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1.
Copper(I) complexes of the formula [Cu(L)(PPh3)2]X (1–4) (X = Cl(1), ClO4(2), BF4(3) and PF6(4)) [where L = N-(2-{[(2E)-2-(4-nitrobenzylidenyl)hydrazinyl]carbonyl}phenyl)benzamide; PPh3 = triphenylphosphine] have been prepared by the condensation of N-[2-(hydrazinocarbonyl)phenyl]benzamide with 4-nitrobenzaldehyde followed by the reaction with CuCl, [Cu(MeCN)4]ClO4, [Cu(MeCN)4]BF4 and [Cu(MeCN)4]PF6 in presence of triphenylphosphine as a coligand. Complexes 1–4 were then characterized by elemental analyses, FTIR, UV-visible and 1H NMR spectroscopy. Mononuclear copper(I) complexes 1–4 were formed with L in its keto form by involvement of azomethine nitrogen and the carbonyl oxygen along with two PPh3 groups. A single crystal X-ray diffraction study of the representative complex [(Cu(L)(PPh3)2]CIO4 (2) reveals a distorted tetrahedral geometry around Cu(I). Crystal data of (2): space group = C2/c, a = 42.8596 (9) Å, b = 14.6207 (3) Å, c = 36.4643 (7) Å, V = 20,653.7 (7) Å3, Z = 16. Complexes 1–4 exhibit quasireversible redox behaviour corresponding to a Cu(I)/Cu(II) couple. All complexes show blue-green emission as a result of fluorescence from an intra-ligand charge transition (ILCT), ligand to ligand charge transfer transition (LLCT) or mixture of both. Significant increase in size of the counter anion shows marked effect on quantum efficiency and lifetime of the complexes in solution. 相似文献
2.
Qiufei Hou 《Journal of luminescence》2007,126(2):447-451
Schiff bases N,N′-o-phenylenebis (salicylideneimine) (H2L1), N,N′-p-phenylenebis (salicylideneimine) (H2L2) and their corresponding boron complexes (BF2)2L1, (BF2)2L2 were synthesized, respectively. The two boron complexes have been characterized by 1H NMR, mass spectrometry and elemental analysis, while the luminescent properties of them were investigated with UV-VIS spectroscopy and photoluminescence spectroscopy. Then the three-layer devices [ITO/NPB (60 nm)/(BF2)2L1 (50 nm)/Alq3 (20 nm)/LiF (1 nm)/Al (200 nm)] (device I) and [ITO/NPB (60 nm)/(BF2)2L2 (50 nm)/Alq3 (20 nm)/LiF (1 nm)/Al (200 nm)] (device II) were fabricated by vacuum deposition. These two devices both exhibited blue green emission at 500 nm, but showed different luminances and efficiencies. 相似文献
3.
Some nickel(II) and zinc(II) complexes of the type [Ni(L)(phen/bipy)]X (1a–6a) and [Zn(L) (phen/bipy)]X (1b–6b) (where L = 2-{(E)-[(4-trimethylsilylethynylphenyl)imino]methyl}-4-(4-nitro phenylethynyl)phenol; phen = 1, 10-phenanthroline, bipy = 2, 2´-bipyridine; X = ClO4 ?, BF4 ?, PF6 ?) have been prepared and characterized on the basis of elemental analyses, FTIR, 1H NMR and mass spectral studies. The molecular structure of L was determined by single crystal X-ray diffraction studies. The electrochemical behaviour of the Ni(II) complexes indicate that the phen complexes appears at more positive potential as compared to those for bipy complexes, as a consequence of its strong π-acidic character. TGA was carried out to study the thermal behavior of the complexes. Room temperature luminescence is observed for all complexes corresponds to π → π* ILCT transition. The size of the counter anion and heterocyclic coligands phen and bipy shows marked effect on emission properties of the complexes. 相似文献
4.
A new fluorescent probe based on a bis-benzimidazole diamide N 2,N 2′-bis[(1-ethyl-benzimidazol-2-yl)methyl]biphenyl-2,2′-dicarboxamide ligand L 1 with a biphenyl spacer group and a Copper(II) trinuclear metallacycle has been synthesized and characterized by X-ray single crystallography, elemental and spectral (FT-IR, 1H & 13C NMR, UV-Visible) analysis. The fluorescence spectra of L 1 in MeOH show an emission band centered at 300 nm. This band arises due to benzimidazolyl moiety in the ligating system. The diamide L 1 in the presence of Cu2+ show the simultaneous ‘quenching’ of (300 nm) and ‘enhancement’ of (375 nm) emission band. Similar fluorescence behavior was found in water–methanol mixture (9:1). The new emission band at 375 nm is attributed to intra ligand π–π* transition of the biphenyl moiety. L 1 exhibited high selectivity and sensitivity towards Cu2+ in both the medium over other common metal ions like Ni2+, Co2+, Mn2+, Mg2+, Zn2+, Pb2+ and Hg2+. The binding constant with Cu2+ was calculated by the Benesi-Hildebrand equation. Selective “off-on-off” behavior of L 1 in methanol has also been studied. The fluorescent intensity of 375 nm bands in L 1 enhances (turns-on) upon addition of Cu2+ and quenches (turn-off) upon addition of Na2-EDTA. 相似文献
5.
Blue light-emitting spiro[benzotetraphene-fluorene] (SBTF)-based host materials, 3-(1-naphthyl)-10-naphthylspiro[benzo[ij]tetraphene-7,9′-fluorene] (1), 3-(2-naphthyl)-10-naphthylspiro[benzo[ij]tetraphene-7,9′-fluorene] (2), and 3-[2-(6-phenyl)naphthyl]-10-naphthylspiro[benzo[ij]tetraphene-7,9′-fluorene] (3) were designed and prepared via multi-step Suzuki coupling reactions. Introducing various aromatic groups into SBTF core lead to a reduction in band gap and a determination of the color purity and luminescence efficiency. Typical sky-blue fluorescent organic light emitting diodes with the configuration of ITO/N,N′-di(1-naphthyl)-N,N′-bis[(4-diphenylamino)phenyl]-biphenyl-4,4′-diamie (60 nm)/N,N,N′,N′-tetra(1-biphenyl)-biphenyl-4,4′-diamine (30 nm)/host: dopant (30 nm, 5 %)/LG201 (electron transporting layer, 20 nm)/LiF/Al were developed using SBTF derivatives as a host material and p-bis(p-N,N-diphenyl-aminostyryl)benzene (DSA-Ph) as a sky-blue dopant material. A device obtained from three materials doped with DSA-Ph showed color purity of 0.148 and 0.239, a luminance efficiency of 7.91 cd/A, and an external quantum efficiency >4.75 % at 5 V. 相似文献
6.
A Cu(I) complex, [Cu(Dppp)(DPEphos)]BF4 (Dppp=2,3-diphenyl-pyrazino[2,3-f][1,10]phenanthroline, DPEphos=Bis[2-(diphenylphosphino)phenyl]ether), is synthesized and used as the dopant in bright electrophosphorescent devices with the general structure ITO/m-MTDATA (30 nm)/NPB (20 nm)/CBP: ×wt% [Cu(Dppp)(DPEphos)]BF4 (30 nm)/Bphen (20 nm)/Alq3 (20 nm)/LiF (0.8 nm)/ Al (200 nm). These devices exhibit a maximum brightness of 4483 cd/m2 and a peak efficiency of 3.4 cd/A. Compared with previously reported similar devices based on Cu(I) complexes, the brightness of the devices presented in this article is the best. Meanwhile, 2% [Cu(Dppp)(DPEphos)]BF4-based devices exhibit white light-emitting properties with CIE coordinates of (0.32. 0.35) at 10 V. 相似文献
7.
Mehmet Gulcan Ümit Doğru Gülsiye Öztürk Abdulkadir Levent Esvet Akbaş 《Journal of fluorescence》2014,24(2):389-396
A series of Schiff bases (L 1 , L 2 and L 3 ) were prepared by refluxing aromatic aldehydes with N-Aminopyrimidine derivatives in methanol and ethanol. The structures of synthesized compounds were characterized by FTIR, 1H NMR, 13C NMR and microanalysis. The electrochemical behaviors of the Schiff base ligands were also discussed. Moreover, the evaluation of absorption and emission properties of the structures were carried out in five different solvents. The products show visible absorption maxima in the range of 304–576 nm, and emission maxima from 636 to 736 nm in all solvents tested. 相似文献
8.
In this work, the dipod 9,10-bis(8-quinolinoxymethyl)anthracene (1) and for comparison, monopod 9-(8-quinolinoxymethyl)anthracene (2) have been synthesized. The fluoroionophore 1 in pH 7.1 HEPES buffered CH3CN:H2O (4:1 v/v) solution shows quenching only with Cu2+ with lowest limit of detection 150 nM, amongst various metal ions. Fluoroionophore 1 could also be applied to sense Co2+ with lowest limit of detection 600 nM. By modulating the pH of the solution and concentration of Cu2+, 1 shows respective “On-Off-On” and “On-Off” fluorescent switching. The self-assembly of two Cu2+ ions and two molecules of fluoroionophore 1 to form closed structure [Cu2(L)2]4+ seems to be responsible for nanomolar sensitivity towards Cu2+. The combination of delayed second protonation of 1 (pKa2?=?2.6) and stepwise protonation of [Cu2 L 2]4+ causes unusual stability of [Cu(LH)2]4+ even at pH?<?2. Figure
The fluoroionophore 1 shows quenching only with Cu2+ with lowest limit of detection 150 nM. The combination of delayed second protonation of 1 (pKa2?=?2.6) and stepwise protonation of [Cu2 L 2]4+ causes unusual stability of [Cu(LH)2]4+ even at pH?<?2. 相似文献
9.
Anil D. Naik Antoine P. Railliet Marinela M. D?rtu Yann Garcia 《Hyperfine Interactions》2012,204(1-3):119-123
With a new bis-azole molecular fragment (Htt) bearing 1,2,4-triazole and tetrazole, a mononuclear complex [Fe(tt)2(H2O)4]·2H2O (1), a trinuclear complex [Fe3(tt)6(H2O)6]·2H2O (2) and a 1D coordination polymer [Fe(tt)(Htt)2]BF4·2CH3OH (3) were obtained by varying reaction conditions. Htt acts either as an anionic or neutral ligand depending upon the reaction medium and pH. Thermal variation of spin states of 1–3 were investigated in the range 77–300?K by 57Fe M?ssbauer spectroscopy. 1 totally remains in high-spin state over the entire temperature range whereas no spin crossover was evidenced in 2. Nearly 1:1 high-spin and low-spin population ratio is found in 3, which remains constant over the entire temperature range investigated. 相似文献
10.
Three novel Cu(I) complexes, [CuDPEphos(NN)]BF4, where NN=1-(4-5′-phenyl-1,3,4-oxadiazolylbenzyl)-2-pyridinylbenzoimidazole (OXD-Pybm; L1) (1), 1-(4-carbazolylbutyl)-2-pyridinylbenzimidazole (Carl-Pybm; L2) (2), and 1-H-2-pyridinylbenzimidazole (HPybm; L3) (3), were synthesized. The photoluminescent (PL) properties of 1-3 and the electroluminescent (EL) properties of complexes 1 and 2 were systematically studied. The maximum brightness of 2-based devices was 8669 cd/m2, which should be the best among the reported Cu(I) complexes-based devices. 相似文献
11.
Yu-Xiu Liu Peng-Xiang Zhang Yong-Qiang Li Hai-Bin Song Qing-Min Wang 《Molecular diversity》2014,18(3):593-598
Based on structures of insecticidal chlorfenapyr and antibiotic natural pyrrolomycins, a series of new 2-benzylpyrroles and 2-benzoylpyrroles (with or without ethoxymethyl group on the nitrogen of pyrrole) were designed and synthesized. These compounds or their parent compounds possess weak acidity and high lipophilicity, the two characteristic properties for uncouplers of oxidative phosphorylation; therefore, they are expected to have insecticidal and acaricidal activity. The bioassay result verified that both 2-benzylpyrroles 17 and 2-benzoylpyrroles 19 had varied degrees of insecticidal activity against oriental armyworm depending on the substituents on the benzene ring, but they did not give any acaricidal activity. Conversely, most N-alkylated compounds 18 and 20 exhibited both insecticidal activity and acaricidal activity, of which compound 18i [4-bromo-2-(2,4-dichlorobenzyl)-1-(ethoxymethyl) -5-(trifluoromethyl) - 1 \(H\) -pyrrole-3-carbonitrile] has IC \(_{50}\) as low as 10–20 mg L \(^{-1}\) on both activities. 相似文献
12.
A novel compound 1 containing rhodamine B and macrocyclic groups has been synthesized. It was found to exhibit a reversible colorimetric response, high selectivity and sensitivity for Cu(II) ion over other commonly coexistent metal ions. The colorimetric and fluorescent response to Cu(II) can be conveniently detected even by the naked eye, which provided a facile method for visual detection of Cu(II). Approximate 71 and 53-fold enhancement in the absorbance at about 557 nm and fluorescence intensity at about 580 nm were estimated when Cu(II) ion was added to the aqueous media of compound 1. The detection limit was calculated to be 2 μM. 相似文献
13.
Three anthracen- or pyrene-based coumarin derivatives have been successfully synthesized and characterized by EA, IR and 1H NMR. The photophysical properties of all derivatives were investigated by UV-Vis and photoluminescence spectroscopic analysis. Their thermal stabilities were demonstrated by TGA. These compounds exhibit strong blue mission under ultraviolet light excitation and have potential possible to explore organic electroluminescent materials. The vacuum-processed doped devices with a configuration of ITO/TAPC (20 nm)/TBADN: b1 (x wt%, 30 nm)/TPBi (50 nm)/Liq (2 nm)/Al (150 nm) was fabricated, in which the devices based on b1 exhibited the best electroluminescence performance with a maximum brightness of 8165 cd/m2 and a maximum luminous efficiencies of 6.13 cd/A and a maximum external quantum efficiency (EQE) of 2.75%. 相似文献
14.
Murugesan Sankarganesh Jeyaraj Dhaveethu Raja Paul Raj Adwin Jose Gujuluva Gangatharan Vinoth Kumar Jegathalaprathaban Rajesh Ramalingam Rajasekaran 《Journal of fluorescence》2018,28(4):975-985
Biochemically active Cu(II) and Zn(II) complexes [CuL(ClO4)2(1) and ZnL(ClO4)2(2)] have been synthesized from N,N donor Schiff base ligand L derived from4,6-dichloropyrimdine-5-carboxaldehyde with 4-(2-aminoethyl)morpholine. The L, complexes 1 and 2 have been structurally characterized by elemental analysis, 1H-NMR, FTIR, MS, UV-Visible and ESR techniques. The results obtained from the spectral studies supports the complexes 1 and 2 are coordinated with L through square planar geometry. DFT calculations results supports, the ligand to metal charge transfer mechanism can occur between L and metal(II) ions. The antimicrobial efficacy results have been recommended that, complexes 1 and 2 are good anti-pathogenic agents than ligand L. The interaction of complexes 1 and 2 with calf thymus (CT) DNA has been studied by electronic absorption, viscometric, fluorometric and cyclic voltammetric measurements. The calculated Kb values for L, complexes 1 and 2 found from absorption titrations was 4.45?×?104, L; 1.92?×?105, 1 and 1.65?×?105, 2. The Ksv values were found to be 3.0?×?103, 3.68?×?103and 3.52?×?103 for L, complexes 1 and 2 by using competitive binding with ethidium bromide (EB). These results suggest that, the compounds are interacted with DNA may be electrostatic binding. The molecular docking studies have been carried out to confirm the interaction of compounds with DNA. Consequently, in vitro anticancer activities of L, complexes 1 and 2 against selected cancer (lung cancer A549, liver cancer HepG2 and cervical carcinoma HeLa) and normal (NHDF) cell lines were assessed by MTT assay. 相似文献
15.
A series of pyrazoline derivatives containing pyrazole group were synthesized and characterized by means of 1H NMR, FT-IR, MS and elemental analysis, and their UV–vis absorption behavior and fluorescent properties were also measured. Moreover, the influence of metal ions on spectral properties of synthetic products was examined with compound A 5 as an example. It has been found that all synthetic pyrazoline derivatives show two remarkable absorption peaks at about 260 and 360 nm and the maximum emission peak at 445–467 nm. Especially, the joined of Co2+ can quench the fluorescence of compound A 5 obviously. 相似文献
16.
A series of ruthenium (III) complexes of the formulae [Ru(4-Mephtpy)2]Cl3(1) [Ru(L 1 )], [Ru(3,4,5-tmphtpy)2]Cl3(2) [Ru(L 2 )], and [Ru(4-thptpy)2]Cl3(3) [Ru(L 3 )], (where L?=?terpy?=?2.2′:6′2″ terpyridine ligands) are synthesized. The complexes were characterized by elemental analyses, spectroscopic and electrochemical data. The density functional theory (DFT) outlines the geometric optimisation and electronic charge transition of these complexes. Photophysical studies describe that the luminescence of Ru(III) complexes is due to electronic transition between the energy levels of singly unoccupied molecular orbitals (SUMO) and singly occupied molecular orbitals (SOMO). It also exhibits the potential charge transfer to π–π* and n–π* states due to MLCT and ILCT processes of the complexes. The observed bands centered at 591 and 620 nm demonstrate that these emissions originated from the transition of SUMO to SOMO energy levels, that is, from the radiative decay from the doublet exciton. Due to the heavy metal effect of Ru(III) ions the photophysical behaviour depends on the MLCT process. In conclusion, that the all three Ru(L 1 -L 3 ) complexes are fallen orange emission. 相似文献
17.
Gustav Berggren Ping Huang Lars Eriksson Magnus F. Anderlund 《Applied magnetic resonance》2009,36(1):9-24
A penta-coordinated Mn(II) compound [dqpMnCl2] (1) (dqp = 2,6-di-(8-quinoline-yl)-pyridine) has been synthesized and its X-ray crystallographic structure is reported here. Magnetic susceptibility measurements confirmed a high-spin Mn(II) (S = 5/2) center in 1. The X-band EPR spectrum of 1 in dimethylformamide solution exhibits widely distributed transitions in the spectral range from 0 to 700 mT with particularly well-resolved hyperfine lines due to the 55Mn (I = 5/2) nucleus. The abundance of highly resolved transition lines in the spectrum facilitated the electron paramagnetic resonance spectral simulation which revealed large zero-field splitting and g-anisotropies. When dissolved, 1 exists in equilibrium with a hexa-coordinated species, the latter probably resulting from disassociation of one chlorido-ligand allowing ligation of two solvent molecules. The redox behavior of 1 was studied and was compared to that of a structural analog for which water oxidation in the presence of a chemical oxidant has been shown. The results from water oxidation trials of 1 are discussed. 相似文献
18.
S. V. Litke T. V. Mezentseva A. S. Litke G. N. Lyalin A. Yu. Ershov 《Optics and Spectroscopy》2000,89(6):847-853
Luminescence of mixed ligand complexes of ruthenium(II) of the types cis-Ru(bpy)2X2(I), cis-[Ru(bpy)2(PPh3)X](BF4)(II), and cis-Ru(bpy)(PP)X2(III) (X = CN, NO2, PPh3 is triphenyl phosphine; PP is 1,2-bis(diphenylphospino)ethane (dppe) and cis-,2-bis(diphenylphosphino)ethylene (dppene)) is studied in alcohol matrices (EtOH/MeOH, 4:1) frozen at 77 K. A sequence of complexes I–III exhibits an additive (in the number of phosphorous atoms) blue shift of the absorption and luminescence bands and an increase in the quantum yield of luminescence and in the excited-state lifetime. The rate constant of nonradiative deactivation of the excited state decreases more than by an order of magnitude in the sequence I–III of cyano complexes and only by three times in a sequence of nitro complexes. This is assumed to be caused by a specific (in the hydrogen bond type) interaction of nitro groups of complexes with a proton solvent. 相似文献
19.
Yanxin Zhang Xiaohan Yu Hongqing He Jinglai Zhang Li Wang 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2014,68(2):1-12
Theoretical studies for a series of mono- and binuclear zinc (II) complexes Zn(CH3COO)2(H2L)2 [H2L = N-2-propenyl-N ′-2-pyridinylthiourea] (A), Zn2(CH3COO)2(H3L-a)2 [H3L-a = 2-[(2-hydroxy phenyl)methylene]hydrazine-N-phenylcarbothioamide] (B), and Zn(H3L-b)2 [H3L-b = 2-[(2-hydroxy phenyl)methylene]hydrazine-N-(2-propenyl)carbothioamide] (C) have been performed on their structures and excited-state absorption spectra. The singlet ground-state geometries are fully optimised at three DFT levels, i.e., B3LYP, B3PW91, and M06. Different geometries, i.e., strongly distorted tetrahedral coordination environment in complex A, distorted square-pyramidal environment in complex B, and irregular octahedral mode in complex C are identified. Consequently, the spectroscopic properties are calculated by means of time-dependent density functional theory (TDDFT) with the Polarisable Continuum Model (PCM) based on the optimised gas-phase geometries. Three absorption peaks are identified for every complex, which are in good agreement with the experimental ones. For complex A, all three absorption peaks centered at 280.33 nm, 268.09 nm, and 250.87 nm, respectively, are ascribed to the (p,π) → π* transition with a mixed intraligand charge-transfer (ILCT)/ligand-ligand charge-transfer (LLCT) character. The composition of frontier orbitals involved in major absorption bands for the three complexes shows similarities, which results in the almost homologous transition attributions and characteristics. A remarkable bathochromic shift in the lowest-lying absorption band is observed for complexes B and C as compared with complex A, which is attributed to the decreased H (HOMO)-L (LUMO) energy gap (ΔE |HOMO-LUMO|) by the formation of conjugate metallocycles in complexes B and C. 相似文献
20.
Puhui Xie Fengqi Guo Sen Yang Denghui Yao Guoyu Yang Lixia Xie 《Journal of fluorescence》2014,24(2):473-480
A new NBD-rhodamine dye (1) was developed as a colorimetric and ratiometric fluorescent chemosensor for Hg2+ with good selectivity in aqueous ethanol solutions under neutral to basic conditions. Sensor 1 showed absorption at 468 nm and a weak emission at 529 nm (? F ?=?0.063) in ethanol/aqueous tris buffer (9:1, v/v) of pH 9.17 solution. Bathochromic shifts in both absorption (492 nm) and fluorescence spectra (569 nm, ? F ?=?0.129), respectively upon addition of 2 equiv. of Hg2+ were observed. The ring-opening reaction of the spirolactam form to the corresponding xanthene form was not found. The interaction of Hg2+ with chemosensor 1 resulted in the deprotonation of the secondary amine conjugated to the NBD component so that the electron-donating ability of the N atom was enhanced. Deprotonation-ICT mechanism of secondary amines was suggested for the ratiometric fluorescent chemosensing for Hg2+. 相似文献