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1.
The reactions of 4,5,6,7‐tetrathiocino‐[1,2‐b:3,4‐b′]‐1,3,8,10‐tetrasubstituted‐diimidazolyl‐2,9‐dithiones (R2,R′2‐todit; 1 : R=R′=Et; 2 : R=R′=Ph; 3 : R=Et, R′=Ph) with Br2 exclusively afforded 1:1 and 1:2 “T‐shaped” adducts, as established by FT‐Raman spectroscopy and single‐crystal X‐ray diffraction in the case of complex 1? 2 Br2. On the other hand, the reactions of compounds 1 – 3 with molecular I2 provided charge‐transfer (CT) “spoke” adducts, among which the solvated species 3? 2 I2 ? (1?x)I2 ? x CH2Cl2 (x=0.94) and ( 3 )2 ? 7 I2 ? x CH2Cl2, (x=0.66) were structurally characterized. The nature of all of the reaction products was elucidated based on elemental analysis and FT‐Raman spectroscopy and supported by theoretical calculations at the DFT level.  相似文献   

2.
Two new copper(II) carboxylate complexes with 2,2′‐bipyridine and para‐nitrophenyl acetate (complex 1 ) and phenyl acetate (complex 2 ) have been synthesized; isolated in quantitative yield; and characterized using fourier‐transform infrared spectroscopy (FT‐IR), electron paramagnetic resonance, absorption spectroscopy, electrochemistry, and powder and single crystal X‐ray diffraction (XRD) techniques. Being mononuclear, the geometry around copper in complex 1 is a Jahn–Teller distorted octahedral, while complex 2 is binuclear with slightly distorted square pyramidal geometry around both copper ions. Powder XRD indicated several peaks in spectra of both complexes, which coincided with their theoretical spectra. FT‐IR results of the carboxylate stretching frequency were in accordance with the single crystal structure data. Electron paramagnetic resonance spectra of complexes 1 and 2 yielded g values of 2.06161 and 2.24623 and 1.94959, respectively, indicating a localized electron in b1 (d x2y2‐orbital). Ultra‐violet (UV)–visible spectroscopy and electrochemistry helped in characterization, as well as in deoxyribonucleic acid (DNA)‐binding ability of the complexes, yielding DNA‐binding constant values = 1.351 × 104 and 1.361 × 104 and 1.820 × 104 and 2.426 × 104 M?1, respectively, for complexes 1 and 2 . The complexes demonstrate good biological potential.  相似文献   

3.
Plating battery electrodes typically deliver higher specific capacity values than insertion or conversion electrodes because the ion charge carriers represent the sole electrode active mass, and a host electrode is unnecessary. However, reversible plating electrodes are rare for electronically insulating nonmetals. Now, a highly reversible iodine plating cathode is presented that operates on the redox couples of I2/[ZnIx(OH2)4?x]2?x in a water‐in‐salt electrolyte. The iodine plating cathode with the theoretical capacity of 211 mAh g?1 plates on carbon fiber paper as the current collector, delivering a large areal capacity of 4 mAh cm?2. Tunable femtosecond stimulated Raman spectroscopy coupled with DFT calculations elucidate a series of [ZnIx(OH2)4?x]2?x superhalide ions serving as iodide vehicles in the electrolyte, which eliminates most free iodide ions, thus preventing the consequent dissolution of the cathode‐plated iodine as triiodides.  相似文献   

4.
Three distinct AgI‐DMAP [DMAP = 4‐(dimethylamino)pyridine] coordination polymers [Ag2I2(DMAP)2]n ( 1 ), [Ag2(CN)2(DMAP)2.5 · DMAP]n ( 2 ), and [Ag(SCN)(DMAP)]n ( 3 ) were constructed by monatomic I, diatomic CN, and triatomic SCN bridges, respectively. 1 – 3 were determined by FT‐IR spectroscopy, elemental analyses, TGA, powder and single‐crystal X‐ray diffraction. 1 exhibits a 1D wavelike chain structure, sustained by 3‐connected I bridges, whereas 2 shows a unique 1D single‐ and double‐strand alternating chain, supported by 3‐connected CN bridges. Compound 3 has a 2D 3‐connected network architecture, fabricated by 3‐connected SCN bridges, and exhibits a (4 · 82) topology. The luminescence and nitrobenzene sensing properties of 1 – 3 were explored in 2‐propanol suspensions, which revealed that compounds 1 – 3 exhibit DMAP originated luminescence emissions and are highly sensitive for nitrobenzene detection.  相似文献   

5.
Metal–metal bonding interactions have been employed as an efficient strategy to generate a number of unique gold(I) metallo‐macrocycles with fascinating functions. The self‐assembly, crystal structure and emission property of novel nest‐like tetramer 14 , namely, {[Au4(μ‐dppm)2(μ‐dctp2?)](BF4)2}4 ? (CH3CN)2 (dppm=bis(diphenylphosphino)methane, dctp2?=N,N′‐bis(dicarbodithioate)‐2,11‐diaza[3.3]paracyclophane) is reported. The complex has been characterized by single‐crystal X‐ray diffraction analysis, 1H NMR spectroscopy, 13C NMR spectroscopy, and CSI‐MS spectrometry. The aggregate demonstrates the sixteen gold(I) atoms are arranged in a ring with a circumference of 50.011(68) Å generated by AuI???AuI attractions. UV/visible and luminescence spectroscopy revealed that this AuI???AuI bonded metallo‐macrocycle exhibited yellow phosphorescence.  相似文献   

6.
The synthesis, isolation and spectroscopic characterization of holmium‐based mixed metal nitride clusterfullerenes HoxSc3?xN@C80 (x=1, 2) are reported. Two isomers of HoxSc3?xN@C80 (x=1, 2) were synthesized by the reactive gas atmosphere method and isolated by multistep recycling HPLC. The isomeric structures of HoxSc3?xN@C80 (x=1, 2) were characterized by laser‐desorption time‐of‐flight (LD‐TOF) mass spectrometry and UV/Vis/NIR, FTIR and Raman spectroscopy. A comparative study of MxSc3?xN@C80 (M=Gd, Dy, Lu, Ho) demonstrates the dependence of their electronic and vibrational properties on the encaged metal. Despite the distinct perturbation induced by 4f10 electrons, we report the first paramagnetic 13C NMR study on HoxSc3?xN@C80 (I; x=1, 2) and confirm Ih‐symmetric cage structure. A 45Sc NMR study on HoSc2N@C80 (I, II) revealed a temperature‐dependent chemical shift in the temperature range of 268–308 K.  相似文献   

7.
1,1′‐Ferrocenedithiol reacts with di(4‐methoxyphenyl)silane, diphenylsilane, and di(4‐fluorophenyl)silane in the presence of RhCl(PPh3)3 catalyst to give mixtures of 2,2‐diaryl‐1,3‐dithia‐2‐sila[3]ferrocenophanes (1a–3a) and ? (Fc? S? SiAr2? S) n? (Fc = 1,1′‐ferrocenylene; 1b: Ar = C6H4OMe‐4; 2b: Ar = Ph; 3b: Ar = C6H4F‐4). The products are isolated and characterized by NMR spectroscopy and elemental analyses. The polymers 1b–3b, obtained from a toluene‐soluble fraction of the products, show GPC elution patterns corresponding to Mn values of 2700–4600 (polystyrene standards). The UV–vis spectra of the ferrocenophanes and polymers exhibit a d–d transition peak at about 440 nm, while the polymers show a ππ* transition peak at 320–330 nm. The cyclic voltammograms of 3a (Ar = C6H4F ? 4) and 3b show a reversible redox of the iron center at 0.27 V and 0.35 V (Ag+/Ag) respectively. Reaction of 1,1′‐ferrocenedimethanol with diphenylsilane in the presence of RuCl2(PPh3)3 catalyst results in selective formation of 3,3‐diphenyl‐2,4‐dioxa‐3‐sila[5]ferrocenophane ( 4 ), whose structure was determined by X‐ray crystallography. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

8.
The stoichiometric iron nitrides γ′‐Fe4N, ε‐Fe3N and ζ‐Fe2N were characterized by Mössbauer spectroscopy. The thermal decomposition of ε‐Fe3N was studied in‐situ by means of a specially developed Mössbauer furnace. We found ε‐Fe3N to γ′‐Fe4N and ε‐Fe3Nx (x ≥ 1.3) as decomposition products and determined the border of γ′/ε transformation at T ? 930 K. Mössbauer spectroscopy was applied to study in‐situ the thermal decomposition of the nitridometalate Li3[FeIIIN2] and the formation of Li2[(Li1‐xFeIx)N], the compound with the largest local magnetic field ever observed in an iron containing material. The kinetics of formation and the stability of Li2[(Li1‐xFeIx)N] was of particular interest in the present study.  相似文献   

9.
Five cationic complexes of the general formula [Cp′2Ti(A)2]2+ [Cl?]2 [Cp′ = η5‐(CH3)C5H4 and A = glycine, 1 ; 2‐methylalanine, 2 ; N‐methylglycine, 3 ; L ‐alanine, 4 ; and D ‐alanine 5 ] were prepared by the reaction of Cp′2TiCl2 and the appropriate α‐amino acid in 1:2 molar ratio from methanol–water solution in high yield. Air‐stable crystalline solids, highly soluble in water, were characterized by means of elemental analysis, IR, Raman, 1H, 13C and 14N NMR spectroscopy. The structure of compound 3 was determined by single crystal X‐ray crystallography: orthorhombic Pbca No. 61, a = 9.5310(3), b = 18.2980(5), c = 26.6350(5) Å, V = 4654 Å3, Z = 8. Hydrolytic stability of all compounds in D2O was investigated using 1H NMR spectroscopy within the pD interval of 2.9–6.5. All compounds slowly decomposed during 24 h at pD = 2.94, forming a mixture of hydrolytic products [Cp′2Ti(A)(D2O)]2+, [Cp′2Ti(D2O)2]2+ and respective α‐amino acids. By elevating pD to 4.0 and up to 6.5, a yellowish precipitate was formed, which indicates decomposition of the complexes. These compounds were characterized using elemental analyses, IR and Raman spectroscopy and attributed to oligomeric and/or polymeric structures described empirically by the formula Ti(Cp′)xOy(OH)z (x = 0.65; y = 0.3, z = 1.9). Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

10.
Novel ternary phases, (Pd1?xZnx)18(Zn1?yAly)86?δ (0≤x≤0.162, 0.056≤y≤0.088, 0≤δ≤4), which adopt a superstructure of the γ‐brass type (called γ′‐brass), have been synthesized from the elements at 1120 K. Single‐crystal X‐ray structural analysis reveals a phase width (F$\bar 4$ 3m, a=18.0700(3)–18.1600(2) Å, Pearson symbols cF400–cF416), which is associated with structural disorder based on both vacancies as well as mixed site occupancies. These structures are constructed of four independent 26‐atom γ‐clusters per primitive unit cells and centered at the four special positions A (0, 0, 0), B (1/4, 1/4, 1/4), C (1/2, 1/2, 1/2) and D (3/4, 3/4, 3/4). Two of these, centered at B and C , are completely ordered Pd4Zn22 clusters, whereas the other two, centered at A and D , contain all structural disorder in the system. According to our single‐crystal X‐ray results, Al substitutions are restricted to the A ‐ and D ‐centered clusters. Moreover, the outer tetrahedron (OT) site of the 26‐atom cluster at D is completely vacant at the Al‐rich boundary of these phases. Electronic structure calculations, using the tight‐binding linear muffin‐tin orbital atomic‐spheres approximation (TB‐LMTO‐ASA) method, on models of these new, ternary γ′‐brass phases indicate that the observed chemical compositions and atomic distributions lead to the presence of a pseudogap at the Fermi level in the electronic density of states curves, which is consistent with the Hume‐Rothery interpretation of γ‐brasses, in general.  相似文献   

11.
The title dimeric complex, bis{μ‐2,2′‐[hexane‐1,6‐diyl­bis(nitrilo­methyl­idyne)]­diphenolato‐1:2κ4O,N:N′,O′}dicopper(II),[Cu2(C20H22N2O2)2], has been investigated by single‐crystal X‐ray diffraction, by thermogravimetric analysis and differential scanning calorimetry, and also by FT–IR spectroscopy. Different synthetic and crystallization procedures gave crystals which were quite different in appearance, and it was initially thought that these were different polymorphic forms. Subsequent structure determination showed, in fact, serendipitous preparation of crystals in the P41 space group by one method and in space group P43 by the other. In these enantiomorphic structures, the Cu atoms have a distorted flattened tetrahedral coordination, with Cu—N and Cu—O distances in the ranges 1.954 (4)–1.983 (4) and 1.887 (4)–1.903 (4) Å, respectively.  相似文献   

12.
Preparation and Characterization of Iodoplatinates MexNH4–xPtI4 (x = 2–4), Mixed Valence Octaiododiplatinates(II,IV) with Pt2I8 Groups Iodoplatinates APtI4 (A = MexNH4–x with x = 2–4) have been prepared by partial oxidation of the correspondent hexaiododiplatinates(II) A2Pt2I6 with I2 in methanolic solutions. X-ray structure analyses of the bronze-coloured needle-shaped crystals of the compounds showed rows of dinuclear anions Pt2I82?, built up by edgesharing planar PtI4 groups with PtII und octahedral PtI6 groups with PtIV. The different space requirement of the cations leads to the formation of three different structures. Within the anion stacks weak intermolecular PtIV? I …? PtII interactions are detectable by Raman spectroscopy.  相似文献   

13.
Assembly of copper(I) halide with a new tripodal ligand, benzene‐1,3,5‐triyl triisonicotinate (BTTP4), afforded two porous metal–organic frameworks, [Cu2I2(BTTP4)]?2 CH3CN ( 1? 2 CH3CN) and [CuBr(BTTP4)]?(CH3CN ? CHCl3 ? H2O) ( 2? solvents), which have been characterized by IR spectroscopy, thermogravimetry (TG), single‐crystal, and powder X‐ray diffraction (PXRD) methods. Compound 1.CH3CN is a polycatenated 3D framework that consists of 2D (6,3) networks through inclined catenation, whereas 2 is a doubly interpenetrated 3D framework possessing the ThSi2‐type ( ths ) (10,3)‐b topology. Both frameworks contain 1D channels of effective sizes 9×12 and 10×10 Å2, which amounts to 43 and 40 % space volume accessible for solvent molecules, respectively. The TG and variable‐temperature PXRD studies indicated that the frameworks can be completely evacuated while retaining the permanent porosity, which was further verified by measurement of the desolvated complex [Cu2I2(BTTP4)] ( 1′ ). The subsequent guest‐exchange study on the solvent‐free framework revealed that various solvent molecules can be adsorbed through a single‐crystal‐to‐single‐crystal manner, thus giving rise to the guest‐captured structures [Cu2I2(BTTP4)]?C6H6 ( 1.benzene ), [Cu2I2(BTTP4)]?2 C7H8 ( 1.2toluene ), and [Cu2I2(BTTP4)]?2 C8H10 ( 1.2ethyl benzene ). The gas‐adsorption investigation disclosed that two kinds of frameworks exhibited comparable CO2 storage capacity (86–111 mL g?1 at 1 atm) but nearly none for N2 and H2, thereby implying its separation ability of CO2 over N2 and H2. The vapor‐adsorption study revealed the preferential inclusion of aromatic guests over nonaromatic solvents by the empty framework, which is indicative of selectivity toward benzene over cyclohexane.  相似文献   

14.
Reaction of O,O′‐diisopropylthiophosphoric acid isothiocyanate (iPrO)2P(S)NCS with 1,10‐diaza‐18‐crown‐6, 1,7‐diaza‐18‐crown‐6, or 1,7‐diaza‐15‐crown‐5 leads to the N‐thiophosphorylated bis‐thioureas N,N′‐bis[C(S)NHP(S)(OiPr)2]‐1,10‐diaza‐18‐crown‐6 ( H2LI ), N,N′‐bis[C(S)NHP(S)(OiPr)2]‐1,7‐diaza‐18‐crown‐6 ( H2LII ) and N,N′‐bis[C(S)NHP(S)(OiPr)2]‐1,7‐diaza‐15‐crown‐5 ( H2LIII ). Reaction of the potassium salts of H2LI–III with a mixture of CuI and 2,2′‐bipyridine ( bpy ) or 1,10‐phenanthroline ( phen ) in aqueous EtOH/CH2Cl2 leads to the dinuclear complexes [Cu2(bpy)2LI–III] and [Cu2(phen)2LI–III] . The structures of these compounds were investigated by 1H, 31P{1H} NMR spectroscopy, and elemental analysis. The crystal structures of H2LI and [Cu2(phen)2LI] were determined by single‐crystal X‐ray diffraction. Extraction capacities of the obtained compounds in comparison to the related compounds 1,10‐diaza‐18‐crown‐6, N,N′‐bis[C(=CMe2)CH2P(O)(OiPr)2]‐1,10‐diaza‐18‐crown‐6, N,N′‐bis[C(S)NHP(O)(OiPr)2]‐1,10‐diaza‐18‐crown‐6 towards the picrate salts LiPic, NaPic, KPic. and NH4Pic were also studied.  相似文献   

15.
Three‐ and five‐membered rings that bear the (Si‐C‐S ) and (Si‐C‐C‐C‐S ) unit have been synthesized by the reactions of L SiCl ( 1 ; L =PhC(NtBu)2) and L′ Si ( 2 ; L′ =CH{(C?CH2)(CMe)(2,6‐iPr2C6H3N)2}) with the thioketone 4,4′‐bis(dimethylamino)thiobenzophenone. Treatment of 4,4′‐bis(dimethylamino)thiobenzophenone with L SiCl at room temperature furnished the [1+2]‐cycloaddition product silathiacyclopropane 3 . However, reaction of 4,4′‐bis(dimethylamino)thiobenzophenone with L′ Si at low temperature afforded a [1+4]‐cycloaddition to yield the five‐membered ring product 4 . Compounds 3 and 4 were characterized by NMR spectroscopy, EIMS, and elemental analysis. The molecular structures of 3 and 4 were unambiguously established by single‐crystal X‐ray structural analysis. The room‐temperature reaction of 4,4′‐bis(dimethylamino)thiobenzophenone with L′ Si resulted in products 4 and 5 , in which 4 is the dearomatized product and 5 is formed under the 1,3‐migration of a hydrogen atom from the aromatic phenyl ring to the carbon atom of the C? S unit. Furthermore, the optimized structures of probable products were investigated by using DFT calculations.  相似文献   

16.
Three new coordination compounds, [Pb(HBDC‐I4)2(DMF)4]( 1 ) and [M(BDC‐I4)(MeOH)2(DMF)2]n (M = ZnII for 2 and MnII for ( 3 ) (H2BDC‐I4 = 2, 3, 5, 6‐tetraiodo‐1, 4‐benzenedicarboxylic acid), were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric (TG) analysis, and X‐ray single crystal structure analysis. Single‐crystal X‐ray diffraction reveals that 1 crystallizes in the monoclinic space group C2/c and has a discrete mononuclear structure, which is further assembled to form a two‐dimensional (2D) layer through intermolecular O–H ··· O and C–H ··· O hydrogen bonding interactions. The isostructural compounds 2 and 3 crystallize in the space group P21/c and have similar one‐dimensional (1D) chain structures that are extended into three‐dimensional (3D) supramolecular networks by interchain C–H ··· π interactions. The PbII and ZnII complexes 1 and 2 display similar emissions at 472 nm in the solid state, which essentially are intraligand transitions.  相似文献   

17.
We have synthesized ciprofloxacin‐based metal complexes of bipyridine derivatives [Cu(CFL)(An)Cl].2H2O (where CFL = ciprofloxacin and A = bipyridines e.g. A1 = 4‐(4‐fluorophenyl)‐6‐p‐tolyl‐2,2′‐bipyridine, A6 = 4‐(4‐(benzyloxy)phenyl)‐6‐(4‐bromophenyl)‐2,2′‐bipyridine, etc.). The ligands and complexes were characterized using analytical (C, H, N elemental analysis, TGA and magnetic measurement) and spectroscopic methods (1H and 13C NMR, FT‐IR, fast atom bombardment mass and reflectance spectroscopy). The products were evaluated by screening for DNA interaction activity on herring sperm DNA and studies suggest intercalative mode of DNA binding. The antimicrobial activity was determined in terms of minimum inhibitory concentration. Superoxide dismutase mimic studies were performed using the NADH/PMS/NBT system. The brine shrimp bioassay was also carried out to study the in vitro cytotoxic properties of the synthesized metal complexes. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   

18.
In this work, by using two kinds of viologen ligands three POM-based Compounds were obtained under hydrothermal conditions, namely [AgI(bmypd)0.5(β-Mo8O26)0.5] (1) (bmypd ⋅ 2Cl=1,1′-[Biphenyl-4,4′-bis(methylene)]bis(4,4′-bipyridyinium)dichloride), [AgI2(bypy)4(HSiW12O40)2] ⋅ 14H2O (2) and [AgI(bypy)(γ-Mo8O26)0.5] (3) (bypy⋅Cl=1-Benzyl-4,4′-bipyridyinium chloride). The structures were characterized by Fourier transform infrared spectroscopy (FT–IR), Powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS) and single crystal X-ray diffraction. Compounds 1–3 show excellent photochromic ability with fast photoresponse under the irradiation of ultraviolet light with different degrees of color changes. So compounds 1–3 can be used as visible ultraviolet detectors. Compounds 1–3 also possess photoluminescence properties with fast and excellent fluorescence quenching effect. Compounds 1–3 also can be used as inkless and erasable printing materials with suspensions of 1–3 applied to filter paper. Compounds 1–3 can also produce color changes in amine vapor environment, especially in an NH3 atmosphere. Compounds 1–3 can be used as organic amine detectors.  相似文献   

19.
The title compound, rac‐6,13‐dihydro‐6,13‐methanopentacene ( 1 ), has been synthesized and characterized by elemental analysis, FT‐IR, 1H NMR, UV‐Vis, HRMS spectra, cyclic voltammetry and single‐crystal X‐ray diffraction. The crystal belongs to orthorhombic, space group P212121, with Z = 4 and cell dimensions a = 6.0185(4), b = 8.1914(6), c = 31.4080(19) Å. In the crystal structure, two types of intermolecular C–H···π hydrogen bonds are observed, and further stabilize the crystal structure. Its photophysical and electrochemical properties and complementary density functional theory (DFT) calculations are reported.  相似文献   

20.
A double azido‐bridged CuII dinuclear complex with the chelating chiral ligand, [Cu2(L)2(N3)4] ( 1 ) [L = (+)‐2, 2′‐isopropylidene‐bis((4R)‐4‐benzyl‐2‐oxazoline)] was synthesized and characterized by single‐crystal X‐ray diffraction, IR spectroscopy, magnetic measurements, and theoretical studies. The asymmetric double end‐on azido bridges in complex 1 lead to a weak antiferromagnetic behavior with J = –7.4 cm–1. The exchange interactions in complex 1 were investigated by DFT calculations, and the calculated exchange interaction (J = –8.0 cm–1) is in good agreement with the experimental value.  相似文献   

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