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1.
Malgorzata A. Kaczorowska Helen J. Cooper 《Journal of the American Society for Mass Spectrometry》2009,20(4):674-681
The electron capture dissociation (ECD) and collision-induced dissociation (CID) of complexes of polyamidoamine (PAMAM) dendrimers
with metal ions Ag+, Cu2+, Zn2+, Fe2+, and Fe3+ were determined by Fourier transform ion cyclotron resonance mass spectrometry. Complexes were of the form [PD + M + mH]5+ where PD = generation two PAMAM dendrimer with amidoethanol surface groups, M = metal ion, m = 2−4. Complementary information
regarding the site and coordination chemistry of the metal ions can be obtained from the two techniques. The results suggest
that complexes of Fe3+ and Cu2+ are coordinated via both core tertiary amines, whereas coordination of Ag+ involves a single core tertiary amine. The Zn2+ and Fe2+ complexes do not appear to involve coordination by the dendrimer core. 相似文献
2.
Formation of a Dimer of Trinuclear Helicates which Encapsulates an Array of Six Hydrogen‐Bonded Anions 下载免费PDF全文
Robert A. Faulkner Dr. Lindsay P. Harding Joshua Higginson Prof. Craig R. Rice Christopher Slater 《Angewandte Chemie (International ed. in English)》2014,53(49):13540-13543
The amine‐containing ligand L, composed of two bidentate pyridyl‐thiazole moieties linked by a 1,3‐diaminophenylene unit, reacts with copper(II) ions to form a dinuclear double helicate [Cu2L2]4+. Reaction of [Cu2L2]4+ with dihydrogen phosphate (0.5 equivalents) gives the unsaturated dinuclear double helicate [Cu2L2(OPO3H2)]3+. [Cu2L2(OPO3H2)]3+ further reacts with another 0.5 equivalents of dihydrogen phosphate to give a trinuclear circular helicate which then self‐assembles into a hexameric cluster [{Cu3L3(OPO3H2)3}]26+. 相似文献
3.
Zirah S Afonso C Linne U Knappe TA Marahiel MA Rebuffat S Tabet JC 《Journal of the American Society for Mass Spectrometry》2011,22(3):467-479
Lasso peptides constitute a class of bioactive peptides sharing a knotted structure where the C-terminal tail of the peptide is threaded through and trapped within an N-terminal macrolactam ring. The structural characterization of lasso structures and differentiation from their unthreaded
topoisomers is not trivial and generally requires the use of complementary biochemical and spectroscopic methods. Here we
investigated two antimicrobial peptides belonging to the class II lasso peptide family and their corresponding unthreaded
topoisomers: microcin J25 (MccJ25), which is known to yield two-peptide product ions specific of the lasso structure under
collision-induced dissociation (CID), and capistruin, for which CID does not permit to unambiguously assign the lasso structure.
The two pairs of topoisomers were analyzed by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry
(ESI-FTICR MS) upon CID, infrared multiple photon dissociation (IRMPD), and electron capture dissociation (ECD). CID and ECD
spectra clearly permitted to differentiate MccJ25 from its non-lasso topoisomer MccJ25-Icm, while for capistruin, only ECD
was informative and showed different extent of hydrogen migration (formation of c•/z from c/z•) for the threaded and unthreaded topoisomers. The ECD spectra of the triply-charged MccJ25 and MccJ25-lcm showed a series
of radical b-type product ions ( b¢n · ) \left( {b{\prime}_n^{ \bullet }} \right) . We proposed that these ions are specific of cyclic-branched peptides and result from a dual c/z• and y/b dissociation, in
the ring and in the tail, respectively. This work shows the potentiality of ECD for structural characterization of peptide
topoisomers, as well as the effect of conformation on hydrogen migration subsequent to electron capture. 相似文献
4.
Matthias Ziehe Tom N. Grossmann Oliver Seitz Michael W. Linscheid 《Rapid communications in mass spectrometry : RCM》2009,23(8):1132-1138
The use of peptide nucleic acids (PNAs) is steadily increasing in biochemistry and diagnostics. So far, PNAs have mostly been investigated using cationic conditions in mass spectrometry. Furthermore, the use of fragmentation techniques developed for peptides and proteins like infrared multiphoton dissociation (IRMPD) and electron capture dissociation (ECD) has barely been examined. However, especially the fragmentation behavior of PNA oligomers in negative ion mode is of high importance, due to the ability to interact with nucleic acids which are almost exclusively analyzed in the negatively charged state. In the current study PNA fragmentations under cationic and anionic conditions were investigated and different fragmentation techniques like collision‐induced dissociation (CID), IRMPD and ECD were applied. Especially when using CID and IRMPD, amide bonds were broken, whereas ECD resulted in the elimination of nucleobases. Differences were also observed between positive and negative ionization, while the sequence coverage for the negative ions was superior to positive ions. The fragmentation behavior using IRMPD led to almost complete sequence coverage. Additionally, in anions the interesting effect of multiple eliminations of HNCO was found. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
5.
Shawna M. Hengel Scott A. Shaffer Brook L. Nunn David R. Goodlett 《Journal of the American Society for Mass Spectrometry》2009,20(3):477-483
Bacterial adenosine diphosphate-ribosyltransferases (ADPRTs) are toxins that play a significant role in pathogenicity by inactivating
host proteins through covalent addition of ADP-ribose. In this study we used ADP-ribosylated Kemptide (LRRASLG) as a standard
to examine the effectiveness of three common tandem mass spectrometry fragmentation methods for assignment of amino acid sequence
and site of modification. Fragmentation mechanisms investigated include low-energy collision-induced dissociation (CID), infrared
multiphoton dissociation (IRMPD), and electron-capture dissociation (ECD); all were performed on a hybrid linear ion trap
Fourier transform ion cyclotron resonance mass spectrometer. We show that ECD, but neither CID nor IRMPD, of ADP-ribosylated
Kemptide produces tandem mass spectra that are interpretable with regard to amino acid sequence assignment and site of modification.
Examination of CID and IRMPD tandem mass spectra of ADP-ribosylated Kemptide revealed that fragmentation was primarily focused
to the ADP-ribose region, generating several potential diagnostic ions for use in discovery of ADP-ribosylated proteins. Because
of the lower relative sensitivity of ECD during data-dependent acquisition to CID, we suggest a 2-fold strategy where CID
and IRMPD are first used to detect ADP-ribosylated peptides, followed by sequence assignment and location of modification
by ECD analysis. 相似文献
6.
Myles W. Gardner Na Li Andrew D. Ellington Jennifer S. Brodbelt 《Journal of the American Society for Mass Spectrometry》2010,21(4):580-591
Infrared multiphoton dissociation (IRMPD) on a linear ion trap mass spectrometer is applied for the sequencing of small interfering
RNA (siRNA). Both single-strand siRNAs and duplex siRNA were characterized by IRMPD, and the results were compared with that
obtained by traditional ion trap-based collision induced dissociation (CID). The single-strand siRNA anions were observed
to dissociate via cleavage of the 5′ P—O bonds yielding c- and y-type product ions as well as undergo neutral base loss. Full
sequence coverage of the siRNA anions was obtained by both IRMPD and CID. While the CID mass spectra were dominated by base
loss ions, accounting for ∼25% to 40% of the product ion current, these ions were eliminated through secondary dissociation
by increasing the irradiation time in the IRMPD mass spectra to produce higher abundances of informative sequence ions. With
longer irradiation times, however, internal ions corresponding to cleavage of two 5′ P—O bonds began to populate the product
ion mass spectra as well as higher abundances of [a − Base] and w-type ions. IRMPD of siRNA cations predominantly produced
c- and y-type ions with minimal contributions of [a − Base] and w-type ions to the product ion current; the presence of only
two complementary series of product ions in the IRMPD mass spectra simplified spectral interpretation. In addition, IRMPD
produced high abundances of protonated nucleobases, [G + H]+, [A + H]+, and [C + H]+, which were not detected in the CID mass spectra due to the low-mass cut-off associated with conventional CID in ion traps.
CID and IRMPD using short irradiation times of duplex siRNA resulted in strand separation, similar to the dissociation trends
observed for duplex DNA. With longer irradiation times, however, the individual single-strands underwent secondary dissociation
to yield informative sequence ions not obtained by CID. 相似文献
7.
Terazzi E Guénée L Varin J Bocquet B Lemonnier JF Emery D Mareda J Piguet C 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(1):184-195
The axial connection of flexible thioalkyls chains of variable length (n=1–12) within the segmental bis‐tridentate 2‐benzimidazole‐8‐hydroxyquinoline ligands [ L12 Cn?2 H]2? provides amphiphilic receptors designed for the synthesis of neutral dinuclear lanthanides helicates. However, the stoichiometric mixing of metals and ligands in basic media only yields intricate mixtures of poorly soluble aggregates. The addition of AgI in solution restores classical helicate architectures for n=3, with the quantitative formation of the discrete D3‐symmetrical [Ln2Ag2( L12 C3?2 H)3]2+ complexes at millimolar concentration (Ln=La, Eu, Lu). The X‐ray crystal structure supports the formation of [La2Ag2( L12 C3?2 H)3][OTf]2, which exists in the solid state as infinite linear polymers bridged by S‐Ag‐S bonds. In contrast, molecular dynamics (MD) simulations in the gas phase and in solution confirm the experimental diffusion measurements, which imply the formation of discrete molecular entities in these media, in which the sulfur atoms of each lipophilic ligand are rapidly exchanged within the AgI coordination sphere. Turned as a predictive tool, MD suggests that this AgI templating effect is efficient only for n=1–3, while for n>3 very loose interactions occur between AgI and the thioalkyl residues. The subsequent experimental demonstration that only 25 % of the total ligand speciation contributes to the formation of [Ln2Ag2( L12 C12?2 H)3]2+ in solution puts the bases for a rational approach for the design of amphiphilic helical complexes with predetermined molecular interfaces. 相似文献
8.
Franoise Arnaud-Neu Maria Sanchez Marie-Jos Schwing-Weill 《Helvetica chimica acta》1985,68(4):840-845
Nature and Stability of Some Metallic Complexes of Dinucleating Cryptands in Solution III. The Monocycle [22]-Py2N4 The nature and stability of complexes formed by a new 22-membered monocycle L = [22]-Py2N4 with the cations Mn+ = Cu2+, Co2+, Ni2+, Zn2+, Cd2+, Pb2+, and Ag+ have been determined in aqueous solutions (0.01M NaClO4, 25°) by pH-metry and also, for the copper system, by UV-absorption spectrophotometry. The stepwise protonation constants of the four amine functions of L were 9.1, 8.3, 7.1 and 3.7 logarithms units, respectively. No evidence was found for the protonation of the two pyridine nitrogen atoms. Mononuclear complexes MLn+ were identified in all systems investigated, but the dinuclear species M2L2n+ were only found with Cu2+ and Ag+. The logarithms of the overall stability constants for the copper and silver complexes are CuL2+, 12.9; Cu2L4+, 18.6; Agl+, 6.3; Ag2L2+, 10.9, respectively. Mononuclear hydroxy species MLOH(n?1)+ were identified in all systems except those of copper and silver. No dinuclear hydroxy complexes were detected. The complexing properties of L are compared to those of the large and less rigid bis-dien. 相似文献
9.
Andrew W. Jones Peter J. Winn Helen J. Cooper 《Journal of the American Society for Mass Spectrometry》2012,23(12):2063-2074
The radical ion chemistry of a suite of S-nitrosopeptides has been investigated. Doubly and triply-protonated ions of peptides NYCGLPGEYWLGNDK, NYCGLPGEYWLGNDR, NYCGLPGERWLGNDR, NACGAPGEKWAGNDK, NYCGLPGEKYLGNDK, NYGLPGCEKWYGNDK and NYGLPGEKWYGCNDK were subjected to electron capture dissociation (ECD), and collision-induced dissociation (CID). The peptide sequences were selected such that the effect of the site of S-nitrosylation, the nature and position of the basic amino acid residues, and the nature of the other amino acid side chains, could be interrogated. The ECD mass spectra were dominated by a peak corresponding to loss of ?NO from the charge-reduced precursor, which can be explained by a modified Utah-Washington mechanism. Some backbone fragmentation in which the nitrosyl modification was preserved was also observed in the ECD of some peptides. Molecular dynamics simulations of peptide ion structure suggest that the ECD behavior was dependent on the surface accessibility of the protonated residue. CID of the S-nitrosylated peptides resulted in homolysis of the S?CN bond to form a long-lived radical with loss of ?NO. The radical peptide ions were isolated and subjected to ECD and CID. ECD of the radical peptide ions provided an interesting comparison to ECD of the unmodified peptides. The dominant process was electron capture without further dissociation (ECnoD). CID of the radical peptide ions resulted in cysteine, leucine, and asparagine side chain losses, and radical-induced backbone fragmentation at tryptophan, tyrosine, and asparagine residues, in addition to charge-directed backbone fragmentation. 相似文献
10.
Wen Zhou Kristina Håkansson 《Journal of the American Society for Mass Spectrometry》2013,24(11):1798-1806
Sulfated N-glycans released from bovine thyroid stimulating hormone (bTSH) were ionized with the divalent metal cations Ca2+, Mg2+, and Co by electrospray ionization (ESI). These metal-adducted species were subjected to infrared multiphoton dissociation (IRMPD) and electron capture dissociation (ECD) and the corresponding fragmentation patterns were compared. IRMPD generated extensive glycosidic and cross-ring cleavages, but most product ions suffered from sulfonate loss. Internal fragments were also observed, which complicated the spectra. ECD provided complementary structural information compared with IRMPD, and all observed product ions retained the sulfonate group, allowing sulfonate localization. To our knowledge, this work represents the first application of ECD towards metal-adducted sulfated N-glycans released from a glycoprotein. Due to the ability of IRMPD and ECD to provide complementary structural information, the combination of the two strategies is a promising and valuable tool for glycan structural characterization. The influence of different metal ions was also examined. Calcium adducts appeared to be the most promising species because of high sensitivity and ability to provide extensive structural information. Figure
? 相似文献
11.
Protonation of a Biologically Relevant CuII μ‐Thiolate Complex: Ligand Dissociation or Formation of a Protonated CuI Disulfide Species? 下载免费PDF全文
Erica C. M. Ording‐Wenker Martijn van der Plas Dr. Maxime A. Siegler Dr. Célia Fonseca Guerra Prof. Dr. Elisabeth Bouwman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(51):16913-16921
The proton‐induced electron‐transfer reaction of a CuII μ‐thiolate complex to a CuI‐containing species has been investigated, both experimentally and computationally. The CuII μ‐thiolate complex [CuII2( LMeS )2]2+ is isolated with the new pyridyl‐containing ligand LMeSSLMe , which can form both CuII thiolate and CuI disulfide complexes, depending on the solvent. Both the CuII and the CuI complexes show reactivity upon addition of protons. The multivalent tetranuclear complex [CuI2CuII2( LS )2(CH3CN)6]4+ crystallizes after addition of two equivalents of strong acid to a solution containing the μ‐thiolate complex [CuII2( LS )2]2+ and is further analyzed in solution. This study shows that, upon addition of protons to the CuII thiolate compound, the ligand dissociates from the copper centers, in contrast to an earlier report describing redox isomerization to a CuI disulfide species that is protonated at the pyridyl moieties. Computational studies of the protonated CuII μ‐thiolate and CuI disulfide species with LSSL show that already upon addition of two equivalents of protons, ligand dissociation forming [CuI(CH3CN)4]+ and protonated ligand is energetically favored over conversion to a protonated CuI disulfide complex. 相似文献
12.
Wolfgang Zarges Jonathan Hall Jean-Marie Lehn Carsten Bolm 《Helvetica chimica acta》1991,74(8):1843-1852
The chiral tris, and pentakis(bipyridine) ligand strands 3a and 4 were synthesised, each in optically pure form with (S,S)-configuration. Ligand 3a yielded substituted double-helical metal complexes, derived from the parent trihelicate structure 2 , with CuI and AgI ions. The spectral data, in particular the 1H-NMR spectra and the large positive Cotton effect, indicate that helicate formation occurs with very high induction of helicity. Together with consideration of the steric effects in the two possible helical diastereoisomers (P)- 1 and (M)- 1 that may be formed, the data favour the preferential generation of the right-handed double helicate (P)- 1 from the tris(bipyridine) strand 3a of(S,S)-configuration. 相似文献
13.
Voislav Blagojevic Sopeia N. Samad Laura Banu Michael C. Thomas Stephen J. Blanksby Diethard K. Bohme 《International journal of mass spectrometry》2011,299(2-3):125-130
Results of mass spectrometric studies are reported for the collisional dissociation of Group XI (Cu, Ag, Au) metal ion complexes with fatty acids (palmitic, oleic, linoleic and α-linolenic) and glycerolipids. Remarkably, the formation of M2H+ ions (M = Cu, Ag) is observed as a dissociation product of the ion complexes containing more than one metal cation and only if the lipid in the complex contains a double bond. Ag2H+ is formed as the main dissociation channel for all three of the fatty acids containing double bonds that were investigated while Cu2H+ is formed with one of the fatty acids and, although abundant, is not the dominant dissociation channel. Also, Cu(I) and Ag(I) ion complexes were observed with glycerolipids (including triacylglycerols and glycerophospholipids) containing either saturated or unsaturated fatty acid substituents. Interestingly, Ag2H+ ion is formed in a major fragmentation channel with the lipids that are able to form the complex with two metal cations (triacylglycerols and glycerophosphoglycerols), while lipids containing a fixed positive charge (glycerophospocholines) complex only with a single metal cation. The formation of Ag2H+ ion is a significant dissociation channel from the complex ion [Ag2(L–H)]+ where L = Glycerophospholipid (GP) (18:1/18:1). Cu(I) also forms complexes of two metal cations with glycerophospholipids but these do not produce Cu2H+ upon dissociation. Rather organic fragments, not containing Cu(I), are formed, perhaps due to different interactions of these metal cations with lipids resulting from the much smaller ionic radius of Cu(I) compared to Ag(I). 相似文献
14.
Ruthenium‐Containing Linear Helicates and Mesocates with Tuneable p53‐Selective Cytotoxicity in Colorectal Cancer Cells 下载免费PDF全文
Dr. Simon J. Allison Dr. David Cooke Francesca S. Davidson Prof. Paul I. P. Elliott Dr. Robert A. Faulkner Hollie B. S. Griffiths Owen J. Harper Omar Hussain Prof. P. Jane Owen‐Lynch Prof. Roger M. Phillips Prof. Craig R. Rice Samantha L. Shepherd Dr. Richard T. Wheelhouse 《Angewandte Chemie (International ed. in English)》2018,57(31):9799-9804
The ligands L1 and L2 both form separable dinuclear double‐stranded helicate and mesocate complexes with RuII. In contrast to clinically approved platinates, the helicate isomer of [Ru2( L1 )2]4+ was preferentially cytotoxic to isogenic cells (HCT116 p53?/?), which lack the critical tumour suppressor gene. The mesocate isomer shows the reverse selectivity, with the achiral isomer being preferentially cytotoxic towards HCT116 p53+/+. Other structurally similar RuII‐containing dinuclear complexes showed very little cytotoxic activity. This study demonstrates that alterations in ligand or isomer can have profound effects on cytotoxicity towards cancer cells of different p53 status and suggests that selectivity can be “tuned” to either genotype. In the search for compounds that can target difficult‐to‐treat tumours that lack the p53 tumour suppressor gene, [Ru2( L1 )2]4+ is a promising compound for further development. 相似文献
15.
Dr. Edmundo G. Percástegui Carlos Reyes‐Mata Dr. Marcos Flores‐Alamo Dr. Beatriz Quiroz‐García Prof. Ernesto Rivera Prof. Ivan Castillo 《化学:亚洲杂志》2018,13(5):520-527
Self‐assembly of bis‐picolyl‐appended calix[4]arene ( L ) with CuI or CuII salts resulted in a collection of multinuclear architectures capable of expressing structural reconfigurations in response to various chemical stimuli: addition of copper salt, solvents, or oxidation. Coordination of L to CuX (X=Br, I) selectively yielded dinuclear macrocycles CuI 2 L2Br2 ( 1 ) and CuI 2 L2I2 ( 3 ) that were transformed into tetranuclear assemblies CuI 4 L2Br4 ( 2 ) and CuI 4 L2I4 ( 4 ) upon further addition of CuX. These supramolecules persist as robust and discrete entities in solution that display red emission; notably, 4 exhibits luminescence thermochromism. Assembly of L with CuCl2 produced macrocycle CuII 2 L2Cl4 ( 5 ), which crystallised as cage [CuII 2 L4(μ‐Cl)]3+ ( 6 ) in the presence of MeOH. Two chemical signals—introduction of CuCl2 and addition of CH3CN—regenerated macrocycle 5 . Coordination of L to Cu(OTf) yielded macrocycle CuI 2 L2(OTf)2 ( 7 ) that also crystallised as cage 6 upon oxidation in CHCl3. 相似文献
16.
Dr. Dmitry B. Eremin Daniil A. Boiko Dr. Alexander Yu. Kostyukovich Dr. Julia V. Burykina Ekaterina A. Denisova Mariarosa Anania Dr. Jonathan Martens Dr. Giel Berden Prof. Dr. Jos Oomens Prof. Dr. Jana Roithová Prof. Dr. Valentine P. Ananikov 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(67):15672-15681
The product of a revealed transformation—NHC-ethynyl coupling—was observed as a catalyst transformation pathway in the Sonogashira cross-coupling, catalyzed by Pd/NHC complexes. The 2-ethynylated azolium salt was isolated in individual form and fully characterized, including X-ray analysis. A number of possible intermediates of this transformation with common formulae (NHC)nPd(C2Ph) (n=1,2) were observed and subjected to collision-induced dissociation (CID) and infrared multiphoton dissociation (IRMPD) experiments to elucidate their structure. Measured bond dissociation energies (BDEs) and IRMPD spectra were in an excellent agreement with quantum calculations for coupling product π-complexes with Pd0. Molecular dynamics simulations confirmed the observed multiple CID fragmentation pathways. An unconventional methodology to study catalyst evolution suggests the reported transformation to be considered in the development of new catalytic systems for alkyne functionalization reactions. 相似文献
17.
Dr. Yuya Domoto Masahiro Abe Dr. Takashi Kikuchi Prof. Dr. Makoto Fujita 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(9):3478-3482
The self-assembly of nanostructures is dominated by a limited number of strong coordination elements. Herein, we show that metal–acetylene π-coordination of a tripodal ligand (L) with acetylene spacers gave an M3L2 double-propeller motif (M=CuI or AgI), which dimerized into an M6L4 interlocked cage (M=CuI). Higher (M3L2)n oligomers were also selectively obtained: an M12L8 truncated tetrahedron (M=CuI) and an M18L12 truncated trigonal prism (M=AgI), both of which contain the same double-propeller motif. The higher oligomers exhibit multiply entangled facial structures that are classified as a trefoil knot and a Solomon link. The inner cavities of the structures encapsulate counteranions, revealing a potential new strategy towards the synthesis of functional hollow structures that is powered by molecular entanglements. 相似文献
18.
Two mononuclear and one dinuclear copper(II) complexes, containing neutral tetradentate NSSN type ligands, of formulation [CuII(L1)Cl]ClO4 (1), [CuII(L2)Cl]ClO4 (2) and [CuII2(L3)2Cl2](ClO4)2 (3) were synthesized and isolated in pure form [where L1 = 1,2-bis(2-pyridylmethylthio)ethane, L2 = 1,3-bis(2-pyridylmethylthio)propane and L3 = 1,4-bis(2-pyridylmethylthio)butane]. All these green colored copper(II) complexes were characterized by physicochemical and spectroscopic methods. The dinuclear copper(II) complex 3 changed to a colorless dinuclear copper(I) species of formula [CuI2(L3)2](ClO4)2,0.5H2O (4) in dimethylformamide even in the presence of air at ambient temperature, while complexes 1 and 2 showed no change under similar conditions. The solid-state structures of complexes 1, 2 and 4 were established by X-ray crystallography. The geometry about the copper in complexes 1 and 2 is trigonal bipyramidal whereas the coordination environment about the copper(I) in dinuclear complex 4 is distorted tetrahedral. 相似文献
19.
Two macrocyclic dinuclear complexes, [Cu2L1](PF6)2 and [Cu2L2](ClO4)2, were synthesized by cyclo-condensation between N,N′-bis(3-formyl-5-methylsalicylidene)ethylenediimine or N,N′- bis(3-formyl-5-n-butylsalicylidene)ethylenediimine and ethylenediamine in the presence of Cu2+ ions. The crystal structures of the complexes were studied. The variable-temperature magnetic susceptibilities and cyclic
voltammograms of the complexes were measured. The magnetic and electrochemical properties of the complexes were discussed.
The results show that the complexes display very strong antiferromagnetic exchanges and that all copper(II) complexes undergo
a one-electron transfer process. 相似文献
20.
A series of silver(I) supramolecular complexes, namely, {[Ag(L24)](NO3)}n ( 1 ), [Ag2(L24)(NO2)2]n ( 2 ), and {[Ag1.25(L24)(DMF)](PF6)1.25}n ( 3 ) were prepared by the reactions of 1‐(2‐pyridyl)‐2‐(4‐pyridyl)‐1,2,4‐triazole (L24) and silver(I) salts with different anions (AgNO3, AgNO2, AgPF6). Single‐crystal X‐ray diffraction indicates that 1 – 3 display diverse supramolecular networks. The structure of dinuclear complex 1 is composed of a six‐membered Ag2N4 ring with the Ag ··· Ag distance of 4.4137(3) Å. In complex 2 , the adjacent AgI centers are interlinked by L24 ligands into a 1D chain, the adjacent of which are further extended by the bridged nitrites to construct a 2D coordination architecture. Complex 3 shows a 3D (3,4)‐connected framework, which is generated by the linkage of L24 ligands. All complexes were characterized by IR spectra, elemental analysis, and powder X‐ray diffraction. Notably, a structural comparison of the complexes demonstrates that their structures are predominated by the nature of anions. Additionally, 1 and 2 show efficient dichromate (Cr2O72–) capture in water system, which can be ascribed to the anion‐exchange. 相似文献