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1.
The 2D porous copper(Ⅰ) complex with 1,3-dicyanobenzene (DCB), [Cu(DCB)2](PF6)(Me2CO) 1, exhibits channels along axis c, in which one molecule acetone and one anion PF6 per formula unit are included respectively. The reversible incorporation of guest acetone and acetonitrile, as well as the anion exchange from PF6^- to BF4^- or CF3SO3^-, was investigated by thermogravimetric (TG) analysis, ^1H NMR spectra and/or infrared absorption spectroscopy. Additionally, the incorporation of benzene and toluene into complex 1 was also discussed. Complex 1 exhibited size selectivity for guest inclusion or anion exchange.  相似文献   

2.
合成了邻菲罗啉衍生物联吡啶[3,2-a:2',3'-c]-7-氮杂-吩嗪(dpapz)及其铜(I)配合物[Cu(dpapz)2]PF6, 利用核磁共振氢谱(1H NMR), 傅里叶变换红外(FTIR)光谱, 高分辨质谱(HR ESI-MS)等对合成的化合物进行了表征.采用紫外-可见吸收光谱,荧光光谱, DNA熔解温度实验和循环伏安方法研究了dpapz和[Cu(dpapz)2]PF6与小牛胸腺DNA(CT DNA)的相互作用. 配体dpapz与小牛胸腺DNA(CT DNA)作用时未观察到吸收峰红移并且减色效应较小(<30%), 且DNA熔解温度也上升较小(ΔTm=7.8 ℃), 说明dpapz以沟槽结合的方式与CT DNA相互作用. 而[Cu(dpapz)2]PF6与CT DNA作用时, 可观测到较小的吸收峰红移(2-3 nm)和较大的减色效应(>50%), 同时DNA熔解温度上升较大(ΔTm=11.1 ℃), 表明[Cu(dpapz)2]PF6以静电相互作用和部分扦插的方式与DNA结合. 溴乙锭(EB)荧光竞争实验和循环伏安实验进一步证实了这一结论. 配体dpapz和[Cu(dpapz)2]PF6与DNA的结合常数分别为2.88×105和5.32×105 mol·L-1. 光照条件下, [Cu(dpapz)2]PF6产生单重态氧的能力与dpapz相当, 但产生超氧负离子自由基的能力要弱于dpapz. 活性氧猝灭实验表明, 超氧负离子自由基、单重态氧和羟基自由基均参与了dpapz和[Cu(dpapz)2]PF6对DNA的光损伤作用. [Cu(dpapz)2]PF6对DNA的亲和性要高于对dpapz的, 使得[Cu(dpapz)2]PF6对质粒DNA的光损伤效率明显强于dpapz.  相似文献   

3.
We report the synthesis and characterization of two iridium polypyridyl complexes, [Ir(deeb)2Cl2](PF6) and [Ir(deeb)2(dpp)](PF6)3, where deeb?=?diethyl-2,2′-bipyridine-4,4′-dicarboxylate and dpp?=?2,3-bis(2-pyridyl)pyrazine. From 1H NMR spectral data, the two deeb ligands are attached to Ir cis to each other. Mass spectra contain fragmentation patterns of the (M-PF6)+ and (M-3PF6)3+ molecular ions for [Ir(deeb)2Cl2](PF6) and [Ir(deeb)2(dpp)](PF6)3, respectively. The electronic absorption spectrum of [Ir(deeb)2Cl2](PF6) shows maxima at 308?nm and 402?nm, which are assigned as 1π?→?π* and metal-to-ligand charge transfer transitions, respectively. [Ir(deeb)2(dpp)](PF6)3 exhibits peaks due to 1π?→?π* transitions at 322?nm and 334?nm. [Ir(deeb)2Cl2](PF6) has emission peaks at 538?nm in acetonitrile and 567?nm in the solid state, with lifetimes of 1.71?µs and 0.35?µs, respectively. [Ir(deeb)2Cl2](PF6) has an unusually higher quantum yield than analogous compounds. [Ir(deeb)2(dpp)](PF6)3 has emission peaks at 540?nm in acetonitrile and 599?nm in the solid state with lifetimes of 1.23?µs and 0.14?µs, respectively. Cyclic voltammetry of [Ir(deeb)2Cl2](PF6) yields two reversible couples at ?0.72 and ?0.87?V versus Ag/AgCl, both corresponding to deeb ligand reductions, and a quasi-reversible couple at ?1.48?V corresponding to Ir3+/+ reduction. Electrochemical reduction of [Ir(deeb)2(dpp)](PF6)3 yields couples at ?0.38, ?0.54, ?0.71, and ?1.33?V, assigned as deeb0/?, deeb0/?, dpp0/?, and Ir3+/+ reductions, respectively.  相似文献   

4.
The complexes [Ru(bpy)2(pyESO)](PF6)2 and [Os(bpy)2(pyESO)](PF6)2, in which bpy is 2,2′‐bipyridine and pyESO is 2‐((isopropylsulfinyl)ethyl)pyridine, were prepared and studied by 1H NMR, UV–visible and ultrafast transient absorption spectroscopy, as well as by electrochemical methods. Crystals suitable for X‐ray structural analysis were grown for [Ru(bpy)2(pyESO)](PF6)2. Cyclic voltammograms of both complexes provide evidence for S→O and O→S isomerization as these voltammograms are described by an ECEC (electrochemical‐chemical electrochemical‐chemical) mechanism in which isomerization follows Ru2+ oxidation and Ru3+ reduction. The S‐ and O‐bonded Ru3+/2+ couples appear at 1.30 and 0.76 V versus Ag/AgCl in propylene carbonate. For [Os(bpy)2(pyESO)](PF6)2, these couples appear at 0.97 and 0.32 V versus Ag/AgCl in acetonitrile, respectively. Charge‐transfer excitation of [Ru(bpy)2(pyESO)](PF6)2 results in a significant change in the absorption spectrum. The S‐bonded isomer of [Ru(bpy)2(pyESO)]2+ features a lowest energy absorption maximum at 390 nm and the O‐bonded isomer absorbs at 480 nm. The quantum yield of isomerization in [Ru(bpy)2(pyESO)]2+ was found to be 0.58 in propylene carbonate and 0.86 in dichloroethane solution. Femtosecond transient absorption spectroscopic measurements were collected for both complexes, revealing time constants of isomerizations of 81 ps (propylene carbonate) and 47 ps (dichloroethane) in [Ru(bpy)2(pyESO)]2+. These data and a model for the isomerizing complex are presented. A striking conclusion from this analysis is that expansion of the chelate ring by a single methylene leads to an increase in the isomerization time constant by nearly two orders of magnitude.  相似文献   

5.
《Supramolecular Science》1996,3(4):215-220
A new tetracationic cyclophane, cyclobis(4,4′-azopyridinium-p-phenylene) (2.4PF6), was synthesized via template-directed synthesis and characterized by MS and NMR spectroscopy. For the preparation of π-electron-deficient 2.4PF6, the use of π-electron-rich templates such as 1,4-bis[2-(2-hydroxyethoxy)ethoxy]-benzene (4) and 1,5-bis[2-(2-hydroxyethoxy)ethoxy]naphthalene (5) enhanced the cyclophane formation in 17 and 19% yields, respectively. 1H NMR spectra of the reaction mixture revealed that the cyclophane precursor 1.2PF6 formed supramolecular assembling complexes with hydroquinone derivatives 4 and 5 before the ring formation. The intermolecular charge transfer interaction and the stability constants (Ka) of complexes generated between the electron-acceptor 2.4PF6 and electron-donors 1,4-dimethoxybenzene 3, 4, and 5 were evaluated using UV-vis. spectroscopy and spectroscopic titration. The absorption bands attributable to CT interactions were centred at 580 nm for 3, 635 nm for 4, and 646 nm for 5, with stability constants of 17 ± 2, 2100 ± 200, and 2400 ± 300, respectively.  相似文献   

6.
Some oxidative addition reactions of (CH3)5C5Rh(PF3)2 with various iodine compounds are described. Iodine reacts with (CH3)5C5Rh(PF3)2 in benzene at room temperature to give the deep red crystalline diiodide (CH3)5C5Rh(PF3)I2. The perfluoroalkyl iodides RfI (Rf = CF3, C2F5, n-C3F7, and n-C7F15) react with (CH3)5C5Rh(PF3)2 in benzene at room temperature to give the orange to deep red (CH3)5C5Rh(PF3)(Rf)I (Rf = CF3, C2F5, n-C3F7, and n-C7Fl5). The IR and proton and fluorine NMR spectra of these new (pentamethylcyclopentadienyl)rhodium-trifluorophosphine complexes are discussed.  相似文献   

7.
The IR spectra of gaseous and solid (PF2)2O has been recorded from 80 to 1200 cm?1. The Raman spectra of gaseous, liquid and solid (PF2)2O have also been obtained (30–1000 cm?1). The spectra of the fluid phases indicate the presence of at least two conformers. The spectrum of the solid phase can readily be interpreted on the basis of a single conformer possessing a symmetry lower than C2v. A vibrational assignment is proposed for all normal modes except the PF2 torsions. The results are compared with similar data of related compounds. There appear to be two molecules per primitive cell based upon the low-frequency Raman data.  相似文献   

8.
Field desorption mass spectra are reported for a range of [M(CO)3(η-arene)]X (MMn or Re, XBF4 or PF6) salts. In most cases the spectra are simple, being dominated by molecular, [M]+·, [M + 1]+, and [MCO]+ ions for the cationic part of their structure. However, with the π-chloroarene complexes [Mn(CO)3(η-ClC6H5)]PF6 and [Mn(CO)3(η-1-Cl, 4-MeC6H4)]PF6, facile loss of the chloro substituent and further fragmentation leads to unusually complex spectra, which include strong peaks arising from recombination of fragment species. Cluster ions are also noted in several cases, allowing identification of the anion.  相似文献   

9.
Light scattering and far infrared absorption spectra of CCl4, C2Cl4, C6H12, CHCl3, and CH2Cl2 in the liquid phase have been obtained in the range of 2 – 200 and 20 – 200 cm?1 respectively. The energy absorption spectra obtained by the two techniques and the corresponding relaxation times were compared for each liquid. We observe systematic differences between the energy absorption profiles obtained from the light scattering spectra and the far infrared absorption spectras. We also find generally shorter relaxation times from the infrared absorption spectra. Despite the similarity of the physical processes leading to light scattering and to far infrared absorption some significant differences are observed (ref. 1,2).  相似文献   

10.
The absorption spectra of liquid F2, NF3, N2F4, CF4, BF3, NF3, SF6 have been obtained at diminished temperatures in the near ultra-violet region of the spectrum. It is shown that the absorption spectrum does not differ from the spectra in the gaseous phase, therefore the elementary absorption act is characterized by the cross section of photon absorption by an individual molecule. The absorption cross sections of the above mentioned molecules are represented in the liquid phase, which do not differ strongly from absorption cross sections of these molecules in the gaseous phase. The dependence of the absorption cross sections of liquid fluorine on its concentrations in solutions with N2, Ar, NF3, O2 at - 196°C has been studied. The cross sections of photon absorption by the fluoride molecule in different liquid media with small fluorine concentrations have been obtained.  相似文献   

11.
On the Crystal Structures of CH3PF2H+AsF6? and CH3PF2H+SbF6? and a simple Method for Preparation of CH3PF2 A simple method for preparation of CH3PF2 from CH3PCl2 is reported. The phosphonium salts CH3PF2H+MF6? are obtained by the reaction of CH3PCl2 with superacidic systems HF/MF5 (M = As, Sb). CH3PF2H+SbF6? crystallizes in the space group P1 with a = 548.4(4) pm, b = 695.5(8) pm, c = 960.2(9) pm, α = 94.68(5)°, β = 97.19(6)°, γ = 94.41(6)° and Z = 2. CH3PF2H+SbF6? crystallizes in P1 with a = 554.3(3), b = 724.2(4), c = 970.4(5), α = 94.73(4)°, β = 96.14(5)°, γ = 95.30(4)°.  相似文献   

12.
Phosphorus pentafluoride was reported long ago to give adducts 2 PF5 ·5 NH3 (1) and nNH3·PF5 (n= 1 ? 4) (2). None of the compounds was characterised in detail. Repeating the reaction of PF5 and NH3 we found the adduct H3N·PF5, 1, in 8% yield besides (H2N) 2PF3 (3) and NH4PF6. However, HF and (F2P=N)3 gave 1 in 41% yield. The 1H, 19F, and 31P n.m.r. spectra of 1 exhibit 14NH, 14NPF(cis), and 14NP coupling. The x-ray structure determination shows almost perfect octahedral geometry at phosphorus with a PN bond length of 1.842 ā. Compound 1 is soluble in water without decomposition. Treatment with NH3 leads to the anion H2NPF5?. Upon heating 1 forms in good yield H2NPF4 and NH4PF6. Without a solvent 1 and NH3 react to give (H2N) 2PF3. A mechanism for the ammonolysis of PF5 is proposed.  相似文献   

13.
The syntheses and crystal structures of two iridium complexes, (dfppy)2IrPyCl (1) and [(dfppy)2Ir(Py)2]PF6 (2), are reported. 1 can selectively detect Ag+ with UV–vis absorption and emission spectra. In the presence of Ag+, the obvious decrease of the luminescence intensity at 476?nm was observed, which could be monitored by the naked eyes. The phosphorescence quantum yield decreases from 0.024 to 0.012. No obvious changes of the luminescence intensity were observed upon addition of a large excess of other transition metal ions. Due to the strong interaction between chloride and Ag+, the special chemical reaction induced by Ag+ is responsible for the significant change of absorption and luminescence spectra.  相似文献   

14.
Nano-emulsions containing task-special ionic liquid ([NH2ebim][PF6]) were prepared by spontaneous emulsification. The stability of nano-emulsions was investigated by analysis of droplet size. The microstructure of the mixed solvent including the Triton X-100, n-butanol, and [NH2ebim][PF6] was demonstrated based on macular dynamic simulation. The results indicate that nano-emulsions are relatively stable to the droplet growth at static storage, but unstable under high centrifugal force. Simulation results from the macular dynamic calculation show that [NH2ebim][PF6] locates in the hydrophobic layer of Triton X-100 and n-butanol, which is available for enhancing CO2 mass transfer in an absorption process. Nano-emulsions were used as the absorbent to absorb CO2 in absorption experiments, and the absorption rates were investigated. The results show that nano-emulsion containing [NH2ebim][PF6] can enhance CO2 absorption rate compared to the system that pure water was used as the absorbent. The reason is attributed to the reversible chemical reaction between [NH2ebim][PF6] and CO2 on the interface of oil and water, which decreases the concentration of CO2 in the bulk so as to increase the mass transfer driving force between gas and liquid. Therefore, the chemical reaction on the interface of oil and water promotes the absorption process.  相似文献   

15.
《Chemical physics letters》1987,134(5):497-501
Polarized absorption spectra of neat single-crystal [Ru(bpy)3](PF6)2 at 300 and 5 K are presented. The spectra show pronounced vibronic structure and it is possible to assign the vibrations to known Raman frequencies. Furthermore, the different electronic states corresponding to the vibronic transitions are identified and assigned. The assignment of the lowest excited states - observed in absorption - agrees with an earlier classification of the emitting states. In particular, the Ec-polarized transition A'1 ⇌ 2E' (classified in D'3), at 17816 cm−1, is found at the same energy (experimental error: ± 1 cm−1) in emission and absorption and represents a zero-phonon, zero-vibron transition. The low-energy part of the E¦¦c-polarized spectrum (below ≈ 24000 cm−1) is not dominated by a series of different electronic states but by a 1600 cm−1 progression with zero-vibron transition at 18770 cm−1.  相似文献   

16.
Synthesis of [Mn(OBTTAP)], 1 and bichromophoric, di- and pentanuclear complexes with diimine-ruthenium(II) of the type [{Mn(OBTTAP)}{Ru(bpy)2}][PF6]2, 2, [{Mn(OBTTAP)}{Ru(phen)2}][PF6]2, 3, [{Mn(OBTTAP)}{RuCp(PPh3)}][PF6], 4, [{Mn(OBTTAP)}{Ru(bpy)2}4]- [PF6]8, 5, [{Mn(OBTTAP)}{Ru(phen)2}4][PF6]8, 6 and [{Mn(OBTTAP)}{RuCp(PPh3)}4][PF6]4, 7, (OBTTAP = octakis(benzylthio)tetraazaporphyrin) have been described. They were characterized using IR, 1H NMR, UV–visible, and mass spectral data. In the electronic absorption spectra the relative intensities and positions of the Soret and Q-bands, in the di- and pentanuclear complexes were observed shifted vis-à-vis that in the precursor complex 1. They all exhibit strong S2 emission. The emission intensity of the equimolar solutions of complexes 2, 3, 4 and 7 were found to be significantly higher than that of 1. The excitation-emission behaviors of the complexes are indicative of interchromophore energy transfer. Complexes 27 exhibited good electrode activity, particularly with multiple reversible redox waves in oxidative CV scans. The OBTTAP ring oxidations were observed as one or two reversible waves, depending upon number and nature of the peripheral metal units. Particularly, with four (bpy)2RuII units bonded to the [Mn(OBTTAP)] periphery, it was observed as two reversible, one electron oxidation waves at E 1/2 0.81 and 1.02 V vs. Ag/AgCl. Also the Ru(II)/Ru(III) oxidations were observed at significantly lower potential, in this complex, at E1/2 0.49 V vs Ag/AgCl due to weaker π-inteaction with dπ(S) orbitals.  相似文献   

17.
The synergy of push–pull substitution and enlarged ligand bite angles has been used in functionalized heteroleptic bis(tridentate) polypyridine complexes of ruthenium(II) to shift the 1MLCT absorption and the 3MLCT emission to lower energy, enhance the emission quantum yield, and to prolong the 3MLCT excited‐state lifetime. In these complexes, that is, [Ru(ddpd)(EtOOC‐tpy)][PF6]2, [Ru(ddpd‐NH2)(EtOOC‐tpy)][PF6]2, [Ru(ddpd){(MeOOC)3‐tpy}][PF6]2, and [Ru(ddpd‐NH2){(EtOOC)3‐tpy}][PF6]2 the combination of the electron‐accepting 2,2′;6′,2′′‐terpyridine (tpy) ligand equipped with one or three COOR substituents with the electron‐donating N,N′‐dimethyl‐N,N′‐dipyridin‐2‐ylpyridine‐2,6‐diamine (ddpd) ligand decorated with none or one NH2 group enforces spatially separated and orthogonal frontier orbitals with a small HOMO–LUMO gap resulting in low‐energy 1MLCT and 3MLCT states. The extended bite angle of the ddpd ligand increases the ligand field splitting and pushes the deactivating 3MC state to higher energy. The properties of the new isomerically pure mixed ligand complexes have been studied by using electrochemistry, UV/Vis absorption spectroscopy, static and time‐resolved luminescence spectroscopy, and transient absorption spectroscopy. The experimental data were rationalized by using density functional calculations on differently charged species (charge n=0–4) and on triplet excited states (3MLCT and 3MC) as well as by time‐dependent density functional calculations (excited singlet states).  相似文献   

18.
Vibrational and electronic absorption spectra of PyHI3, PyHIBr2, PyHICl2, PyHBr3 and PyHBrCl2 are presented and explained in terms of the vibrations and electronic transitions, respectively, of the pyridinium and trihalide ions. Two compounds, PyHI3 and PyHBr3, show charge transfer bands in the absorption spectra of the solids, and the vibrational spectrum of the PyH+ ion in solid PyHBr3 differs from the normal PyH+ spectrum. PyHBr3 as well as PyHI3 contains asymmetric trihalide ions in the solid state, as can be concluded from the Raman and infrared spectra.  相似文献   

19.
Addition of [C7H7][PF6] to iron, ruthenium or osmium alkynyl complexes has given eight cationic cycloheptatrienylvinylidene derivatives [M{C C(C7H7)R}(L)2 (η-C5H5)][PF6] (M = Fe, Ru or Os; R = Me, Pr, Ph or C6F5; L = PPh3, L2 = dppm or dppe; but not all combinations). With Fe(C2Ph)(CO)2(η-C5H5), only [Fe(CO)2(thf)(η-C5H5)][PF6] was obtained. Reactions of the new complexes are characterised by loss of the C7H7 group. The NMR spectra and FAB mass spectra are described in detail.  相似文献   

20.
Cyclometallated ruthenium complexes typically exhibit red-shifted absorption bands and lower photolability compared to their polypyridyl analogues. They also have lower symmetry, which sometimes makes their synthesis challenging. In this work, the coordination of four N,S bidentate ligands, 3-(methylthio)propylamine (mtpa), 2-(methylthio)ethylamine (mtea), 2-(methylthio)ethyl-2-pyridine (mtep), and 2-(methylthio)methylpyridine (mtmp), to the cyclometallated precursor [Ru(bpy)(phpy)(CH3CN)2]+ (bpy=2,2′-bipyridine, Hphpy=2-phenylpyridine) has been investigated, furnishing the corresponding heteroleptic complexes [Ru(bpy)(phpy)(N,S)]PF6 ([ 2 ]PF6–[ 5 ]PF6, respectively). The stereoselectivity of the synthesis strongly depended on the size of the ring formed by the Ru-coordinated N,S ligand, with [ 2 ]PF6 and [ 4 ]PF6 being formed stereoselectively, but [ 3 ]PF6 and [ 5 ]PF6 being obtained as mixtures of inseparable isomers. The exact stereochemistry of the air-stable complex [ 4 ]PF6 was established by a combination of DFT, 2D NMR, and single-crystal X-ray crystallographic studies. Finally, [ 4 ]PF6 was found to be photosubstitutionally active under irradiation with green light in acetonitrile, which makes it the first cyclometallated ruthenium complex capable of undergoing selective photosubstitution of a bidentate ligand.  相似文献   

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