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1.
This paper discloses two new side-chain metallopolymers containing an unsymmetrical organometallic Schiff base complex of Ni(II) linked to a polymethylmethacrylate (PMMA) matrix. The neutral ferrocene substituted Schiff base complex 1, Ni{CpFe(η5-C5H4)-C(O)CH=C(CH3)N–o-C6H4N=CH-(2-O,5-OH-C6H3)} where (Cp = η5-C5H5), was synthesized via template reaction by condensation of the tridentate half-unit metalloligand Fc-C(O)CH=C(CH3)-N(H)-o-C6H4NH2 (Fc = ferrocenyl = CpFe(η5-C5H4)) with 2,5-dihydroxybenzaldehyde in the presence of nickel(II) acetate tetrahydrate. The binuclear Schiff base complex of Ni(II) containing an aromatic free hydroxyl group was reacted under basic conditions with PMMA to afford, upon trans-esterification reaction, metallopolymers 2 (complex 1 monomeric unit/PMMA = 1/5) and 3 (complex 1 monomeric unit/PMMA = 1/3). Elemental analysis, FT-IR, 1H and 13C NMR spectroscopies, and cyclic voltammetry were utilized to characterize the newly synthetized compounds. Surface morphology of the metallopolymer film of 2 was studied using atomic force microscopy.  相似文献   

2.
An axial substitution of the coordinated acetonitrile molecules in dinuclear Cu(I) compound, [Cu2(μ-PhPPy2)2(CH3CN)2](ClO4)2 (1) (PhPPy2 = bis(2-pyridyl)phenylphosphine) by various dicarboxylates (isophthalate, terephthalate and naphthalene-2,6-dicarboxylate) led to a class of new linear coordination polymers, {[Cu2(μ-PhPPy2)2](μ-1,3-C6H4(CO2)2)} (2), {[Cu2(μ-PhPPy2)2](μ-1,4-C6H4(CO2)2)} (3) and {[Cu2(μ-PhPPy2)2](μ-2,6-C12H6(CO2)2)} (4). X-ray crystallographic studies reveals that all the polymers adopt almost linear structures, where the dicarboxylate groups connect dinuclear Cu(I) units as linkers. In 2 and 4, polymeric chains are parallel to each other. However the chains in 3 are arranged layer by layer, where polymeric chains are parallel in one layer, but chains in the neighboring layers are aligned with the angle (42°). The detailed structural analyses demonstrate that in solid state, the polymeric chains display different orientations which are controlled by interchain π–π and CH–π interactions. In solid state, all the coordination polymers are highly emissive at room temperature, which exhibit phosphorescence characteristics and are assigned as metal to ligand charge transfer.  相似文献   

3.
The dimeric complex of Cu(I) [Cu2(PPh3)4(MeCN)2(Bpy)](BF4)2 (1a, Bpy = 4,4′-dipyridyl) self-assembles in CH2Cl2 or acetone and shows intense photoluminescence (excitation λmax = 356 nm, emission λmax = 486 nm, ? = 0.47). The MeCN ligands are readily removed from 1a, producing [Cu2(PPh3)4(Bpy)](BF4)2 (1b) and altering the photophysical behavior (excitation λmax = 336 nm, emission λmax = 568 nm, ? = 0.07). The desolvated compound 1b reversibly absorbs many vapor phase nucleophiles, as revealed by thermogravimetry. Intense luminescence emission is restored for 1b/Nu, Nu = MeCN (1a), acetone, tetrahydrothiophene (THT), and Et2S. Films of 1b are produced when CH2Cl2 solutions of 1a are cast onto glass. The films also react with Nu vapor, again producing intense emission. The pyrazine-bridged dimer [Cu2(PPh3)4(MeCN)2(Pyz)](BF4)2 (2a) is produced in CH2Cl2, while [Cu2(PPh3)4(MeCN)(acetone)(Pyz)](BF4)2?½[Cu2(PPh3)4(MeCN)2(Pyz)](BF4)2 (2b) is formed in acetone. The crystal structure of the polymer {[Cu(PPh3)2(Bpy)](BF4)?acetone} n (3) is reported, as is the mixed polymer/dimer structure {[Cu(PPh3)2(Pyz)](BF4)} n n[Cu2(PPh3)4(BF4)2(Pyz)] (4b) in which the dimer units show Cu–FBF3 coordination. The Pyz dimer and the Pyz and Bpy polymers show much weaker luminescence behavior than that of Bpy dimers 1a and the related 1b/Nu adducts. Nucleophile adduct structures [Cu2(PPh3)4(THT)2(Bpy)](BF4)2?½ethyl ether (5) and [Cu2(PPh3)4(Py)2(Bpy)](BF4)2?CH2Cl2 (6) confirmed the coordination of one Nu per Cu to 1b.  相似文献   

4.
The reactions of phosphorus ylides of the type Ph3P=C(H)C(O)R [R = 2,4-dichlorophenyl (L 1 ) and 4-isopropylphenyl (L 2 )] with HgX2 [X = Cl (1, 4), Br (2, 5) and I (3, 6)] salts using methanol as a solvent are reported. Single crystal X-ray analysis carried out on L 1 , 2 and 3 and reveals the presence of a novel polymeric structure for 2 and a centrosymmeteric dimeric structure for 3. The complexes have been studied by elemental analyses, IR, 1H and 31P NMR spectroscopy. On the basis of DFT calculations, the formation of [Hg2Br6]2? anions in 2 has a key role in the formation of the polymeric structure; and, the formation of [Hg2L2I4] molecule thermodynamically is about 25 kcal/mol more favorable than the corresponding [Hg2L2Br4] molecule.  相似文献   

5.
Two discrete salen type homo-multinuclear Yb3 and Yb4 complexes, namely, [Yb3L3(OAc)3]·3CH3OH·H2O (1) and [Yb4L2(OAc)43-OH)2(H2O)2](ZnCl4)·3CH3OH (2) (H2L = N,N′-bis(2-oxy-3-methoxybenzylidene)-1,2-phenylenediamine) have been synthesized by reactions of H2L and different ytterbium salts. X-ray crystallographic analysis reveals that complex 1 exhibits a triple-decker Yb3 sandwich structure with a ratio of H2L:Yb = 1:1, while complex 2 exhibits a defect-dicubane Yb4 core with a ratio of H2L:Yb = 1:2. The NIR luminescence of complexes 1 and 2 have been investigated and discussed.  相似文献   

6.
The synthesis and structural characterization of four novel triorganotin(IV) complexes, {(R3Sn)2[C2H4S(COO)2]} n (R = Me: 1), {(R3Sn)4[C2H4S(COO)2]2} n (R = nBu: 2), {(R3Sn)2[C4H8S(COO)2]} n (R = Me: 3; nBu: 4) were obtained by the reaction of 2,2′-thiodiglycolic acid, 3,3′-thiodipropionic acid and the corresponding R3SnCl (R = Me, nBu) with potassium hydroxide in methanol. All the complexes were characterized by elemental analysis, Fourier transform infrared and nuclear magnetic resonance (1H, 13C, 119Sn) spectroscopies, X-ray crystallography and thermogravimetric analyses. The crystal structures show that 1 has 2D network structure in which 2,2′-thiodiglycolic acid acts as a tetradentate ligand coordinating to the trimethyltin(IV) ions. Complexes 2, 3, and 4 are 3D metal-organic framework structures in which the deprotoned acids act as a tetradentate ligand afforded by four oxygen atoms.  相似文献   

7.
A series of piano-stool complexes of the cymantrene family (cymantrene = Mn(η5-C5H5)(CO)3, 1) undergoes facile replacement of a carbonyl ligand by P(OPh)3 when oxidized by one-electron in CH2Cl2/[NBu4][B(C6F5)4]. Data on the previously characterized complexes 1, Mn(η5-C5H4NH2)(CO)3 (3) and Mn(η5-C5Me5)(CO)3 (6) have been supplemented by cyclic voltammetry (CV) and IR spectroscopy on Mn(η5-C5H4Me)(CO)3 (2), Mn(η5-C5H4I)(CO)3 (4), and Mn(η5-C5H4C(O)H)(CO)3 (5). The substitution rates, determined by digital simulations of CV scans, ranged from 4 M?1 s?1 for 6 + to 3 × 105 M?1 s?1 for 5 +. In general, a more strongly donating cyclopentadienyl substituent slows down the CO substitution rate. For mono-cyclopentadienyl substituted complexes, the logarithm of ksub is shown to increase linearly with either the weighted average of the CO stretching frequencies or the E1/2 value of the redox process. An exception to this generalization is the amine-substituted complex 3, for which the CO-substitution rate is higher than predicted by its E1/2 potential. The substitution rate of the pentamethylated Cp complex 6 + is slowed by about an order of magnitude owing to steric effects. The efficacy of this method to predict the CO-substitution rate of a cymantrene-tagged molecule was tested with a cymamtrene-derivatized diarylethene complex, 7. The measured P(OPh)3-for-CO substitution rate of 3.7 × 102 M?1 s?1 for 7 + was very close to that predicted by the E1/2 value of 7. A ligand electronic parameter, EL, of 0.62 was determined for the triphenylphosphite ligand. These studies build on the previous CO substitution-rate analyses by Sweigart and others.  相似文献   

8.
Two new cadmium thiolato-carboxylate complexes, [Cd2(mba)2(2,2′-bpy)2] (1), [Cd2(dtba)2(2,2′-bpy)4]·4H2O (2) (H2mba = 2-mercaptobenzoic acid, H2dtba = 2,2′-dithiodibenzoic acid, 2,2′-bpy = 2,2′-bipyridine) were obtained by reacting Cd(II) salts and the ligands of H2mba and 2,2′-bpy, and were characterized by the single-crystal X-ray diffraction, IR, 2D-COS IR, solid UV, TG and XRD. In complex 2, the H2dtba ligand came from the in situ S–S function reaction of H2mba under the hydrothermal conditions. Complexes 1 and 2 are both 1D chains, but the difference lies in the linkage of the ligands. The 3D super-molecular frameworks of 1 and 2 are produced by ππ stacking interaction between the 2,2′-bpy ligands and the hydrogen bonds of O–H…O with ths-type and dia-type topology, respectively. The fluorescent emissions are observed in 1 and 2 with λ em = 533 nm and λ em = 436 nm, due to the ligand-to-metal charge transfer (LMCT) and π* → π transitions, respectively.  相似文献   

9.
The [(η5-C5H4(CH2)3N3)Mo(CO)3]2 dimer (3) was prepared and used to determine if the Huisgen cycloaddition reaction could be used to synthesize high molecular weight star polymers with metal–metal bonds in the arms. Several different click catalysts were examined. Cp*Ru(PPh3)2Cl (Cp* = η5-C5(CH3)5) was previously shown to catalyze the formation of metal–metal bond-containing polymers using click chemistry; however, this catalyst underwent a Staudinger reaction with dimer 3 when a model coupling reaction was attempted with phenylacetylene. In order to avoid the Staudinger reaction, Cp*Ru(COD)Cl was used as the catalyst in the reaction of 3 with phenylacetylene, and coupling was observed after 14 h. Synthesis of a star polymer was attempted with 3 and 1,3,5-triethynylbenzene. Instead of coupling, Cp*Ru(COD)Cl reacted with the 1,3,5-triethynylbenzene. A third catalyst, Cu(IMes)Cl (IMes = 1,3-dimesityl-imidazol-2-ylidene) was used to couple 3 with 1,3,5-triethynylbenzene in 48 h. Both a high molecular weight polymer (M n  = 77,000 g mol?1) and a tripodal star core (M n  = 1,800 g mol?1) were successfully prepared with this catalyst.  相似文献   

10.
This article reviews the surface adsorption of p-benzoquinonemonoimine zwitterions from the class of N-alkyldiaminoresorcinones (or 4,6-bis-dialkylaminobenzene-1,3-diones, i.e. C6H2(···NHR)2(···O)2), where R = H, R = C2H5, n-C4H9), on a variety of conducting surfaces. These small molecules with a large electrical dipole exhibit molecular orientation and packing on surfaces depending on the deposition methodology (from solution or from the vapor) as well as the substrate. What is very clear from the investigations of this class of molecules is that inter-molecular interaction is not simply driven by dipolar interactions alone, but frontier orbital symmetry as well. This is illustrated by the reversible adsorption of di-iodobenzene on molecular films of (6Z)-4-(butylamino)-6-(butyliminio)-3-oxocyclohexa-1,4-dien-1-olate C6H2(···NHR)2(···O)2 where R = n-C4H9, where it is clear that absorption is isomer specific.  相似文献   

11.
Novel oxo-centered, acetate-bridged trinuclear ruthenium clusters functionalized with two pyridine ligands with thienyl substituents, [Ru3O(CH3COO)6(CO)(L1)2] (1) and [Ru3O(CH3COO)6(CO)(L2)2] (2), where L1 = 4-(2-thienyl)pyridine and L2 = 4-(2,2′-bithienyl)pyridine, have been synthesized and characterized. The molecular structure of 2 has been determined by single-crystal X-ray diffraction. One-electron oxidation of 2 with silver(I) cation has led to the isolation of a CO-dissociated product, [Ru3O(CH3COO)6(H2O)(L2)2]PF6 (3·PF 6 ), and subsequent reaction with 4-dimethylaminopyridine (dmap) gave [Ru3O(CH3COO)6(dmap)(L2)2]PF6 (4·PF 6 ). Linear metallopolymers containing the {Ru3O(CH3COO)6} groups have been deposited onto indium-tin oxide surface via oxidative electropolymerization of 2, 3·PF 6 , and 4·PF 6 . These metallopolymer thin films exhibit three-color electrochromism in the UV/Vis and near-IR region associated with the Ru3 II,III,III, Ru3 III,III,III, and Ru3 III,III,IV oxidation states.  相似文献   

12.
Two types of lanthanide thiolato-carboxylate complexes, [Type I: [Yb(dtba) (Hdtba)] n (1), Type II: [Ln(dtba)1.5(biim)] n (Ln = Pr (2a), Nd (2b), Sm (2c), Eu (2d), Gd (2e), Tb (2f), Dy (2g), H2dtba = 2,2′-dithiodibenzoic acid, bimm = diimidazole)] have been obtained by hydrothermal method and characterized by the single-crystal X-ray diffraction, IR, 2D-COS IR, TG and the luminescence analysis. The H2dtba ligand came from the in situ S–S function reaction of 2-mercaptobenzoic acid (H2mba) under the hydrothermal condition. Complex 1 is a 2D bamboo-like sqr-topology layered structure, and the 3D (4, 4, 6)-connected supramolecular frameworks is produced by the hydrogen bonds of O–H···O. Complexes of type II (from 2a to 2g) are isostructural and they are assigned to 1D rope-like chains by introducing the chelating ligand of diimidazole. These 1D rope-like chains are further linked by N–H···O hydrogen bonds into a 3D supramolecular framework with CdSO4-type topology. Photoluminescence studies reveal that complexes 2b, 2c, 2d, 2f, 2g exhibit strong lanthanide characteristic emission bands in the solid state at room temperature.  相似文献   

13.
Four N,N′-bis(salicylidene)-1,2-(phenylene-ediamine) (H2L) trinuclear lanthanide complexes, namely, [Ln3L3(CH3OH)2(NO3)3]·(CH2Cl2)·(CH3OH)·(H2O)2 [Ln = Tb (1), Ho (2), Er (3) and Lu (4)], have been isolated by the reactions of H2L and Ln(NO3)3·6H2O. And one N,N′-bis(salicylidene)-1,2-(phenylene-ediamine) dinuclear neodymium complex [Nd2L3(CH3OH)] (5) has been harvested from the reaction of H2L with Nd(OAc)3·4H2O. X-ray crystallographic analysis reveals that complexes 1?4 are of triple-decker trinuclear sandwich structure, while complex 5 is of a triple-decker dinuclear sandwich structure, expanding upon the recent reports of the multinuclear pure lanthanide complexes.  相似文献   

14.
The reaction of two η5-cyclopentadienyliron(II)-functionalized terephthalate and phthalate metalloligands, namely [(η5-C5H5)FeII6-1,4-HO2CC6H4CO2H)][(η5-C5H5)FeII6-1,4-HO2CC6H4CO2)][PF6] and [(η5-C5H5)FeII6-1,2-HO2CC6H4CO2H)][(η5-C5H5)FeII6-1,2-HO2CC6H4CO2)][PF6]—hereafter [H2 CpFeTP][HCpFeTP][PF6] and [H2 CpFeP][HCpFeP][PF6], respectively—with [UO2(NO3)2]·6H2O under hydrothermal conditions yielded four new coordination polymers; (1) [(UO2)F(HCpFeTP)(PO4H2)]·2H2O, (2) [(UO2)2(CpFeTP)4]·5H2O, (3) [(UO2)2F3(H2O)(CpFeP)], and (4) [H2 CpFeP][UO2F3]. The use of metalloligands has proven to be a viable route towards the incorporation of a secondary metal center into uranyl bearing materials. Depending upon the protonation state, the iron sandwich metalloligands may vary from zwitterionic neutral or monoanionic coordinating species as observed in compounds 13, or a positively charged species that hydrogen bonds with anionic [UO2F3]? chains as observed in 4. Further, the hydrolysis of the charge balancing PF6 ? anion increases the diversity of UO2 2+ coordinating species by contributing both F? and PO4 3? anions (1, 3, 4). The luminescent properties of 14 were also studied and revealed the absence of uranyl emission, suggestive of a possible energy transfer from the uranyl cation to the iron(II) metal center.  相似文献   

15.
A new luminescent Zn(II) compound, [Zn2(IN)3(bpy)0.5(CH3COO)]·2(DMA) (1, IN = isonicotinate, bpy = 4,4′-bipyridine, DMA = N,N-dimethylacetamide), was synthesized under solvothermal condition and structurally characterized by single crystal X-ray diffraction. Compound 1 features a (3,4)-connected bilayer structure with honeycomb-like 63 layers and bpy pillars. Each individual bilayer is catenated with two adjacent bilayers, giving rise to a rare 2D + 2D → 3D polycatenation motif.  相似文献   

16.
A novel bimetallic 4d-4f complex, [ErIII(DMF)4(H2O)2][MoV(CN)8i-C3H7OH·4H2O (1) (DMF = N,N′-dimethylformamide), has been synthesized and structurally characterized. The crystalline analysis shows that the build up of 1D zigzag-like chains produces complex 1, which is the first structurally characterized example of 1D structure based on the [Mo(CN)8]3? and Er3+ ions as building blocks. Complex 1 crystallizes in monoclinic system of space group P21/n, with a = 12.031(6), b = 16.027(7), c = 20.263(9) Å, β = 105.711(6)º and Z = 4. Magnetic measurements confirm that 1 presents probably a ferromagnetic interaction between the MoV and ErIII ions.  相似文献   

17.
Three new coordination polymers, namely, {[Cd(H2bptc)(IP)(H2O)]·2H2O} n (1), {[Mn2(IP)2(dstc)]·6H2O} n (2) and {[Zn2(IP)2(dstc)]·3H2O} n (3) (IP = 1H-imidazo[4,5-f][1,10]-phenanthroline, H4bptc = 3,3′,4,4′-benzophenonetetracarboxylic acid, and H4dstc = 3,3′,4,4′-diphenylsulfonetetracarboxylic acid) have rationally designed and characterized by single crystal X-ray diffraction. Polymer 1 shows a 1D ribbon-like structure. Although compounds 2 and 3 feature 2D grid networks, the coordinative modes of dstc ligand and the arrangements of IP ligand are very different. Furthermore, the luminescence properties for 1 and 3, as well as the magnetism of 2 are explored in detail.  相似文献   

18.
Two d10 metal-organic coordination polymers, [Cd2(4-cpa)4(bmip)2]n (1) and [Zn(4-cpa)2(4,4′-bpy)]n (2), [4-cpa = 4-chlorophenylacetate, bmip = 1,3-bis(2-methylimidazoly)propane, 4,4′-bpy = 4,4′-bipyridine], were hydrothermally synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis (TGA), powder X-ray diffraction and single-crystal X-ray diffraction. Single-crystal X-ray diffraction studies indicated that both 1 and 2 display analogous wave-like infinite chain structures. The two coordination polymers are further extended into 3D supramolecular structures through π···π stacking interactions and C–H···O hydrogen bonds for 1 and π···π stacking interactions, C–H···π stacking interactions and C–H···O hydrogen bonds for 2. Both 1 and 2 emit the intense blue luminescence at room temperature. The 4-Hcpa ligand and complexes 1 and 2 have been screened for their herbicidal activities against Brassica napus L. and Echinochloa crusgalli L. The results are compared with the activity of quizalofop-P-ethyl. Both compounds exhibit high catalytic properties on degradation of methyl orange in Fenton-like process.  相似文献   

19.
Two new metal–organic frameworks; namely, [Cd2(pam)2(bpe)1.5(DMF)2(H2O)] n ·2n(DMF) (1) and [Cd(pam)(bix)] n (2) (H2pam = pamoic acid, bpe = 1,2-di(4-pyridyl)ethylene, bix = 4,4′-bis(imidazol-1-ylmethyl)benzene, DMF = N,N′-dimethylformamide), were solvothermally synthesized via varying the auxiliary ligand. Single crystal X-ray diffraction analysis reveals that compound 1 shows a 2D→3D polythreaded motif based on (3,4)-connected 2D sheets, while compound 2 features a 4-connected sql tetragonal plane net, which further extended into a 3D supramolecular framework through intermolecular CH···π interactions. In addition, the luminescent and thermal stabilities properties of these two compounds were investigated.  相似文献   

20.
A new coordination polymer [Cd3(btc)2(e-urea)4].(e-urea)2 (1; btc = 1,3,5-benzenetricarboxylate; e-urea = ethyleneurea) has been urothermally synthesized using ethyleneurea hemihydrate as the solvent and exhibits (3,6)-connected rutile (rtl) topology. The structure of 1 consists of trinuclear Cd units and the btc linkers. Species 1 features a non-interpenetrating three-dimensional open framework with channels filled by the e-urea additives and guest molecules. The thermogravimetric behavior and photoluminescent property of 1 were studied.  相似文献   

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