the general composition [Ph3SnCu(CN)2·L], where L=pyrazine (pyz) ( 1 ), methylpyrazine (mepyz) ( 2 ), 4,4′‐bipyridine (bpy) ( 3 ), trans‐1,2‐bis(4‐pyridyl)ethene (tbpe) ( 4 ) or 1,2‐bis(4‐pyridyl)ethane (bpe) ( 5 ), have been synthesized and characterized to test their potential applications as catalysts. The structures of the MOFs 1 – 5 mainly consist of Cu(CN)2 building blocks connected by the Ph3Sn cations and the bipodal ligand forming polymeric networks. They exhibit strong fluorescence in the solid state. Also, they are used as heterogeneous catalysts for the degradation of azo‐dyes, metanil yellow (MY) by diluted solution of hydrogen peroxide as oxidant. The reaction is first order with respect to MY dye, while the factors affecting the rate constant of the degradation reaction are investigated. The activation parameters of the reaction have been estimated and a possible mechanism has been proposed. 相似文献
12.
Byung Joo Lee Kimberly S. DeGlopper Tehshik P. Yoon 《Angewandte Chemie (International ed. in English)》2020,59(1):197-202
Methods that enable the direct C?H alkoxylation of complex organic molecules are significantly underdeveloped, particularly in comparison to analogous strategies for C?N and C?C bond formation. In particular, almost all methods for the incorporation of alcohols by C?H oxidation require the use of the alcohol component as a solvent or co‐solvent. This condition limits the practical scope of these reactions to simple, inexpensive alcohols. Reported here is a photocatalytic protocol for the functionalization of benzylic C?H bonds with a wide range of oxygen nucleophiles. This strategy merges the photoredox activation of arenes with copper(II)‐mediated oxidation of the resulting benzylic radicals, which enables the introduction of benzylic C?O bonds with high site selectivity, chemoselectivity, and functional‐group tolerance using only two equivalents of the alcohol coupling partner. This method enables the late‐stage introduction of complex alkoxy groups into bioactive molecules, providing a practical new tool with potential applications in synthesis and medicinal chemistry. 相似文献
13.
Influence of Fluorination on the Conformational Properties and Hydrogen‐Bond Acidity of Benzyl Alcohol Derivatives 下载免费PDF全文
Dr. Elena Bogdan Dr. Guillaume Compain Lewis Mtashobya Prof. Jean‐Yves Le Questel François Besseau Dr. Nicolas Galland Prof. Bruno Linclau Dr. Jérôme Graton 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(32):11462-11474
14.
Three novel copper(II) complexes, [Cu(Gly‐l ‐Val)(HPBM)(H2O)]·ClO4·H2O ( 1 ), [Cu(Gly‐l ‐Val)(TBZ)(H2O)]·ClO4 ( 2 ) and [Cu(Gly‐l ‐Val)(PBO)(H2O)]·ClO4 ( 3 ) (Gly‐l ‐Val = glycyl‐l ‐valine anion, HPBM = 5‐methyl‐2‐(2′‐pyridyl)benzimidazole, TBZ = 2‐(4′‐thiazolyl)benzimidazole, PBO = 2‐(2′‐pyridyl)benzoxazole), have been prepared and characterized with elemental analyses, conductivity measurements as well as various spectroscopic techniques. The interactions of these copper complexes with calf thymus DNA were explored using UV–visible, fluorescence, circular dichroism, thermal denaturation, viscosity and docking analyses methods. The experimental results showed that all three complexes could bind to DNA via an intercalative mode. Moreover, the cytotoxic effects were evaluated using the MTT method, and the antimicrobial activity of these complexes was tested against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The results showed that the activities are consistent with their DNA binding abilities, following the order of 1 > 2 > 3 . 相似文献
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16.
Rong‐Min Wang Nai‐Pu He Yu‐Feng He Yun‐Tao Xie Yun‐Pu Wang Eishun Tsuchida 《先进技术聚合物》2005,16(8):638-641
Water‐soluble low molecular weight chitosan of nanometer level and its copper complexes were prepared, and characterized by IR spectra, elemental analysis and gel permeation chromatography (GPC). The modes and mechanism of these copper complexes interaction with DNA were studied by a fluorescent probe method and electrophoresis analysis. It is suggested that there are electrostatic and intercalation modes of copper complexes interacting with DNA. At first, the cationic complex electrostaticly binds to the negatively charged phosphate backbone of DNA, and then a portion of the complex intercalates between the base pairs on the DNA duplex strand. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
17.
Thermal and/or photochemical conversion of a series of copper(II) complexes containing mixed dithiocarbamato–alcohol ligands, CuII(Et2dtc)+ . . . Y− (Y=ClO4−, NO3−), into CuII(Et2dtc)Cl in chloroalkane/alcohol solutions, where chloroalkane=CCl4, CHCl3 or CH2Cl2 and alcohol=MeOH, EtOH or i-BuOH, proceeds in chloroalkanes. Both reactions follow a similar pathway which is more effective the stronger the acceptor properties of chloroalkanes and the weaker the coordinating abilities of alcohols are. A detailed reaction mechanism is proposed which well fits the experimental results obtained by EPR and UV–VIS spectra and quantum yields. 相似文献
18.
A search for non-cyanide plating baths for copper resulted in the development of alkaline copper complex baths containing
trisodium citrate [TSC] and triethanolamine [TEA]. Voltammetric studies were carried out on platinum to understand the electrochemical
behaviour of these complexes. In TSC solutions, the deposition of copper involves the slow formation of a monovalent species.
Adsorption of this species obeys Langmuir isotherm. In TEA solutions the deposition involves the formation of monovalent ions
obeying the non-activated Temkin isotherm. Conversion of divalent to monovalent copper is also slow. In TEA and TSC alkaline
copper solutions, the predominant species that undergo stepwise reduction contain only TEA ligands. 相似文献
19.
Roza Dimeska Jan Wikaira Garry M. Mockler Ray J. Butcher 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(5):538-544
The structures of three copper‐containing complexes, namely (benzoato‐κ2O,O′)[(E)‐2‐({[2‐(diethylamino)ethyl]imino}methyl)phenolato‐κ3N,N′,O]copper(II) dihydrate, [Cu(C7H5O2)(C13H19N2O)]·2H2O, 1 , [(E)‐2‐({[2‐(diethylamino)ethyl]imino}methyl)phenolato‐κ3N,N′,O](2‐phenylacetato‐κ2O,O′)copper(II), [Cu(C8H7O2)(C13H19N2O)], 2 , and bis[μ‐(E)‐2‐({[3‐(diethylamino)propyl]imino}methyl)phenolato]‐κ4N,N′,O:O;κ4O:N,N′,O‐(μ‐2‐methylbenzoato‐κ2O:O′)copper(II) perchlorate, [Cu2(C8H7O2)(C12H17N2O)2]ClO4, 3 , have been reported and all have been tested for their activity in the oxidation of d ‐galactose. The results suggest that, unlike the enzyme galactose oxidase, due to the precipitation of Cu2O, this reaction is not catalytic as would have been expected. The structures of 1 and 2 are monomeric, while 3 consists of a dimeric cation and a perchlorate anion [which is disordered over two orientations, with occupancies of 0.64 (4) and 0.36 (4)]. In all three structures, the central Cu atom is five‐coordinated in a distorted square‐pyramidal arrangment (τ parameter of 0.0932 for 1 , 0.0888 for 2 , and 0.142 and 0.248 for the two Cu centers in 3 ). In each species, the environment about the Cu atom is such that the vacant sixth position is open, with very little steric crowding. 相似文献