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1.
Luminescent cuprous complexes are an important class of coordination compounds due to their relative abundance, low cost and ability to display excellent luminescence. The title ionic trinuclear Cu3I2 complex, tris[μ2‐diphenyl(pyridin‐2‐yl)phosphane‐κ2P:N]di‐μ3‐iodido‐tricopper(I)(3 CuCu) hexafluoridophosphate, [Cu3I2(C39H32NP)3]PF6, conventionally abbreviated as [Cu3I2(Ph2PPy)3]PF6, is described. Each CuI atom is coordinated by two μ3‐iodide ligands and by a P and an N atom from two Ph2PPy ligands, giving rise to a CuI2PN tetrahedral coordination geometry about each CuI centre. The electronic absorption and photoluminescence properties of this trinuclear cluster have been studied on as‐synthesized samples, which had been examined previously by powder X‐ray diffraction. A detailed time‐dependent density functional theory (TD–DFT) study was carried out and showed a green emission derived from a halide‐to‐ligand charge transfer and metal‐to‐ligand charge transfer 3(X+M)LCT excited state.  相似文献   

2.
Cu4P4X4Fe2 (X = Cl, Br) cages are formed upon reactions of octaethyl‐1,1′‐diphosphaferrocene (odpf) with the respective CuI halide in CH2Cl2/CH3CN solvent mixtures. These cages have adamantoid Cu4X4P2 cores with two planar anelated CuP2Fe rings as the flaps. Both complexes 1 and 2 feature tri‐ and tetracoordinate CuI ions and an additional acetonitrile solvent molecule in the crystal. In 1 , the solvent molecule is coordinated to one copper ion whereas it remains uncoordinated in 2 . The tricoordinate CuI ions show a slight pyramidalization at the metal atom and somewhat short contacts to the other tricoordinate CuI ion in 2 or the Cu3‐triangle in 1 . NMR spectroscopy revealed easy decoordination of the acetonitrile ligand from 1 and a dynamic “windshield‐wiper”‐type process that interconverts the differently coordinated phospholide rings of each odpf ligand and the tri‐ and tetracoordinate CuI ions.  相似文献   

3.
Cu(CF3COO)2 reacts with tert‐butylacetylene (tBuC≡CH) in methanol in the presence of metallic copper powder to give two air‐stable clusters, [CuI15(tBuC≡C)10(CF3COO)5]?tBuC≡CH ( 1 ) and [CuI16(tBuC≡C)12(CF3COO)4(CH3OH)2] ( 2 ). The assembly process involves in situ comproportionation reaction between Cu2+ and Cu0 and the formation of two different clusters is controlled by reactants concentration. The clusters consist of Cu15 and Cu16 cores co‐stabilized by strong by σ‐ and π‐bonded tert‐butylethynide and CF3COO? (together with methanol molecule in 2 ). Their stabilities in solution were confirmed using electrospray ionization mass spectrometry in which the cluster core remains intact for 1 in chloroform and acetone, and for 2 in acetonitrile. Strong thermochromic luminescence in the near infrared (NIR) region was observed in the solid‐state. Of particular interest, the emission maximum of 1 is red‐shifted from 710 nm at 298 K to 793 nm at 93 K, along with a 17‐fold fluorescence enhancement. In contrast, 2 exhibits red shift from 298 to 123 K followed by blue shift from 123 to 93 K. The emission wavelength was correlated with the structural parameters using variable‐temperature X‐ray single‐crystal analyses. The rich cuprophilic interaction plays a significant role in the formation of 3LMCT (tBuC≡C→Cux) excited state mixed with cluster‐centered (3CC) characters, which can be considerably influenced by temperature, leading to thermochromic luminescence. The present work provides 1) a new synthetic protocol for the high‐nuclear CuI–alkynyl clusters; 2) a comprehensive insight into the mechanism of thermochromic luminescence; 3) unusual emissive materials with the characters of NIR and thermochromic luminescence simultaneously.  相似文献   

4.
The metal–organic frameworks (MOF) of cluster [Cu4I4(DABCO)2] (DABCO=1,4‐diazabicyclo[2.2.2]octane) have been prepared and characterized as two different crystalline forms, I and II . Form I is obtained by reaction of DABCO and CuI in aqueous solution or by solvothermal reaction, while form II is obtained by reacting DABCO and CuI in acetonitrile. Their luminescence properties in the solid state have been analyzed at room temperature and at 77 K. MOF II has bright emission with a maximum at 556 nm that shifts bathochromically at low temperature in conjunction with a marked change in the colour of the emission. The emission of MOF I has a maximum at 580 nm and a less pronounced temperature dependence. The peculiar luminescence properties of the two isomers have been interpreted by utilising current knowledge on the excited states properties of CuI cubane clusters. The two isomers exhibit a high degree of porosity and can release the disordered solvent molecules trapped in the channels, whilst preserving the crystal structure. Isomer I can be converted into II on exposure to acetonitrile or methanol vapour, whereas II reverts to I when heated in a closed pan at 250 °C.  相似文献   

5.
Two binuclear heteroleptic CuI complexes, namely Cu−NIR1 and Cu−NIR2, bearing rigid chelating diphosphines and π-conjugated 2,5-di(pyridin-2-yl)thiazolo[5,4-d]thiazole as the bis-bidentate ligand are presented. The proposed dinuclearization strategy yields a large bathochromic shift of the emission when compared to the mononuclear counterparts (M1–M2) and enables shifting luminescence into the near-infrared (NIR) region in both solution and solid state, showing emission maximum at ca. 750 and 712 nm, respectively. The radiative process is assigned to an excited state with triplet metal-to-ligand charge transfer (3MLCT) character as demonstrated by in-depth photophysical and computational investigation. Noteworthy, X-ray analysis of the binuclear complexes unravels two interligand π–π-stacking interactions yielding a doubly locked structure that disfavours flattening of the tetrahedral coordination around the CuI centre in the excited state and maintain enhanced NIR luminescence. No such interaction is present in M1–M2. These findings prompt the successful use of Cu−NIR1 and Cu−NIR2 in NIR light-emitting electrochemical cells (LECs), which display electroluminescence maximum up to 756 nm and peak external quantum efficiency (EQE) of 0.43 %. Their suitability for the fabrication of white-emitting LECs is also demonstrated. To the best of our knowledge, these are the first examples of NIR electroluminescent devices based on earth-abundant CuI emitters.  相似文献   

6.
From a predesigned grid, [CuII5CuI4L6] ? (I)2 ? 13 H2O ( 1 ), in which LH2 was a pyrazinyl‐triazolyl‐2,6‐substituted pyridine, we successfully synthesized an extended 3D complex, 1[{CuII5CuI8L6}{μ‐[CuI3(CN)6]}2 ? 2 CH3‐ CN] ( 2 ), that displayed unprecedented coexistence of all the five known coordination geometries of copper. Grid 1 displayed monovalent central metal exchange (CME) of CuI for AgI for the first time, as well as the formation of tri‐iodide in the crystalline state. These systems were investigated for their magnetic properties. Remarkably, grid 1 showed much higher catalytic activity than the Ag‐exchanged product for synthesis of a substituted triazole, 1‐benzyl‐4‐phenyl‐1H‐1,2,3‐triazole.  相似文献   

7.
The supramolecular coordination polymers (SCP); 3[Cu (CN)2(Me3Sn)(pyz)], pyrazine-trimethyltin-bis (cyanide) copperI SCP 1 , [Cu2(CN)3(Ph3Sn)(pyz)], pyrazine-triphenyltin-tris (cyanide) dicopperI SCP 3 and [Cu2(CN)4(Ph3Sn)(Pyz2caH)2], bis-pyrazine-2-carboxylic acid- triphenyltin-tetrakis (cyanide) dicopperI SCP 4 and the coordination complex (CC), [CuII (Pyz2-ca)2(H2O)2]; diaquo-bis-(pyrazine-2-carboxylato) copper(II) complex: CC 2 , are synthesized by self-assembly method at ambient conditions. Single crystal X-ray structures of SCP 1 and CC 2 indicate the presence of CuI and CuII which adopt tetrahedral and octahedron geometry, respectively. The structures of SCP 3 and SCP 4 are solved by the density functional theory (DFT) calculations and spectroscopic methods. The Cu centers acquire triagonal plane, linear and tetrahedral geometry, respectively. The CN-R3Sn-NC spacer and pyrazine or pyrazine-2-carboxylic acid ligands extend the structures to 3D-network. The tested compounds 1–4 are designed and synthesized to examine their effects on viability and proliferation of five human cancer cell lines. Also, they are tested for antioxidant activity using ABTS assay and rate erythrocyte hemolysis.  相似文献   

8.
Rational regulation of electronic structures and functionalities of framework materials still remains challenging. Herein, reaction of 4,4′,4′′-nitrilo-tribenzhydrazide with tris(μ2-4-carboxaldehyde-pyrazolato-N,N′)-tricopper (Cu3Py3) generates the crystalline copper organic framework USTB-11(Cu). Post-modification with divalent nickel ions affords the heterometallic framework USTB-11(Cu,Ni). Powder X-ray diffraction and theoretical simulations reveal their two-dimensional hexagonal structure geometry. A series of advanced spectroscopic techniques disclose the mixed CuI/CuII state nature of Cu3Py3 in USTB-11(Cu,Ni) with a uniform bistable Cu34+(CuI2CuII) : Cu35+(CuICuII2) (ca. 1 : 3) oxidation state, resulting in a significantly improved formation efficiency of the charge-separation state. This endows the Ni sites with enhanced activity and USTB-11(Cu,Ni) with outstanding photocatalytic CO2 to CO performance with a conversion rate of 22 130 μmol g−1 h−1 and selectivity of 98 %.  相似文献   

9.
In a previous communication we reported the site-directed generation of a heterodinuclear FeIIICuII complex ( 1 ) by using an asymmetric dinucleating ligand FloH. The iron(III) ion was introduced first on the preferential metal-binding site of the ligand that led to the formation of the thermodynamically favored five-membered chelate ring upon metal-binding. Copper(II) was introduced in the next step. The stepwise metalation strategy reported previously has now been extended to synthesize a series of heterodinuclear FeIIIMII [M = Mn ( 2 ), Fe ( 3 ), Co ( 4 ), and Ni ( 5 )] and FeIICuI ( 1a ) as well as the homodinuclear CuICuI ( 6 ) complexes. The complexes were characterized by X-ray crystallography (except for 1a and 6 ), and by a limited number of spectroscopic methods. Complex 1 with a labile solvent binding site at FeIII reacted with H2O2 to form a transient intermediate that showed reactivity typical of metal peroxide complexes. The metal centers in the complexes 2 – 5 are coordinatively saturated, and hence they showed no reactivity with H2O2. Complex 1a reacted with O2 via an intermolecular pathway to form a μ-oxo bridged tetrameric complex 1b , which was structurally characterized. This is in contrast to the homodinuclear CuICuI and heme FeIICuI cores, which prefer an intramolecular pathway for O2 activation.  相似文献   

10.
A novel dinuclear Cu(II) complex [Cu2(C10H8NO2)4(CH3OH)2] · 2CH3OH (I), where C10H8NO2 is anion of 3-indolylacetic acid, was synthesized and characterized by elemental analysis, IR spectroscopy, 1H NMR and single crystal X-ray diffraction. X-ray crystallography shows that Cu2+ ion is six-coordinated, embedded in a distorted octahedral center. Each Cu2+ ion is coordinated with four carboxylic oxygen atoms from four ligands, one oxygen atom from methanol and the other Cu2+ ion. Each ligand links two Cu2+ ions through carboxylic oxygen atoms, forming a dinuclear Cu(II) complex. The complex forms a two-dimensional layer structure through N-H??Oi intermolecular hydrogen bonds. The interaction of complex I with calf-thymus DNA (CT-DNA) has been explored by electronic absorption spectroscopy, EB (ethidium bromide) displacement experiments, salt effect, and viscosity measurements. All the results indicate that the complex binds to DNA in a partial intercalative mode. Moreover, agarose gel electrophoresis assay demonstrates that the complex possesses the ability to cleave pBR322 plasmid DNA.  相似文献   

11.
Unprecedented stabilization of the copper(I ) oxidation state is demonstrated for the complex cation [Cu(bfp)2]+ ( 1 ) due to the steric and electronic effects of the CF3 groups (E1/2(CuII/CuI)=+1.55 V vs. SCE). The redox existence range of the copper(I ) species is remarkably high at 2.77 V. It is emissive in solution at room temperature and shows great potential as a photocatalyst; in the excited state it is a very potent photooxidant.  相似文献   

12.
To develop new and flexible CuI containing luminescent substances, we extend our previous investigations on two metal-centered species to four metal-centered complexes. These complexes could be a basis for designing new organic light-emitting diode (OLED) relevant species. Both the synthesis and in-depth spectroscopic analysis, combined with high-level theoretical calculations are presented on a series of tetranuclear CuI complexes with a halide containing Cu4X4 core (X=iodide, bromide or chloride) and two 2-(diphenylphosphino)pyridine bridging ligands with a methyl group in para (4-Me) or ortho (6-Me) position of the pyridine ring. The structure of the electronic ground state is characterized by X-ray diffraction, NMR, and IR spectroscopy with the support of theoretical calculations. In contrast to the para system, the complexes with ortho-substituted bridging ligands show a remarkable and reversible temperature-dependent dual phosphorescence. Here, we combine for the first time the luminescence thermochromism with time-resolved FTIR spectroscopy. Thus, we receive experimental data on the structures of the two triplet states involved in the luminescence thermochromism. The transient IR spectra of the underlying triplet metal/halide-to-ligand charge transfer (3M /XLCT) and cluster-centered (3CC) states were obtained and interpreted by comparison with calculated vibrational spectra. The systematic and significant dependence of the bridging halides was analyzed.  相似文献   

13.
Developing strong visible-light-absorbing (SVLA) earth-abundant photosensitizers (PSs) for significantly improving the utilization of solar energy is highly desirable, yet it remains a great challenge. Herein, we adopt a through-bond energy transfer (TBET) strategy by bridging boron dipyrromethene (Bodipy) and a CuI complex with an electronically conjugated bridge, resulting in the first SVLA CuI PSs ( Cu-2 and Cu-3 ). Cu-3 has an extremely high molar extinction coefficient of 162 260 m −1 cm−1 at 518 nm, over 62 times higher than that of traditional CuI PS ( Cu-1 ). The photooxidation activity of Cu-3 is much greater than that of Cu-1 and noble-metal PSs (Ru(bpy)32+ and Ir(ppy)3+) for both energy- and electron-transfer reactions. Femto- and nanosecond transient absorption and theoretical investigations demonstrate that a “ping-pong” energy-transfer process in Cu-3 involving a forward singlet TBET from Bodipy to the CuI complex and a backward triplet-triplet energy transfer greatly contribute to the long-lived and Bodipy-localized triplet excited state.  相似文献   

14.
Reactions of CuCl2 with different CN complexes in presence of a neutral ancillary ligand lead to two novel mixed-valence Cu complexes [CuII(bpy)CuI(CN)3]n, 1 (bpy = 2,2′-bipyridine) and {[CuII(tn)2][CuI4(CN)6]}n2 (tn = 1,3-diaminopropane). For compound 1, the asymmetric unit involves two Cu ions Cu1 and Cu2 (CuI and CuII centres, respectively) which strongly differ in their environments. The Cu1 ion presents a CuC4 pseudo-tetrahedral geometry, while the Cu2 ion presents a CuN5 slightly distorted square-pyramidal geometry. The extended structure of 1 is generated by three cyano ligands which differ in their coordination modes. One CN group has a μ3 coordination mode and bridges two CuI and one CuII ion, while the two other CN groups act as μ2 bridges leading to a sophisticated 3-D structure. As for 1, the asymmetric unit of 2 involves three crystallographically different Cu ions (Cu1A and Cu1B, presumably CuI centres, and Cu2 presumably CuII centres). The Cu2 ion presents centrosymmetric CuN4 coordination environments involving four nitrogen atoms from two bidentate tn ligands; while the Cu1A and Cu1B ions are three coordinated to cyano groups. The structure can be described as formed by 18-membered “[CuI(CN)]6” planar metallocycles that are connected to their six neighbors to generate 2-D sheets; these sheets stack forming infinite hexagonal channels in which the [Cu(tn)2]2+ units are located. Magnetic measurements show an unexpected weak ferromagnetic coupling (θ = 0.239(1) K) of the CuII ions through the long and “a priori diamagnetic” –NC–CuI–CN– bridges in compound 1 and an essentially paramagnetic behavior in compound 2.  相似文献   

15.
The complex salt {[CuL2][Cu4I6]?MeCN}n (1) and the compound [Cu4L3I4]?3 MeCN (2) (L is a chiral ligand bearing a natural monoterpene (+)-3-carene moiety) were synthesized. The crystal structures of compounds 1 and 2 were determined by X-ray diffraction. The structure of compound 1 consists of complex cations [CuL2]2+ (N3O2 polyhedron is a trigonal bipyramid) and CuI coordination polymers (CuI4 polyhedron is a tetrahedron) as anions. The experimental magnetic moment μeff at 300 K is 1.90 μB, which is consistent with the X-ray diffraction data and the assumption that compound 1 is mixed-valence. The structure of compound 2 comprises a tetranuclear CuI complex, in which three Cu atoms are coordinated by two N atoms of the ligand L and two I atoms, and the fourth Cu atom is coordinated by four I atoms (coordination polyhedra are distorted tetrahedra). Compounds L and 2 were found to influence the viability of human laryngeal carcinoma cells (Hep2). The IC50 value for complex 2 (13.0±1.7 μM) is substantially smaller than IC50 for compound L (30.5±0.5 μM).  相似文献   

16.
Copper(I) coordination complexes of the anionic fluorinated ligand, hydrotris(3-trifluoromethyl-5-methyl-1-pyrazolyl)borate (L0f), i.e. the copper(I) carbonyl complex, [CuI(L0f)(CO)] (1), the copper(I) triphenylphosphine complex, [CuI(L0f)(PPh3)] (2), the copper(I) acetonitrile complex, [CuI(L0f)(NCMe)] (3), and the corresponding copper(I) triphenylphosphine complex with hydrotris(3,5-diisopropyl-1-pyrazolyl)-borate anion (L1), i.e. [CuI(L1)(PPh3)] (4), were synthesized in order to investigate the influence of the electron-withdrawing groups on the pyrazolyl rings. The structures of complexes 1, 2, and 4 were determined by X-ray crystallography. While X-ray crystallography did not show definitive trends in terms of copper(I) atom geometry, the clear influence of the electronic structure of the pyrazolyl rings is observed by spectroscopic techniques, namely, IR and multinuclear NMR spectroscopy. Finally, the relative stability of the copper(I) complexes is discussed.  相似文献   

17.
The different coordination behavior of the flexible yet sterically demanding, hemilabile P,N ligand bis(quinoline-2-ylmethyl)phenylphosphine ( bqmpp ) towards selected CuI, AgI and AuI species is described. The resulting X-ray crystal structures reveal interesting coordination geometries. With [Cu(MeCN)4]BF4, compound 1 [Cu2(bqmpp)2](BF4)2 is obtained, wherein the copper(I) atoms display a distorted square planar and square pyramidal geometry. The steric demand and π-stacking of the ligand allow for a short Cu⋅⋅⋅Cu distance (2.588(9) Å). CuI complex 2 [Cu4Cl3(bqmpp)2]BF4 contains a rarely observed Cu4Cl3 cluster, probably enabled by dichloromethane as the chloride source. In the cluster, even shorter Cu⋅⋅⋅Cu distances (2.447(1) Å) are present. The reaction of Ag[SbF6] with the ligand leads to a dinuclear compound ( 3 ) in solution as confirmed by 31P{1H} NMR spectroscopy. During crystallization, instead of the expected phosphine complex 3 , a tris(quinoline-2-ylmethyl)bisphenyl-phosphine ( tqmbp ) compound [Ag2(tqmbp)2](SbF6)2 4 is formed by elimination of quinaldine. The Au(I) compound [Au2(bqmpp)2]PF6 ( 5 ) is prepared as expected and shows a linear arrangement of two phosphine ligands around AuI.  相似文献   

18.
以3,5-二甲(丙)基-4-氨基-1,2,4-三唑为配体,与CuI在H2O/MeCN混合溶剂热合成了2个构型不同的Cu4I4超分子化合物{[Cu2(aadmtrz)I2]·CH3CN}n1)和[Cu2(dptrz)I]n2)(aadmtrz=4-((1-氨乙基)-氨基)-3,5-二甲基-1,2,4-三唑,dptrz=3,5-二丙基-1,2,4-三唑),并进行了元素分析,红外,X射线粉末衍射及单晶衍射等表征。2个配合物中Cu4I4构型不同,配合物1中,Cu4I4簇连结成一个8环椅式-椅式结构,通过配体连接成(4,4)二维菱形格子结构;而配合物2中,Cu4I4簇呈畸变的立方烷结构,构成了含有19.5%孔隙率三维孔洞聚合物,其结构可简化为(3,4)-连接的拓朴结构。同时,在常温下研究了2个配合物的固体荧光性质。  相似文献   

19.
以3,5-二甲(丙)基-4-氨基-1,2,4-三唑为配体,与CuI在H2O/MeCN混合溶剂热合成了2个构型不同的Cu4I4超分子化合物{[Cu2(aadmtrz) I2]·CH3CN}n(1)和[Cu2(dptrz) I]n(2)(aadmtrz=4-((1-氨乙基)-氨基)-3,5-二甲基-1,2,4-三唑,dptrz=3,5-二丙基-1,2,4-三唑),并进行了元素分析,红外,X射线粉末衍射及单晶衍射等表征。2个配合物中Cu4I4构型不同,配合物1中,Cu4I4簇连结成一个8环椅式-椅式结构,通过配体连接成(4,4)二维菱形格子结构;而配合物2中,Cu4I4簇呈畸变的立方烷结构,构成了含有19.5%孔隙率三维孔洞聚合物,其结构可简化为(3,4)-连接的拓朴结构。同时,在常温下研究了2个配合物的固体荧光性质。  相似文献   

20.
Developing strong visible‐light‐absorbing (SVLA) earth‐abundant photosensitizers (PSs) for significantly improving the utilization of solar energy is highly desirable, yet it remains a great challenge. Herein, we adopt a through‐bond energy transfer (TBET) strategy by bridging boron dipyrromethene (Bodipy) and a CuI complex with an electronically conjugated bridge, resulting in the first SVLA CuI PSs ( Cu‐2 and Cu‐3 ). Cu‐3 has an extremely high molar extinction coefficient of 162 260 m ?1 cm?1 at 518 nm, over 62 times higher than that of traditional CuI PS ( Cu‐1 ). The photooxidation activity of Cu‐3 is much greater than that of Cu‐1 and noble‐metal PSs (Ru(bpy)32+ and Ir(ppy)3+) for both energy‐ and electron‐transfer reactions. Femto‐ and nanosecond transient absorption and theoretical investigations demonstrate that a “ping‐pong” energy‐transfer process in Cu‐3 involving a forward singlet TBET from Bodipy to the CuI complex and a backward triplet‐triplet energy transfer greatly contribute to the long‐lived and Bodipy‐localized triplet excited state.  相似文献   

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