首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Heteroleptic silver(I) nitrate complexes containing the bis[2-(diphenylphosphano)phenyl]ether (DPEphos) ligand and the heterocyclic thioamides pyridine-2(1H)-thione (py2SH), pyrimidine-2(1H)-thione (pymtH), 4,6-dimethylpyrimidine-2(1H)-thione (dmpymtH), 1,4,5,6-tetrahydropyrimidine-2-thione (thpymtH) or 1,3-imidazolidine-2-thione (imtH2) have been synthesized and characterized by IR and UV-Vis spectroscopy, elemental analyses and melting point determinations. The complexes can be obtained by the addition of the thioamide ligand to an AgNO3-diphosphane adduct in dichloromethane/ethanol solution. The molecular structure of [Ag(DPEphos)(py2SH)2]NO3 complex has been established by single-crystal X-ray diffraction. The structure features a tetrahedral silver(I) center with two phosphorus atoms from the chelating diphos ligand, and the exocyclic sulfur atom of two heterocyclic thioamide units. Intense blue-green emission is observed in the region 470-483 nm for all the complexes in the solid state and in solution at ambient temperature.  相似文献   

2.
Reactions of copper(I) halides with racemic 2,2′-bis(diphenylphosphano)-1,1′-binaphthyl (rac-binap) in 1:1 molar ratio afforded mononuclear complexes of the type [CuX(rac-binap)] (X = Cl, Br, I) which, on further treatment with 1 equiv. of pyridine-2-thione (py2SH), pyrimidine-2-thione (pymtH) or 4,6-dimethyl-pyrimidine-2-thione (dmpymtH) gave rise to the formation of mixed-ligand complexes of the formula [CuX(rac-binap)(thione)]. The molecular structures of [CuBr(rac-binap)(py2SH)] · 2CH2Cl2, [CuBr(rac-binap)(py2SH)] · CH2Cl2 and [CuBr(rac-binap)(dmpymtH)] · CH2Cl2 have been established by single-crystal X-ray diffraction. Each of the complexes features a distorted tetrahedral copper(I) center with the phosphane acting in a chelating fashion. The complexes are strongly luminescent in the solid state at ambient temperature. Unusually, the [CuBr(rac-binap)(py2SH)] · 2CH2Cl2 molecules crystallise in a chiral space group with independent S- and R-enantiomers in the asymmetric unit.  相似文献   

3.
Two new copper(I) halide complexes bearing 2-(2-benzimidazolyl)-6-methylpyridine(Hbmp) and PPh3 ligands, Cu(Hbmp)(PPh3)X(X = Br(1);I(2)),have been synthesized and characterized.Single-crystal X-ray structure analysis reveals that the halide ligand has a significant impact on the Cu-Npyridyl bond lengths.Complexes 1 and 2 show the solid-state emissions at ambient temperature,varying with the halide bound to the {Cu(Hbmp)(PPh3)} motif,which are perhaps best attributed to the metal-to-ligand charge-transfer(Cu(I)→Hbmp) transition mixed with some ligand-to-ligand charge-transfer(X and PPh3→Hbmp) character.  相似文献   

4.
The 1 : 1 molar-ratio reaction between copper(I) bromide and 4,5-bis(diphenylphosphano)-9,9-dimethyl-xanthene (xantphos) in acetonitrile results in the formation of [CuBr(xantphos)], which displays luminescent emission at room temperature. The molecular structure of the complex, established by single-crystal X-ray diffraction, features a trigonal planar geometry around the metal center, with the diphosphane acting as a chelate. The high rigidity and steric requirements of the xanthene unit rationalize the unusual coordination number of CuI.  相似文献   

5.
The reactions between five ferrocenyl derivatives containing both a CO and at least an imidazole or pyridine nitrogen atom and AgPF6, AgOTf, or [Cu(NCCH3)4]PF6 precursors were studied. The ligand {[bis(2-pyridyl)amino]carbonyl}ferrocene (L3), derived from (2-pyridyl)amine, favored tetrahedral coordination of Ag+ (with two ligands) and of Cu+ (with two acetonitrile ligands left from the precursor). In all the other ligands, both metal centers coordinated linearly to two ligands, preferring the imidazole or pyridinic nitrogen to other nitrogen atoms (amine) or oxygen donors.When the counter anions were triflate, the crystal structure showed a dimerization of the complex, with the ferrocenyl moieties occupying cis positions, by means of a weak Ag?Ag interaction. This was shown experimentally in the crystal structure of complex [Ag(L1)2]OTf (L1 = ferrocenyl imidazole) and in the presence of peaks corresponding to {Ag2(L2)3(OTf)}+ and {Ag2(L2)4(OTf)}+ in the mass spectra of [Ag(L2)2]OTf (L2 = ferrocenyl benzimidazole). In all complexes containing PF6, there was no evidence for dimerization. Indeed, in the crystal structure of [Ag(L2)2]PF6, the ferrocenyl moieties occupy trans positions and the metal centers are far from each other. DFT calculations showed that the energy of the cis and trans conformers is practically the same and the balance of crystal packing forces leads to dimerization when triflate is present.  相似文献   

6.
Reaction of copper(I) chloride with 1,3-imidazoline-2-thione (imzSH) in the presence of Ph3P in 1:2:2 or 1:1:2 (M:L:PPh3) molar ratios yielded a compound of unusual composition, [Cu2(imzSH)(PPh3)4Cl2] · CH3OH (1), whose X-ray crystallography has shown that its crystals consist of four coordinated [CuCl(1κS-imzSH)(PPh3)2] (1a), and three coordinated [Cu(PPh3)2Cl] (1b) independent molecules in the same unit cell. In contrast, crystals of complexes of copper(I) bromide/iodide are formed by single molecules of [CuBr(1κS-imzSH)(PPh3)2] · H2O (2) and [CuI(1κS-imzSH)(PPh3)2] (3), respectively, similar to molecule 1a. The related ligand, 1,3-benzimidazoline-2-thione (bzimSH) formed a complex [CuBr(1κS-bzimSH)(PPh3)2] · CH3COCH3 (4), similar to 2. The formation of 1a and 1b has been also revealed by NMR spectroscopy. The NMR spectra of 24 also showed weak signals indicating formation of compounds similar to 1b. It reveals that the lability of the Cu–S bond varies in the order: Cl ? Br ∼ I. Weak interactions {e.g. C–H?π electrons of ring, –NH?halogens/oxygen, C–H?halogens/oxygen, π?π (between rings)} have played an important role in building 2D chains of complexes 14.  相似文献   

7.
Some copper(I) complexes of the formula [Cu(L)(PPh3)2]X (1-4) [where L = 2-phenyl-3-(benzylamino)-1,2-dihydroquinazolin-4(3H)-one; PPh3 = triphenylphosphine; X = Cl, NO3, ClO4 and BF4] have been prepared and characterized on the basis of elemental analysis, IR, UV-Vis and 1H NMR spectral studies. The representative complex of the series 4 has been characterized by single crystal X-ray diffraction which reveal that in the complex the central copper(I) ion assumes the irregular distorted-tetrahedral geometry. Cyclic voltammetry of the complexes indicate a quasireversible redox behavior corresponding to Cu(II)/Cu(I) couple. All the complexes exhibit intraligand (π → π) fluorescence with high quantum yield in dichloromethane solution.  相似文献   

8.
Bis(diphenylphosphano)alkane- and 1-Diphenylphosphano-2-(2-pyridino)ethane-N-arylsulfinylamine Nickel(0) Complexes Synthesis and properties of the bis(diphenylphosphano)alkane-N-phenyl-sulfinylamine-nickel(0) complexes [Ni{Ph2P(CH2)nPPh2}(PhNSO)] (n = 2 dppe, n = 3 dppp, n = 4 dppb) as well as of the 1-(diphenylphosphano)-2-(2-pyridino)ethane nickel(0) complexes [Ni(dpppe)2], [Ni(dpppe)(p-TolNSO)] and [Ni(dpppe)(PPh3)2] are described. These compounds have been characterized by i. r. and 31P n.m.r. spectroscopy. The N-arylsulfinylamine ligands are η2-(N, S)-side on coordinated.  相似文献   

9.
Kurnia K  Giles DE  May PM  Singh P  Hefter GT 《Talanta》1996,43(12):2045-2051
The stability (formation) constants of the binary Cu(I)-CN complexes have been measured in five aqueous mixtures containing from 10% to 70% v/v acetonitrile (MeCN) by glass electrode potentiometry at 25 °C and an ionic strength of l M (NaClO4). The constants show monotonic increases with MeCN concentration, the changes being greatest for the higher order complexes, consistent with the unfavourable solvation of CN in these mixtures. The sparing solubility of CuCN(s) prevented determination of the stability constant for CuCN 0 (soln.) at low MeCN concentrations.  相似文献   

10.
6-Aminocoumarin reacts with pyridine-2-carboxaldehyde and has synthesized N-[(2-pyridyl)methyliden]-6-coumarin (L). The ligand, L, reacts with [Cu(MeCN)4]ClO4/AgNO3 to synthesize Cu(I) and Ag(I) complexes of formulae, [Cu(L)2]ClO4 and [Ag(L)2]NO3, respectively. While similar reaction in the presence of PPh3 has isolated [Cu(L)(PPh3)2]ClO4 and [Ag(L)(PPh3)2]NO3. All these compounds are characterized by FTIR, UV-Vis and 1H NMR spectroscopic data. In case of [Cu(L)(PPh3)2]ClO4 and [Ag(L)(PPh3)2]NO3, the structures have been confirmed by X-ray crystallography. The structure of the complexes are distorted tetrahedral in which L coordinates in a N,N′ bidentate fashion and other two coordination sites are occupied by PPh3. The ligand and the complexes are fluorescent and the fluorescence quantum yields of [Cu(L)(PPh3)2]ClO4 and [Ag(L)(PPh3)2]NO3 are higher than [Cu(L)2]ClO4 and [Ag(L)2]NO3. Cu(I) complexes show Cu(II)/Cu(I) quasireversible redox couple while Ag(I) complexes exhibit deposition of Ag(0) on the electrode surface during cyclic voltammetric experiments. gaussian 03 computations of representative complexes have been used to determine the composition and energy of molecular levels. An attempt has been made to explain solution spectra and redox properties of the complexes.  相似文献   

11.
Preparation and Structure of Tetraethylcyclotetraarsoxane Complexes of Copper(I) Halides The polymeric complexes [Cu4Cl4{cyclo-(C2H5AsO)4}3]n ( 1 ), [Cu3Br3{cyclo-(C2H5AsO)4}2]n ( 2 ) and [Cu6I6{cyclo-(C2H5AsO)4}3]n ( 3 ) were prepared by the reaction of (C2H5AsO)n and CuX (X = Cl, Br, I) in acetonitrile and characterised by X-ray analysis. All three complexes contain only tetramers (C2H5AsO)4 as ligands, in which the As4O4 ring systems coordinate between two and four Cu-atoms. In each case one As4O4 ring with a crown-shaped conformation is observed, which coordinates either four (in 1 ) or three (in 2 and 3 ) axially sited Cu-atoms. In addition there are further (C2H5AsO)4 ligands, which display either a boat-chair- (in 1 ) or a twist-chair-conformation (in 1–3 ). The individual building units are connected to one another via Cu? X? Cu bridges (in 2 and 3 ) and/or centrosymmetric As4O4 ring systems (in 1–3 ) into chain ( 1 ) or layer structures ( 2 und 3 ).  相似文献   

12.
An ion chromatographic (IC) method was developed for the determination of cyanate in gold cyanidation samples containing large concentrations of metallo-cyanide complexes. The analysis was performed on a Waters HC IC-Pak A anion-exchange column with an anthranilic acid eluent, with detection achieved using indirect UV at 355 nm. Two procedures were developed for removal of the metallo-cyanide complexes prior to the IC analysis. The first was a manual off-line method which used solid-phase extraction cartridges containing a strong anion-exchange resin to trap the complexes and to then enable determination of cyanate without interference. In the second approach, an automated on-line method was developed which used an anion-exchange guard column to trap the complexes and a column switching valve to allow backflushing of the cyanate from the guard column. This enabled the total analysis to be performed in a time of 10–14 min, depending on the sample composition. Finally, a comparison of results obtained by the standard Kjeldahl nitrogen method for cyanate and the IC method revealed an interference in the Kjeldahl method for samples containing large concentrations of Cu(I)-cyanide complexes.  相似文献   

13.
Four new ligands, (4-methyl-phenyl)-pyridin-2-ylmethylene-amine (A), (2,3-dimethyl-phenyl)-pyridin-2-ylmethylene-amine (B), (2,4-dimethyl-phenyl)-pyridin-2-ylmethylene-amine (C) and (2,5-dimethyl-phenyl)-pyridin-2-ylmethylene-amine (D), and their corresponding copper(I) complexes, [Cu(A)2]ClO4 (1a), [Cu(B)2]ClO4 (1b), [Cu(C)2]ClO4 (1c), [Cu(D)2]ClO4 (1d), [Cu(A)(PPh3)2]ClO4 (2a), [Cu(B)(PPh3)2]ClO4 (2b), [Cu(C)(PPh3)2]ClO4 (2c) and [Cu(D)(PPh3)2]ClO4 (2d), have been synthesized and characterized by CHN analyses, 1H and 13C NMR, IR and UV–Vis spectroscopy. The crystal structures of [Cu(B)2]ClO4 (1b), [Cu(C)2]ClO4 (1c) and [Cu(A)(PPh3)2]ClO4 · 1/2CH3CN (2a) were determined from single crystal X-ray diffraction. The coordination polyhedron about the copper(I) center in the three complexes is best described as a distorted tetrahedron. A quasireversible redox behavior is observed for the complexes.  相似文献   

14.
Copper(I) halide complexes having thermally activated delayed fluorescence (TADF) and phosphorescence have attracted much attention. Here, a series of four-coordinate dinuclear copper(I) halide complexes, [CuX(bpbp)]2 (bpbp = 2,2′-bis(diphenylphosphino)biphenyl, X = I (1), Br (2) and Cl (3)), were synthesized, and their molecular structures and photophysical properties were investigated. The structural analysis reveals that two copper(I) centers are bridged by two halogen ligands to form a dinuclear structure with a four-membered Cu2X2 ring. These complexes exhibit yellow to blue emission in the solid state at room temperature and have peak emission wavelengths at 575–487 nm with microsecond lifetimes (τ = 6.2–19.8 μs) and low emission quantum yields (<0.01%). The emissions of 13 originate from MLCT, XLCT, and IL (intraligand) transitions. Three complexes displayed good thermal stability.  相似文献   

15.
[Cu(SRaaiNR′)(PPh3)X] complexes are synthesized by the reaction of CuX (X = Cl, Br, I), triphenylphosphine and 1-alkyl-2-[(o-thioalkyl)phenylazo]imidazole (SRaaiNR′). The single crystal X-ray structure of [Cu(SEtaaiNH)(PPh3)I] (SEtaaiNH = 2-[(o-thioethyl)phenylazo]imidazole) shows a distorted tetrahedral geometry of the copper center with bidentate, N(azo), N(imidazole) chelation of SEtaaiNH and coordination from PPh3 and iodine. These complexes show a trans-to-cis isomerization upon irradiation with UV light. The reverse transformation, cis-to-trans isomerization, is very slow with visible light irradiation and is thermally accessible. The quantum yields (?t→c) of the trans-to-cis isomerization of [Cu(SRaaiNR′)(PPh3)X] are lower than the free ligand values. This is due to the increased mass and rotor volume of the complexes compared to the free ligand data. The rate of isomerization follows the order: [Cu(SRaaiNR′)(PPh3)Cl] < [Cu(SRaaiNR′)(PPh3)Br] < [Cu(SRaaiNR′)(PPh3)I]. The activation energy (Ea) of the cis-to-trans isomerization is calculated by a controlled temperature reaction. DFT computation of representative complexes has been used to determine the composition and energy of the molecular levels.  相似文献   

16.
以2-氯吡啶(1)、2-甲氨基乙醇(2)和4-氟苯甲醛(4)为主要原料,经2步反应合成了4-{2-[N-甲基-N-(2-吡啶基)氨基乙氧基]}苯甲醛(5).第1步反应n(2)∶n(1)=4∶1,反应温度160℃,反应时间约6h,采用减压蒸馏进行后处理,2-[N-甲基-N-(2-吡啶基)氨基]乙醇(3)的收率在93%以上,过量2的回收率在97%以上,回收的2可以重复使用.第2步反应用氢氧化钠做碱性试剂,用甲苯和水分别做为两相的溶剂,在相转移催化剂CTAB作用下进行,经优化后5的收率可达90%以上.2步反应总收率达83%以上.  相似文献   

17.
Abstract

Four new heteroleptic copper(I) complexes bearing either 2-pyridyl-1,2,3-triazole (pytri) or the related triphenylamine (TPA) substituted (TPA-tripy) ligands and the ancillary ligands 6,6′-dimesityl-2,2′-bipyridine (diMesbpy) or bis[(2-diphenylphosphino)phenyl] ether (POP) were synthesized in good yields (75-95%). All the complexes were extensively characterized using nuclear magnetic resonance (NMR) spectroscopies and electrospray ionization mass spectrometry (ESIMS) and in the case of the two pytri compounds the solid state structures were determined via X-ray crystallography. The pytri complexes showed MLCT absorption bands which shift from 433?nm for the diMesbpy complex to 347?nm for POP. TPA-pytri complexes introduce an ILCT band resulting in improved visible absorption (376?nm, 26,400 M?1 cm?1 for [Cu(TPA-pytri)(diMesbpy)](PF6)). Emission from this ILCT state (470?nm, Φ?=?0.08) was red-shifted compared to the free ligand with negligible effects from ancillary ligands. Band assignments were confirmed with resonance Raman spectroscopy and TD-DFT calculations.  相似文献   

18.
A one pot, multi-component CuAAC reaction has been developed for the generation of alkyl, benzyl or aryl substituted bi and tridentate pyridyl-1,2,3-triazole ligands from their corresponding halides, sodium azide and alkynes in excellent yields. The ligands have been fully characterized by elemental analysis, HR-ESMS, IR, 1H and 13C NMR and in the ferrocenyl substituted cases the structures were confirmed by X-ray crystallography. Additionally, we have examined the coordination chemistry of these ligands and found that a variety of geometrically diverse Cu(II) and Ag(I) complexes, including interesting tri and tetrasilver complexes, can be formed.  相似文献   

19.
Synthesis and Structure of the Copper Complex 2-(2-Hydroxy-5-methylphenyl)-6-(2-hydroxyphenyl)pyridinato(2?)dipyridin-copper(II) and of the free Ligand The tridentate diacidic ligand 2-(2-hydroxy-5-methyl)-6-phenyl-6-(2-hydroxyphenyl)pyridine 4a was synthesized and characterized by X-ray structural analysis. The compound forms a copper complex, 2-(2-Hydroxy-5-methyl-phenyl)-6-(2-hydroxyphenyl)pyridinato(2?)-dipyridine copper(II), which was crystallized from pyridine solution. The coordination number of the central atom copper ist five.  相似文献   

20.
The present work reports the synthesis and spectroscopic and electrochemical characterization of homoleptic copper(I) complexes with substituted pirazino [2,3-f]-1,10-phenanthroline, RpplR′, (R = H, Me, COOH or COOMe, and R′ = H, Me) as ligand. The ligand ppl works as an acceptor of electronic density, which is delocalized mainly in the quinoxaline part of its structure. The UV–Vis spectra show that all the complexes display bands in the range 400–650 nm, which are MLCT in character. The λmax and extinction coefficients of the MLCT band at 450 nm and the LC band do not change significatively when varying the R substituent. Nevertheless, the intensity of the shoulder around 500 nm does change; this absorption has been related to either a static or dynamic flattening distortion of the complex D2d → D2 symmetry. The cyclic voltammetry of the complexes shows irreversible redox processes with Ep values that do not follow the tendency expected from the donor/acceptor character of the substituents on the ligand. All the complexes studied showed no emission both in acetonitrile and dichloromethane as solvent at room temperature and under argon atmosphere.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号