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1.
Two novel copper(I) complexes with Cu‐O bonds, [Cu2L2(PPh3)2](BF4)2 ( 1 ) and [Cu(L)(dppeo)](BF4) ( 2 ) ( L = 6‐(4‐diethylmethylphosphonatephenyl)‐2,2′‐bipyridine, dppeo = bis(diphenylphosphino)ethane monoxide), have been prepared and their structures characterized. In the binuclear complex 1 , the ligand L serves as tridentate donor with the N, N′ and O as coordination atoms, and the two CuI atoms are bridged through both P = O donor atoms in different ligand L with a triphenylphosphine molecule as auxiliary ligand. While in mononuclear complex 2 , both ligands L and dppeo behave as bidentate with NN from L and PO from dppeo chelating to CuI atom.  相似文献   

2.
A series of cationic/neutral copper (I) complexes, [Cu2(Hbmb)(PPh3)4] (BF4)2 ( 1a ), [Cu2(Hbmb)(DPEPhos)2](BF4)2 ( 2a ), [Cu2(Hbmb)(Xantphos)2](BF4)2 ( 3a ), [Cu2(bmb)(PPh3)4] ( 1b ), [Cu2(bmb)(DPEPhos)2] ( 2b ), [Cu2(bmb)(Xantphos)2] ( 3b ) (Hbmb = 1,4-bis (1H-benzimidazol −2-yl)benzene, PPh3 = triphenylphosphine, DPEPhos = bis[2-(diphenylphosphino)-phenyl]ether, Xantphos =4,5-bis (diphenylphosphino)-9,9′-dimethyl-xanthene), have been synthesized and characterized by IR, TGA, XRD and X-ray crystal structure analysis. The structural analysis reveals that each Cu+ in all complexes adopts an almost ideal trigonal planar geometry, with three coordinate NP2, and the C-H···π and π···π interactions are observed in the packing structures. DFT studied indicate the ingredients of the HOMOs and LUMOs for neutral copper (I) complexes 1b , 2b and 3b are different from cationic copper (I) complexes 1a , 2a and 3a , in accordance with the distribution of Mülliken atomic charges. Meanwhile, neutral copper (I) complexes 1b , 2b and 3b have fascinating broad blue-green emission bands at room temperature, while cationic copper (I) complexes 1a , 2a and 3a exhibit the existence of multiple emission peaks. Furthermore, the maximum phosphorescent lifetime and quantum yield at room temperature, for all copper (I) complexes, are 1143 μs and 8.82%, respectively. In addition, in order to measure the practical application of these complexes, the selection of complex 1b is used to fabricate the LED, which emits a bright warm-white light.  相似文献   

3.
Electrochemical and photophysical analysis of new donor–acceptor systems 2 and 3 , in which a benzothiadiazole (BTD) unit is covalently linked to a tetrathiafulvalene (TTF) core, have verified that the lowest excited state can be ascribed to an intramolecular‐charge‐transfer (ICT) π(TTF)→π*(benzothiadiazole) transition. Owing to better overlap of the HOMO and LUMO in the fused scaffold of compound 3 , the intensity of the 1ICT band is substantially higher compared to that in compound 2 . The corresponding CT fluorescence is also observed in both cases. The radical cation TTF+. is easily observed through chemical and electrochemical oxidation by performing steady‐state absorption experiments. Interestingly, compound 2 is photo‐oxidized under aerobic conditions.  相似文献   

4.
Luminescent CuI complexes have emerged as promising substitutes for phosphorescent emitters based on Ir, Pt and Os due to their abundance and low cost. The title heteroleptic cuprous complex, [9,9‐dimethyl‐4,5‐bis(diphenylphosphanyl)‐9H‐xanthene‐κ2P ,P ](2‐methylquinolin‐8‐ol‐κ2N ,O )copper(I) hexafluorophosphate, [Cu(C10H9NO)(C39H32OP2)]PF6, conventionally abbreviated as [Cu(Xantphos)(8‐HOXQ)]PF6, where Xantphos is the chelating diphosphine ligand 9,9‐dimethyl‐4,5‐bis(diphenylphosphanyl)‐9H‐xanthene and 8‐HOXQ is the N ,O‐chelating ligand 2‐methylquinolin‐8‐ol that remains protonated at the hydroxy O atom, is described. In this complex, the asymmetric unit consists of a hexafluorophosphate anion and a whole mononuclear cation, where the CuI atom is coordinated by two P atoms from the Xantphos ligand and by the N and O atoms from the 8‐HOXQ ligand, giving rise to a tetrahedral CuP2NO coordination geometry. The electronic absorption and photoluminescence properties of this complex have been studied on as‐synthesized samples, whose purity had been determined by powder X‐ray diffraction. In the detailed TD–DFT (time‐dependent density functional theory) studies, the yellow emission appears to be derived from the inter‐ligand charge transfer and metal‐to‐ligand charge transfer (M +L ′)→LCT excited state (LCT is ligand charge transfer).  相似文献   

5.
A zincic phthalocyanine (Pc) derivative functionalized with four peripheral substituted tetrathiafulvalene (TTF) units has been synthesized. The intermediates and target compound have been characterized by 1H‐nmr, 13C‐nmr, ms, EA, uv‐vis and mp. The molecular weight of H2Pc‐TTF4 can not be found in mass spectra. 1H‐nmr spectra and mp determination show both H2PC‐TTF4 and ZnPc‐TTF4 are isomer‐mixtures. Uv‐vis spectra indicate that the aggregation of H2PC‐TTF4 is solvent dependent and the introduction of Zn atom affects the solubility of the assembly.  相似文献   

6.
A series of tetrathiafulvalene (TTF)‐annulated porphyrins, and their corresponding ZnII complexes, have been synthesized. Detailed electrochemical, photophysical, and theoretical studies reveal the effects of intramolecular charge‐transfer transitions that originate from the TTF fragments to the macrocyclic core. The incremental synthetic addition of TTF moieties to the porphyrin core makes the species more susceptible to these charge‐transfer (CT) effects as evidenced by spectroscopic studies. On the other hand, regular positive shifts in the reduction signals are seen in the square‐wave voltammograms as the number of TTF subunits increases. Structural studies that involve the tetrakis‐substituted TTF–porphyrin (both free‐base and ZnII complex) reveal only modest deviations from planarity. The effect of TTF substitution is thus ascribed to electronic overlap between annulated TTF subunits rather than steric effects. The directly linked thiafulvalene subunits function as both π acceptors as well as σ donors. Whereas σ donation accounts for the substituent‐dependent charge‐transfer transitions, it is the π‐acceptor nature of the appended tetrathiafulvalene groups that dominates the redox chemistry. Interactions between the subunits are also reflected in the square‐wave voltammograms. In the case of the free‐base derivatives that bear multiple TTF subunits, the neighboring TTF units, as well as the TTF ? + generated through one‐electron oxidation, can interact with each other; this gives rise to multiple signals in the square‐wave voltammograms. On the other hand, after metalation, the electronic communication between the separate TTF moieties becomes restricted and they act as separate redox centers under conditions of oxidation. Thus only two signals, which correspond to TTF . + and TTF2+, are observed. The reduction potentials are also seen to shift towards more negative values after metalation, a finding that is considered to reflect an increased HOMO–LUMO gap. To probe the excited‐state dynamics and internal CT character, transient absorption spectral studies were performed. These analyses revealed that all the TTF–porphyrins of this study display relatively short excited‐state lifetimes, which range from 1 to 20 ps. This reflects a very fast decay to the ground state and is consistent with the proposed intramolecular charge‐transfer effects inferred from the ground‐state studies. Complementary DFT calculations provide a mechanistic rationale for the electron flow within the TTF–porphyrins and support the proposed intramolecular charge‐transfer interactions and π‐acceptor effects.  相似文献   

7.
Heteroleptic copper(I) complexes have been prepared from a macrocyclic ligand incorporating a 2,9‐diphenyl‐1,10‐phenanthroline subunit ( M30 ) and two bis‐phosphines, namely bis[(2‐diphenylphosphino)phenyl] ether (POP) and 1,3‐bis(diphenylphosphino)propane (dppp). In both cases, the diphenylphosphino moieties of the PP ligand are too bulky to pass through the 30‐membered ring of M30 during the coordination process, hence the formation of C2v‐symmetrical pseudo‐rotaxanes is prevented. When POP is used, X‐ray crystal structure analysis shows the formation of a highly distorted [Cu( M30 )(POP)]+ complex in which the POP ligand is only partially threaded through the M30 unit. This compound is poorly stable as the CuI cation is not in a favorable coordination environment due to steric constraints. By contrast, in the case of dppp, the bis‐phosphine ligand undergoes both steric and topological constraints and adopts a nonchelating coordination mode to generate [Cu2( M30 )2(μ‐dppp)](BF4)2. This compound exhibits metal‐to‐ligand charge transfer (MLCT) emission characterized by a very large Stokes’ shift (≈200 nm) that is not attributed to a dramatic structural distortion between the ground and the emitting states but to very weak MLCT absorption transitions at longer wavelengths. Accordingly, [Cu2( M30 )2(μ‐dppp)](BF4)2 shows unusually high luminescence quantum yields for CuI complexes, both in solution and in the solid state (0.5 and 7 %, respectively).  相似文献   

8.
A new series of neutral isocyanoborato rhenium(I) diimine complexes [Re(CO)3(N^N)(CNBR3)], where N^N=bpy, 4,4′‐Me2bpy, phen, 4,7‐Me2phen, 2,9‐Me2phen, 3,4,7,8‐Me4phen; R=C6F5, C6H5, Cl, 4‐ClC6H4, 3,5‐(CF3)2C6H3, with various isocyanoborate and diimine ligands of diverse electronic and steric nature have been synthesized and characterized. The X‐ray crystal structures of six complexes have also been determined. These complexes displayed intense bluish green to yellow phosphorescence at room temperature in dichloromethane solution. The photophysical and electrochemical properties of these complexes had been investigated. To elucidate the electronic structures and transitions of these complexes, DFT and TD‐DFT calculations have been performed, which revealed that the lowest‐energy electronic transition associated with these complexes originates from a mixture of MLCT [dπ(Re)→π*(N^N)] and LLCT [π(CNBR3)→π*(N^N)] transitions.  相似文献   

9.
Two ligands 1‐diphenylphosphinopyrene (1‐PyP) ( L 1 ), 1,6‐bis(diphenylphosphino)‐pyrene (1,6‐PyP) ( L 2 ) and their cyclometalated complexes [Pt(dppm)(1‐PyP‐H)]+ ( 1 ), [Pt2(dppm)2(1,6‐PyP‐H2)]2+ (dppm = bis(diphenylphosphino)methane ( 2 ), and [Pd(dppe)(1‐PyP‐H)+ (dppe = bis(diphenylphosphino)ethane) ( 3 ) are investigated theoretically to explore their electronic structures and spectroscopic properties. The ground‐ and excited‐state structures are optimized by the density functional theory (DFT) and single‐excitation configuration interaction method, respectively. At the time‐dependent DFT (TDDFT) and B3LYP level, the absorption and emission spectra in solution are obtained. As revealed from the calculations, the lowest‐energy absorptions of 1 and 3 are attributed to the mixing ligand‐to‐metal charge transfer (CT)/intraligand (IL)/ligand‐to‐ligand CT transitions, while that of 2 is attributed to the IL transition. The lowest‐energy phosphorescent emissions of the cyclometalated complexes are attributed to coming from the 3ILCT transitions. With the increase of the spin‐orbit coupling effect, the phosphorescence intensities and the emissions wavelength are correspondingly increased. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011  相似文献   

10.
The reactions of pyrimidine‐phosphine ligand N‐[(diphenylphosphino)methyl]‐2‐pyrimidinamine ( L ) with various metal salts of PtII, PdII and CuI provide three new halide metal complexes, Pt2Cl4(μ‐L)2·2CH2Cl2 ( 1 ), Pd2Cl4(μ‐L)2 ( 2 ), and [Cu2(μ‐I)2L2]n ( 3 ). Single crystal X‐ray diffraction studies show that complexes 1 and 2 display a similar bimetallic twelve‐membered ring structure, while complex 3 consists of one‐dimensional polymeric chains, which are further connected into a 2‐D supramolecular framework through hydrogen bonds. In the binuclear complexes 1 and 2 , the ligand L serves as a bridge with the N and P as coordination atoms, but in the polymeric complex 3 , both bridging and chelating modes are adopted by the ligand. The spectroscopic properties of complexes 1 ‐ 3 as well as L have been investigated, in which complex 3 exhibits intense photoluminescence originating from intraligand charge transfer (ILCT) π→π* and metal‐to‐ligand charge‐transfer (MLCT) excited states both in acetonitrile solution and solid state, respectively.  相似文献   

11.
The room‐temperature infrared and Raman spectra of a series of four isostructural polymeric salts of 2,3,6,7‐tetrakis(2‐cyanoethylthio)‐tetrathiafulvalene (TCE‐TTF) with paramagnetic (CoII, MnII) and diamagnetic (ZnII, CdII) ions, together with BF4? or ClO4? anions are reported. Infrared and Raman‐active modes are identified and assigned based on theoretical calculations for neutral and ionized TCE‐TTF using density functional theory (DFT) methods. It is confirmed that the TCE‐TTF molecules in all the materials investigated are fully ionized and interact in the crystal structure through cyanoethylthio groups. The vibrational modes related to the C?C stretching vibrations of TCE‐TTF are analyzed assuming the occurrence of electron–molecular vibration coupling (EMV). The presence of the antisymmetric C?C dimeric mode provides evidence that charge transfer takes place between TCE‐TTF molecules belonging to neighboring polymeric networks.  相似文献   

12.
The first three‐dimensional (3D) conductive single‐ion magnet (SIM), (TTF)2[Co(pdms)2] (TTF=tetrathiafulvalene and H2pdms=1,2‐bis(methanesulfonamido)benzene), was electrochemically synthesised and investigated structurally, physically, and theoretically. The similar oxidation potentials of neutral TTF and the molecular precursor [HNEt3]2[M(pdms)2] (M=Co, Zn) allow for multiple charge transfers (CTs) between the SIM donor [M(pdms)2]n? and the TTF.+ acceptor, as well as an intradonor CT from the pdms ligand to Co ion upon electrocrystallisation. Usually TTF functions as a donor, whereas in our system TTF is both a donor and an accepter because of the similar oxidation potentials. Furthermore, the [M(pdms)2]n? donor and TTF.+ acceptor are not segregated but strongly interact with each other, contrary to reported layered donor–acceptor electrical conductors. The strong intermolecular and intramolecular interactions, combined with CT, allow for relatively high electrical conductivity even down to very low temperatures. Furthermore, SIM behaviour with slow magnetic relaxation and opening of hysteresis loops was observed. (TTF)2[Co(pdms)2] ( 2‐Co ) is an excellent building block for preparing new conductive SIMs.  相似文献   

13.
In this paper, we report the synthesis, crystal structure, photophysical properties, and electronic nature of a phosphorescent Cu(I) complex of [Cu(TBT)(POP)]BF4, where TBT and POP stand for 4,5,9,14-tetraaza-benzo[b]triphenylene and bis(2-(diphenylphosphanyl)phenyl) ether, respectively. [Cu(TBT)(POP)]BF4 renders a red phosphorescence peaking at 622 nm, with a long excited-state lifetime of 13.2 μs. Density functional calculation reveals that the emission comes from a triplet metal-to-ligand-charge-transfer excited state. We electrospun composite nanofibers of [Cu(TBT)(POP)]BF4 and polystyrene, hoping to explore the possibility of replacing precious-metal-based oxygen sensors with cheap Cu-based ones. The finally obtained samples with average diameter of ~700 nm exhibit a maximum sensitivity of 5.8 toward molecular oxygen with short response/recovery time (5/13 s) due to the large surface-area-to-volume ratio of nanofibrous membranes. No photobleaching is detected in these samples. All these results suggest that phosphorescent Cu(I) complexes doped nanofibrous membranes are promising candidates for low-cost and quick-response oxygen-sensing materials.  相似文献   

14.
The two molecular triads 1a and 1b consisting of a porphyrin (P) covalently linked to a fullerene (C60) electron acceptor and tetrathiafulvalene (TTF) electron‐donor moiety were synthesized, and their photochemical properties were determined by transient absorption and emission techniques. Excitation of the free‐base‐porphyrin moiety of the TTF−P2 H−C60 triad 1a in tetrahydro‐2‐methylfuran solution yields the porphyrin first excited singlet state TTF−1P2 H−C60, which undergoes photoinduced electron transfer with a time constant of 25 ps to give TTF−P2 H.+−C60.−. This intermediate charge‐separated state has a lifetime of 230 ps, decaying mainly by a charge‐shift reaction to yield a final state, TTF.+−P2 H−C60.−. The final state has a lifetime of 660 ns, is formed with an overall yield of 92%, and preserves ca. 1.0 eV of the 1.9 eV inherent in the porphyrin excited state. Similar behavior is observed for the zinc analog 1b . The TTF‐PZn.+−C60.− state is formed by ultrafast electron transfer from the porphyrinatozinc excited singlet state with a time constant of 1.5 ps. The final TTF.+−PZn−C60.− state is generated with a yield of 16%, and also has a lifetime of 660 ns. Although charge recombination to yield a triplet has been observed in related donor‐acceptor systems, the TTF.+−P−C60.− states recombine to the ground state, because the molecule lacks low‐energy triplet states. This structural feature leads to a longer lifetime for the final charge‐separated state, during which the stored energy could be harvested for solar‐energy conversion or molecular optoelectronic applications.  相似文献   

15.
A new series of bimetallic bis(diphenylphosphino)acetylene-bridged copper(I) 1,10-phenanthroline complexes, [Cu2(dppa)2(L)2](BF4)2; L?=?1,10-phenanthroline (1); 4-methyl-1,10-phenanthroline (2); 4,7-dimethyl-1,10-phenanthroline (3); and 2,9-dimethyl-1,10-phenanthroline (4), have been prepared and characterized by spectroscopic methods. The X-ray structures of 1 and 4 were determined. The structures consist of centrosymmetric bimetallic 10-membered chair-like dimetallacycles. In 1, intermolecular C–H?π interactions result in bending of the phenanthroline ligand and sterically induced lengthening of one Cu–P bond. In 1–4, the 31P NMR downfield coordination shift, relative to the free ligand, correlates with the basic strength of the 1,10-phenanthroline ligands.  相似文献   

16.
《Chemical physics letters》2003,367(3-4):463-467
Supramolecular self-assembling processes of nitrogen bidendated heterocycles are fundamental for the understanding of rules which predestine to their spontaneous formation. In our approach ab initio DFT method has been used to resolve six Cu(I) complexes. The collected data show that only four structures converged into a quasi-tetrahedral [L2Cu][BF4] geometry. A special feature in case of the [(bpy–bpz)2Cu][BF4] hetero-complex, not observed in case of the corresponding Cu(I) homo-complexes, is the increased participation of p orbitals of the Cu+ to the HOMO.  相似文献   

17.
Chiral Half‐sandwich Pentamethylcyclopentadienyl Rhodium(III) and Iridium(III) Complexes with Schiff Bases from Salicylaldehyde and α‐Amino Acid Esters [1] A series of diastereoisomeric half‐sandwich complexes with Schiff bases from salicylaldehyde and L‐α‐amino acid esters including chiral metal atoms, [(η5‐C5H5)(Cl)M(N,O‐Schiff base)], has been obtained from chloro bridged complexes [(η5‐C5Me5)(Cl)M(μ‐Cl)]2 (M = Rh, Ir). Abstraction of chloride from these complexes with Ag[BF4] or Ag[SO3CF3] affords the highly sensitive compounds [(η5‐C5Me5)M(N,O‐Schiff base]+X? (M = Rh, Ir; X = BF4, CF3SO3) to which PPh3 can be added under formation of [(η5‐C5Me5)M(PPh3)(N,O‐Schiff base)]+X?. The diastereoisomeric ratio of the complexes ( 1 ‐ 7 and 11 ‐ 12 ) has been determined from NMR spectra.  相似文献   

18.
New Copper Complexes Containing Phosphaalkene Ligands. Molecular Structure of [Cu{P(Mes*)C(NMe2)2}2]BF4 (Mes* = 2,4,6‐tBu3C6H2) Reaction of equimolar amounts of the inversely polarized phosphaalkene tBuP=C(NMe2)2 ( 1a ) and copper(I) bromide or copper(I) iodide, respectively, affords complexes [Cu3X3{μ‐P(tBu)C(NMe2)2}3] ( 2 ) (X =Br) and ( 3 ) (X = I) as the formal result of the cyclotrimerization of a 1:1‐adduct. Treatment of 1a with [Cu(L)Cl] (L = PiPr3; SbiPr3) leads to the formation of compounds [CuCl(L){P(tBu)C(NMe2)2}] ( 4a ) (L = PiPr3) and ( 4b ) (L = SbiPr3), respectively. Reaction of [(MeCN)4Cu]BF4 with two equivalents of PhP=C(NMe2)2 ( 1b ) yields complex [Cu{P(Ph)C(NMe2)2}2]BF4 ( 5b ). Similarly, compounds [Cu{P(Aryl)C(NMe2)2}2]BF4 ( 5c (Aryl = Mes and 5d (Aryl = Mes*)) are obtained from ArylP=C(NMe2)2 ( 1c : Aryl = Mes; 1d : Mes*) and [(MeCN)4Cu]BF4 in the presence of SbiPr3. Complexes 2 , 3 , 4a , 4b , and 5b‐5d are characterized by means of elemental analyses and spectroscopy (1H‐, 13C{1H}‐, 31P{1H}‐NMR). The molecular structure of 5d is determined by X‐ray diffraction analysis.  相似文献   

19.
Substitution of silver complex of 2‐chloro‐7‐(mesitylimidazolylidenylmethyl)naphthyridine (NpNHC) with palladium(II), rhodium(I) and iridium(I) metal precursors provided [Pd(C ,N ‐NpNHC)(η3‐allyl)](BF4) ( 5 ), RhCl(COD)(C ‐NpNHC) ( 6a ) and IrCl(COD)(C ‐NpNHC) ( 6b ), respectively. Abstraction of chloride from 6a and 6b with AgBF4 provided the chelation complexes [Rh(COD)(C ,N ‐NpNHC)](BF4) ( 7a ) and Ir(COD)(C ,N ‐NpNHC)(BF4) ( 7b ), respectively. All complexes were characterized using NMR and elemental analyses and the structural details of 5 and 6a were further confirmed using X‐ray crystallography. In catalytic activity studies, complex 5 was found to be an effective catalyst in the hydrogen‐transfer reduction of α,β‐unsaturated carbonyl compounds into the corresponding saturated carbonyl compounds.  相似文献   

20.
Diphosphine‐bridged dicopper(I) acetate complexes [Cu2(μ‐dppm)2(μ‐OAc)]X ( 2 X; X? = , ) and [Cu2(μ‐dppm)2(μ‐OAc)(MeCN)]X ( 4 X) were prepared and the structures of 2 (PF6 ) and 4 (PF6 ) determined by X‐ray crystallography. The ground‐state geometries of [Cu2(μ‐dppm)2(μ‐OAc)]+ and [Cu2(μ‐dppm)2(μ‐OAc)(L)]+ (L = py, MeCN, THF, acetone, MeOH) were also obtained using density functional theory (DFT). The increased Cu – Cu distances found experimentally and theoretically by comparing the structures of cation [Cu2(μ‐dppm)2(μ‐OAc)]+ and its derivatives [Cu2(μ‐dppm)2(μ‐OAc)(L)]+ reflect the binding of various sigma donors (L). When using [Cu2(μ‐dppm)2(μ‐OAc)]+ as a structure sensor, the electron‐donating strength of a sigma donor can be quantitatively expressed as a DFT‐calculated Cu – Cu distance with the relative strength in the order py > MeCN > THF > acetone > MeOH, as determined.  相似文献   

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