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1.
Alkynyl ketones are useful precursors and intermediates in synthetic organic chemistry1 and has evoked considerable interest. A number of methods for the synthesis of conjugated acetylenic ketones involve the reaction a metal acetylide with an acyl chlorides or another carboxylic acid derivative have been developed 2. Recently, the synthesis of α, β-conjugated acetylenic ketones catalyzed by Pd(Ⅱ) or by copper(Ⅰ)pd(Ⅱ) reaction of 1-alkynes and acyl chlorides have been described. The acylation of terminal alkynes by acyl chlorides in the presence of catalytic amounts copper(Ⅰ) salts leading to α, β-conjugated acetylenic ketones has also been reported. However, many of these reactions suffer from lack of high pressure (17 atm), long reaction time (30 h)and require low temperatures (-78℃). Our work involves the synthesis of conjugated acetylenic ketones via the reaction of terminal alkynes with aroyl chlorides in the presence of cuprous iodide under microwave irradiation conditions.  相似文献   

2.
The coordination polymerization of benzotriazole with metallic copper has been investigated by infrared and X-ray photoelectron spectroscopies. We found that benzotriazole could react with copper (0) under mild conditions to form bis (benzotriazolato) copper (Ⅱ) and benzotriazolato copper (Ⅰ)which covered the surface of copper metal in the shape of polymeric materials. Since benzotriazole is of great interest as a ligand in that its presence in many biological system with metal ions, and is considered as a corrosion inhibitor, this work will be in favour of the study of protective corrosion.  相似文献   

3.
Monitoring mitochondrial derived copper(Ⅱ) in live cells is highly demanded, but accurately detecting is unmet due to the interference with cytoplasmic copper(Ⅱ). Herein, we have reported the design,synthesis and characterization of photocontrollable fluorogenic probe, M_(Cu)~(-3), which is equipped with a photo-labile group(nitrobenzyl group) and mitochondria targeting unit(triphenylphosphonium salt).This novel probe showed an intense fluorescence enhancement in response to copper(Ⅱ) without interference from other metal cations in the biological condition(p H 6–9). The detection limit is 1.7 ×10~(-7) mol/L in HEPES buffer. The confocal fluorescence imaging results demonstrated M_(Cu)~(-3) can visualize mitochondrial copper(Ⅱ) in live mammalian cells. The clear advantage of our photocontrollable method is successful to avoid the influence of cytoplasmic copper(Ⅱ) during mitochondria specific detection.  相似文献   

4.
The effect of changing the amount of externally added cobalt(Ⅱ) serine, an organic metal compound, and the pH value of the enzyme solution on the interaction of copper zinc superoxide dismutase (Cu 2Zn 2SOD) with cobalt(Ⅱ) serine was studied by means of visible spectroscopy, inductively coupled plasma atomic emission spectrometry and measurement of enzyme activity. It was found that in aqueous solution, there exists a direct interaction of the metal ions of the active center in Cu 2Zn 2SOD with cobalt(Ⅱ) serine. As a result, part of the metal ions in the metalloenzyme were replaced by Co ion to form Co(Ⅱ) substituted derivatives of SOD and the catalytic activity of the enzyme decreased.  相似文献   

5.
ESR and IR measurements have been carried out for a copper(Ⅱ)complex ofphenolic polymeric crown ether,As a result,the triplet ESR spectrum(S=1)of 3d_z2ground state copper(Ⅱ)ions was first observed for the powder sample.It indicatedthat there existed intramolecular spin-spin interaction betweeen 3d_Z2 groundstate copper(Ⅱ)and copper(Ⅱ)ions.In this binuclear triplet cluster,the axialligntion of one water molecule in a sandwich position to two adjacent copper(Ⅱ)ions was also confirmed by IR spectra,All things considered,a possible structurefor the complex was proposed.  相似文献   

6.
By incorporating copper sulfate(CuSO_4)particles into acrylonitrile butadiene rubber(NBR)followed by heat pressing,a novel vulcanization method is developed in rubber through the formation of coordination crosslinking.This method totally differs from traditional covalent or non-covalent vulcanization approaches of rubber.No other vulcanizing agent or additional additive is involved in this process.By analyzing the results of DMA,XPS and FT-IR,it is found that the crosslinking of CuSO_4 particles filled NBR was induced by in situ coordination between nitrogen atoms of nitrile groups (-CN)and copper ions(Cu~(2 ))from CuSO_4.SEM and EDX results revealed the generation of a core(CuSO_4 solid particle)- shell(adherent NBR)structure,which leads to a result that the crosslinked rubber has excellent mechanical properties. Moreover,poly(vinyl chloride)(PVC)and liquid acrylonitrile-butadiene rubber(LNBR)were used as mobilizer to improve the coordination crosslinking of CuSO_4/NBR.The addition of PVC or LNBR could lead to higher crosslink density and better mechanical properties of coordination vulcanization.In addition,crystal water in CuSO_4 played a positive role to coordination crosslinking of rubber because it decreased the metal point of CuSO_4 and promoted the metal ionization.  相似文献   

7.
Two new binuclear copper(Ⅱ) complexes, [Cu(oxpn)CuL](ClO_4)_2, have been synthesizedand characterized, where oxpn is N,N' bis(3-aminopropyl)oxamido and L is 1,10-phenan-throline (phen) or 5-nitro-1,10-phenanthroline (NO_2-phen). The crystal structure and vari-able-temperature magnetic susceptibility (4- 300 K) of the Complex (L=phen) have beendetermined. Crystal data: orthorhombic system, space group Pnma, with a = 10.433(1), b11.458(2), c = 21.999(2)A, z = 4. Every copper(Ⅱ) ion is in a square pyramidal environment.The two copper(Ⅱ) ions are linked by μ-oxamido bridge and the separation of them is 5.208A. The singlet-triplet energy gap J was found equal to -452.92cm~(-1), indicating that astrongantiferromagnetic spin-exchange interaction operates between the copper(Ⅱ) ions.  相似文献   

8.
The recent revival of Li metal anodes(LMA) leads to a renewed interest in LMA as the ultimate choice for rechargeable lithium batteries towards high energy density. However, multiple challenges stand in the way of using LMA, of which high reactivity,dendrite growth, the difficulty of fabricating Li thin foils, and the flammability of organic liquid electrolytes are typical. Here, a writable Li metal ink(LMI) prepared by introducing biomass-derived carbon particles into molten Li is presented. Due to the significantly decreased surface tension, LMI is able to directly write on copper foils or other substrates that ultrathin Li foils with a remarkably small thickness(10 μm) can be achieved. The versatility of LMI is further demonstrated in addressing the interface issue between LMA and garnet-type solid-state electrolytes, where directly writing LMI on the garnet offers a perfect contact and enables an extremely low interfacial resistance of 6 Ω cm~2, in sharp contrast to 939 Ω cm~2 between the pure Li and the garnet. Due to the successful partnership with non-flammable solid-state electrolytes, ink-based technology may have a chance to bring us very close to the use of solid-state lithium metal batteries(SSLMBs) with high safety and high energy density.  相似文献   

9.
INTRODUCTION Schiff-base complexes are some of the most important stereochemical models in transition metal coordination chemistry, with their ease of preparation and structural variation.[1~4] Metal derivatives of Schiff-base have been studied extensively, and copper(II) and nickel (II) complexes play major roles in both synthetic and structural research. The geometry of the coordination sphere is usually planar in the case of Ni, but of Cu, a tetrahedral distortion is often observed.[…  相似文献   

10.
Heterometallic copper(Ⅱ)-lanthanide(Ⅲ) complexes have been made with a variety of exclusively O-donor ligands including betaines (zwitterionic carboxylates) and chloroac-etate,which are dinuclear CuLn,tetranuclear Cu2Ln2,pen-tanuclear Cu2Ln2,and octadecanuclear Cu12Ln6 complexes.Hie results show that subtle changes in both the carboxylates and acidity of the reaction solution can cause drastic changes in the structures of the products.Magnetic studies exhibit that shielding of the Ln3 4f electrons by the outer shell electrons is very effective to preclude significant coupling interaction between the Ln3 4f electrons and Cu2 3d electrons in either a mono-atomic hydroxide-bridged,or a carboxylate-bridged system.  相似文献   

11.
IntroductionOwing to the high thermal stability,low waterabsorption and excellent optical properties as wellas the utility in an elastomeric material forvibration and sound damping or in a soakingmaterial for oil spills[1— 4 ] ,the homopolymers andthe copolymers of norbornene have attracted aconsiderable attention.So far,a large number oftransition- metal compounds have been known tocatalyze the ring- opening olefin metathesispolymerization (ROMP) ,or the vinyl additionpolymerization (VAP) …  相似文献   

12.
Using metal ions to control the self-assembly of metallosupramolecules of varying architecture is one of the fascinating developments in supramolecular chemistry[1,2],particularly those concerned with the deliberate construction of molecular aggregates,like helices,rotaxanes,catenanes,knots,cages[3~6] and the crystal engineering of two or three dimensional networks with varied topology and interpenetration[7~10].Coordination bonds have proved themselves to be one of the most useful connectors in supramolecular self-assembly due to their versatile geometrical modes(e.g.linear,trigonal,square plane,tetrahedral,octahedral) in bond formations.By careful design of tailored ligands,various novel supramolecular architectures have been constructed.Recently,angular bi- or tridentate and other polydentate ligands have aroused a special interest,and a variety of molecular squares,boxes and cages[1~14] with internal cavity or void have been reported,in which many nanoscale structures are formed[6,15,16].We have been interested in the construction of metal based supramolecular structures with polydentate ligands[17~20] and herein report a new metallomacrocyclic complex assembled from two linear polydentate ligands and silver(Ⅰ) nitrate.  相似文献   

13.
1INTRODUCTION In recent years,dicarboxylic acids have been wide-ly used as poly-dentate ligands involved in various metal chelation reactions to form transition or rare earth metal complexes with interesting properties in material science[1~3]and biological systems[4~7].For example,Kim,Y.and his coworkers focus on the syn-theses of copper(II)complexes containing ligands of malonate and pyrazine to study their electronic con-ductivity and magnetic property[8].The importance of Tr(II)/dic…  相似文献   

14.
1 INTRODUCTION A variety of transition metal complexes with barbiturates have been prepared owing to their important roles in clinical detection and identi- fication of drug[1~5]. They have the general formula of M(Ⅱ)(barb)2L2, where M is a transition metal (Co, Cr, Zn, Cu etc), barb the anion of a substituted barbituratic acid and L an organic base, usually pyridine. In these complexes, the donor atom in the barbiturate anion is a deprotonated nitrogen atom and, the coordination …  相似文献   

15.
The authors presented a simple colorimetric assay for the detection of toxic heavy metal lead(Ⅱ) ion(Pb2+).Pentapeptide,cysteine-alanine-leacine-asparagine-asparagine(CALNN),functionalized gold nanoparticles(GNPs) were aggregated in the presence of the divalent metal ion in solution by an ion-templated chelation process,which caused an easily measurable change in the absorption spectrum of the particles.Typically,mono-dispersing GNPs exhibit an absorption band at 522 nm,corresponding to a red color solution,while aggregated GNPs have it at longer wavelengths,corresponding to a purple or blue color solution.The chelation/aggregation process is reversible via the addition of a strong metal ion chelator such as EDTA.Highly selective and sensitive detection of Pb2+ in aqueous solution is thus provided.A detection limit of 0.1 μmol/L of Pb2+ was demonstrated.  相似文献   

16.
A novel silica-supported resin with a cyclic monoamide of polymerized 4-acryloylmorpholine(Silica-AM) was synthesized, and adsorptivity to metal ions of major fission products(FP) was examined in HNO3 and HCl solutions. Silica-AM has a carbonyl oxygen atom outside of the 6-membered morpholine ring, and a cyclic structure that is different than other cyclic monoamide resins we have studied. These include polyvinylpolypyrrolidone(PVPP) and poly-N-vinyl-ε-caprolactam(VEC), both of which have coordinative carbonyl groups included in the ring. Silica-AM was similar to a cyclic monoamide we have reported because it exhibited adsorption to Pd(Ⅱ) and Re(VⅡ) in HNO3 of a particularly low concentration range. Silica-AM has an ether oxygen atom included in the ring as well. Considering the difference in the chemical structures of Silica-AM and other cyclic monoamide resins, it was suggested that oxygen atoms in the carbonyl group and in ether may be main contributors to Silica-AM's respective adsorptions to Pd(Ⅱ) and Re(VⅡ), and Mo(VI) and Zr(IV). Our results imply that the contribution of the two types of oxygen atoms to adsorption is more observable in an HCl system. The contribution of the ether oxygen atom to the adsorption of Pd(Ⅱ) was also suggested from our study on crystal prepared from 4-acetylmorpholine and palladium nitrate.  相似文献   

17.
Several PVP-stabilized colloidal platinum metals nanoparticles have been synthesized and characterized by FTIR and TEM.Comparing with the pure PVP,carbonyl groups of PVP in the mixture of PVP and the metal precursors or in the PVP-stabilized metal nanoparticles have obvious peak shifts in FTIR spectra.The peak shifts reveal the interaction between PVP and the metal species.The interaction between PVP and metal precursors has effect on the formation of the colloidal metal nanoparticles.Strength of the int...  相似文献   

18.
The high toxicity of many transition and post-transition metal ions, especially Hg2+ and Pb2 + , is well recognized and a lot of attention has been paid to control contamination of water supplies by toxic metal ions and to monitor the level of these metal ions in the environment. For the application purpose in controlling and monitoring the concentrations of specific metal ions in a complex matrix continuously and remotely by using ion-selective sensory devices, chemical sensors based on the synthetic fluoroionophores and chromoionophores capable of signaling complexation of metal ions have been reported, [1~ 5], and a series of dithidiaza 21-rown-7 bearing appended coumarin or 1-aminonaphthene as sidearms was synthesized. [6]  相似文献   

19.
A copper(Ⅱ) complex 1 of a novel macrocyclic polyamine ligand with hydroxylethyl pendant groups, 4,11-bis(hydroxylethyl)-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (L) has been synthesized and characterized. Rate enhancement for hydrolysis of p-nitrophenyl picolinate (PNPP) catalyzed by 1 was studied kinetically under Brij35 micellar condition. For comparision, the catalytic activity of corresponding copper(Ⅱ) complex 2 of non-substituted macrocyclic polyamine ligand, 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraaza-cyclotetradecane (L') toward the hydrolysis of PNPP was also investigated. The results indicate that the macrocyclic polyamine copper(Ⅱ) complex 1 effectively catalyzed the hydrolysis of PNPP, and the pendant ligand hydroxyl group or deprotonated pendant ligand hydroxyl group can act as catalytically active species in the reaction. A ternary Complex kinetic model involving metal ion, ligand and substrate has been proposed, and the results confirmed the reasonability of such kinetic model.  相似文献   

20.
1 INTRODUCTION During the past years, dicarboxylic acids have been widely used as one polydentate ligand invo- lved in various metal chelation reactions to form transition or rare earth metal complexes with inter- esting properties in material science[1] and biological systems[2]. For example, Kim Y and his coworkers focused on the synthesis of copper(II) complexes containing malonate and pyrazine ligands to study their magnetic property and electronic conducti- vity[3]. The importance o…  相似文献   

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