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1.
An efficient method was developed for the preparation of three tetraorganodistannoxane complexes, (C2H5)8Sn4Cl2(CH3O)2O2 (1), (CH3)8Sn4(C3H4N3S)2(CH3O)2O2 (2) and (C4H9)8Sn4(C3H4N3S)2(CH3O)2O2 (3). All prepared complexes were characterized by infrared, 1H, 13C and 119Sn NMR spectroscopes and elemental analysis. The molecular structure of a representative complex (1) was determined by single-crystal X-ray diffraction. Results showed that 1 is a tetranuclear, centrosymmetric dimeric, and contains two endo-cyclic five-coordinated tin atoms and two exo-cyclic five-coordinated tin atoms. Compound 1 lies about a center of inversion and the tetranuclear molecule features a three-ring-staircase Sn4O4 core. The asymmetric unit of 1 contains two independent Sn(IV) atoms and a 2D infinite rigid chain structure forms via C–H···Cl interactions between tetranuclear units.  相似文献   

2.
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   

3.
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   

4.
Three novel transition metal coordination polymers, [Ni(C18H16N3O2)2·2CH3OH] n (1), [Zn(C18H16N3O2)2·4CH3OH] n (2) and [Cd(C18H16N3O2)2·2CH3OH] n (3) (C18H16N3O2=2-acetylpyridine-d-tryptophan) were synthesized and characterized by elemental analysis, IR, UV, 1H NMR and X-ray diffraction single crystal analysis. The analyses of the structures indicate that all three materials crystallize in the tetragonal crystal system, space group P41212. They have similar structures; i.e., the Schiff base coordinates in its deprotonated form and behaves as a hexadentate (4N+2O) coordinated ligand to form a distorted octahedron geometry. On the other hand, as a result of the alternate arrangement of chains through N–H···O intermolecular hydrogen bonds interactions, 2-D layers are formed for the three complexes. Furthermore, the luminescent properties and thermal stabilities of the three complexes were investigated.  相似文献   

5.
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   

6.
Two new nano-structured Hg(II) supramolecular complexes, [Hg(5,5′-di-t-but-bpy)(μ-Br)Br]2[Hg(5,5′-di-t-but-bpy)Br2](1) and [Hg(5,5′-di-t-but-bpy)I2] (2) were synthesized by the sonochemical method. The structures of 1 and 2 were characterized by elemental analysis, IR, 1H-NMR, and 13C-NMR spectroscopy and single crystal X-ray diffraction. Their thermal stabilities were studied by thermogravimetric and differential thermal analyses. Solid-state luminescent spectra of 1 and 2 indicate a fluorescent broad emission band between 304 and 404 nm with excitation at 284 nm. These nanostructured coordination polymers were characterized by scanning electron microscopy, elemental analysis, and IR spectroscopy.  相似文献   

7.
Two new Co(II) complexes of 1,4-di(benzimidazole-1-yl)benzene ligand (L) with the formulas [(CoLCl2)(CHCl3)(DMF)] (1) and [CoL(NO3)2] (2) have been synthesized by anion-directed self-assembly. Both complexes have been characterized by elemental analyses, IR, and X-ray single crystal diffraction. Complexes 1 and 2 exhibit 1D chain structures. In 1, Co(II) ions possess a distorted tetrahedral coordination environment composed of N2Cl2 donors from two L ligands and two chloride ions, while the Co(II) ions in 2 reveal a distorted octahedral structure defined by the N2O4 donors from two L ligands and two nitrate anions. These results illustrate that the anions play an important role in the self-assembly of metal–organic materials.  相似文献   

8.
Two novel cobalt(II) complexes [Co(L1)2](BF4)2·CH3CN·0.5H2O (1) and [Co(L2)2](BF4)2 (2) (L1 = 4′-(3,4,5-trimethoxy-phenyl)-[2,2′:6′,2″]terpyridine, L2 = 4′-(3,4,5-tris-hexadecyloxy-phenyl)-[2,2′:6′,2″]terpyridine) have been synthesized, and their structural, magnetic and mesomorphic properties were characterized by single crystal X-ray diffraction (XRD) analysis, temperature-dependent magnetic susceptibility, POM, DSC, and powder XRD analysis. The molecular structure of the complex 1 with short alkyl substituents exhibited that the metal ion has an N6 coordination sphere of distorted octahedral geometry and various intermolecular π–π interactions are important factors influencing the crystalline array. The magnetic behaviour of 1 displayed a typical of gradual spin transition for cobalt(II) terpyridine complexes. On the other hand, the complex 2 possessing linear long alkyl chains showed a gradual spin transition between low-spin and high-spin with a thermal hysteresis loop (T 1/2↑ = 338 and T 1/2↓ = 327 K) triggered by the crystal-to-mesophase transition. The powder XRD and POM analyses were indicative of the liquid crystalline lamellar phase of 2.  相似文献   

9.
The effects of B(C6F5)3 on the activation of the Ni(0) and Ni(II) complexes were studied in the polymerization of norbornene. The Ni(0) complex, such as bis(1,5-cyclooctadiene)nickel (Ni(COD)2 (1), biacetylbis(2,6-diisopropylphenylimmine)(1,3-butadiene)nickel (2), or tetrakis(triphenylphosphine)nickel (5), in combination with B(C6F5)3, was determined to have high activity in the polymerization of norbornene. On the other hand, the Ni(II) complex with B(C6F5)3 did not provide any activity at all under analogous conditions regardless of the structure of the Ni(II) complex. The use of other borane compounds, such as B(C6H5)3, BEt3, and BF3 etherate, with Ni(COD)2 (1) in place of B(C6F5)3 clearly showed the main functions of B(C6F5)3. The high Lewis acidity of B(C6F5)3 enabled it to activate catalytic complexes, thus inducing polymerization. The study of the 1H, 13C, and 19F NMR spectra of the polynorbornene produced with Ni(COD)2 (1) and B(C6F5)3, in the presence or absence of ethylene, showed that the initiation of addition polymerization occurred through the insertion of the exo face of the norbornene into the Ni-C bond of the C6F5 ligand. A new polymerization mechanism was proposed in norbornene polymerization, wherein the active complex formed from Ni(COD)2 (1) and B(C6F5)3 acts as a catalyst.  相似文献   

10.
Organometallic derivatives of the cyclotriphosphazene N3P3[OC6H4CH2CN·TiClCp2]6 (1), N3P3(O6H5)5[OC6H4N·W(CO)5] (2), N3P3[OC6H4CH2CN·Mo(CO)5]6 (3), [N3P3(O6H5)5(OC5H4N·CpRu(PPh3)2)][PF6] (4), [N3P3(O2C12H8)2OC5H4N·Ag(PPh3)][OSO2CF3] (5), N3P3[OC6H5]5 [OC5H4N·Cu][PF6] (6) and N3P3[OC6H4CH2CN·CuCl]6[PF6]6 (7),were incorporated inside SiO2 through the sol–gel method. The metal–organic nanocomposites of the general formula N3P3[OC6H4CH2CN·TiClCp2]6·nSiO2 (G 1 ), N3P3[OC6H4N·W(CO)5nSiO2 (G 2 ), N3P3[OC6H4CH2CN·Mo(CO)5]6·nSiO2 (G 3 ), N3P3(O6H5)5OC5H4N·CpRu(PPh3)2][PF6nSiO2 (G 4 ), [N3P3(O2C12H8)2OC5H4N·Ag(PPh3)][OSO2CF3nSiO2 (G 5 ), N3P3[OC6H5]5[OC5H4N·Cu][PF6]·(SiO2) n (G 6 ), and N3P3[OC6H4CH2CN·CuCl]6[PF6]6·(SiO2) n (G 7 ), were characterized by IR spectroscopy; 12C, 31 P and 29Si MAS NMR measurements as well as UV–Visible diffuse reflectance spectra, indicating the presence of the respective organometallic derivatives of the cyclotriphosphazene incorporated into SiO2. Pyrolysis of these nanocomposites under air at 800 °C gives rise to nanostructured metal-oxides and metal phosphates incorporated into amorphous SiO2, with the presence in some cases of complexes phase mixtures. From some precursors, we obtained metal-oxides/phosphates nanoparticles separated from the SiO2 nanoparticles instead the oxides/phosphates nanoparticles inside the SiO2 matrix. Additionally and for comparison purposes, we used the compound N3P3[NH(CH2)3Si(OEt)3]6 as gelator. Nanocomposites (G′ 1 ), (G′ 2 ) and (G′ 3 ) exhibited mainly morphological differences while in some cases composition differences when using TEOS as gelator. Some simple metal-containing compounds as (O3SCF3)Ag(PPh3)(HOC5H4N), [CuCl2·NC5H4OH] and [CuCl2·NCCH2C6H4OH]—which are useful models of the most complexes (G 5 ), (G 6 ) and (G 7 ) were also prepared and incorporated in amorphous silica. Their pyrolytic products were compared with those of more complex cyclotriphosphazene analogous. Interestingly, the pyrolysis of the nanocomposite [(O3SCF3)Ag(PPh3)(HOC5H4N)][SiO2] n affords the firstly-reported materials containing Ag2O along with SiO2 nanoparticles.  相似文献   

11.
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   

12.
Tianxu Sun  Zhiqiang Fan 《Polymer》2010,51(14):3091-2485
Heterobinuclear cobalt and nickel complex {2-[2,6-R2-C6H3NC(CH3)-(CH3)CN-(3,5-R2′)C6H2-CH2-(3′,5′-R2)C6H2NC(CH3)]-6-[2,6-R2-C6H3NC(CH3)] pyridine}CoCl2NiBr2 (R = isopropyl) (N5CoNi) was prepared by reaction of pentadentate nitrogen ligand containing 2,6-bis(imino)-pyridine and α-diimine moieties with CoCl2 and NiBr2(DME) in turn. The complex was applied as catalyst for ethylene polymerization activated by AlEt3, MMAO and AlEt3/[PhMe2NH] [B(C6F5)4] respectively. The performance of the heterobinuclear complex in ethylene polymerization was compared with corresponding mononuclear complexes (α-diimine nickel bromide and 2,6-bis(imino)-pyridine cobalt chloride) and their equivalent mixture (binary complexes). When the complex N5CoNi was activated by AlEt3 or MMAO, its ethylene polymerization activity was lower than its control, the binary complexes. Both heterobinuclear complex and binary complex produced PE with bimodal molecular weight distribution. The amount of high-molecular-weight polyethylene produced by nickel center of N5CoNi was less than the binary complexes, which reveals that productivity of nickel center of N5CoNi is selectively suppressed. When the heterobinuclear complex N5CoNi is activated by AlEt3/[PhMe2NH][B(C6F5)4], the relative productivity of nickel center increased, although the total activity of catalyst decreased compared with AlEt3 as cocatalyst. With respect to AlEt3, [PhMe2NH][B(C6F5)4] can preferably activate nickel center of heterobinuclear complex. The results suggest that metal site in the heterobinuclear complex is selectively activated by cocatalyst.  相似文献   

13.
In two previous papers (Kinget al., J. Organomet. Chem. 19, 327, 1969; Pannellet al., Organometallics 9, 859, 1990), the synthesis and X-ray structure of the two tetramethyl disilyl complexes [(η5-C5H5) Fe(CO)2]2Si2Me4 (I) and Si2Me4[(η5-C5H4) Fe(CO)2CH3]2 (II) were reported. ComplexII is obtained fromI [2]. However, attempts to form other derivatives fromI have generally failed. In the chemical process to getII fromI, an intermediate complex, Si2Me4[(η5-C5H4) Fe(CO)2] 2 2? (III), is probably formed. This is similar to complexII without the two methyl groups bonded to the Fe atoms. Therefore, a theoretical study that may shed some light on the intermediate structure, stability, and reactivity is justified. We have developed theoretical studies consisting of extended Huckel electronic structure calculations on the simulated intermediate geometry. The results obtained from these calculations suggest that it might be stable enough to form during reactions of complexI. The more reactive sites, which suggest reaction alternatives, are pointed out.  相似文献   

14.
Two new polymeric triorganotin(IV) complexes R3Sn{O2CC6H4[N=C(H)}{C(CH3)CH(CH3)-3-OH]-p} n ([Me3Sn(LH)] n : 1) and ([Ph3Sn(LH)] n : 2) containing a 4-[(2Z)-(3-hydroxy-1-methyl-2-butenylidene)amino]benzoate (LH) framework were prepared. Both compounds have been characterized by 1H, 13C, 119Sn NMR, IR and 119Sn Mössbauer spectroscopic techniques in combination with elemental analyses. The crystal structures of complexes 1 and 2 reveal that they exist as polymeric zig-zag chains in which the LH-bridged Sn-atoms adopt a trans-R3SnO2 trigonal bipyramidal configuration with R groups in the equatorial positions and the axial sites occupied by an oxygen atom from the carboxylate ligand and the alcoholic oxygen atom of the next carboxylate ligand in the chain. The carboxylate ligands coordinate in the zwitterionic form with the alcoholic proton moved to the nearby nitrogen atom.  相似文献   

15.
The oxidative addition of compounds RBr to [PtMe2(bpox)], 1, bpox = 2,5-bis(2-pyridyl)-1,3,4-oxadiazole gave the corresponding organoplatinum(IV) complexes [PtBrMe2(R)(bpox)], 2, R = CH2CO2H; 3, R = CH2-4-C6H4CO2H; 4, R = CH2-4-C6H4CH2CO2H, whereas the reaction with BrCH2CH2CO2H gave only the platinum(II) complex [PtBrMe(bpox)], 5. The organoplatinum(IV) complexes with carboxylic acid substituents form unusual supramolecular structures in the solid state through hydrogen bonding interactions, some of which are supramolecular polymers.  相似文献   

16.
The synthesis of a series of fourteen 4-alkoxy-1,1,1-trihalo-3-alken-2-ones (2,3) [CX3COC(R2)=C(R1)OMe, where X = Cl, F; R1/R2 = Me/H, Bu/H, i-Bu/H, Ph/H, Thien-2-yl/H, –(CH2)4–, –CH(CH2)4CH(CH2)2–] from the acylation reactions of acetals (1) with trichloroacetyl chloride or trifluoroacetic anhydride in the presence of equimolar amounts of pyridine and imidazolium based ionic liquid ([BMIM][BF4] or [BMIM][PF6]) is reported. The reaction time, yields and IL recyclation are also investigated and this method showed advantages over the methods described in the literature.  相似文献   

17.
α-Diimine nickel dibromide complexes of dibromo[N,N’-bis(2,6-diisopropylphenyl)-2,3-butanediimine]nickel(II) (A) and dibromo[N,N’-(phenanthrene-9,10-diylidene)bis(2,6-diisopropylaniline)]nickel(II) (B) were synthesized under controlled conditions. The catalysts A, B and mixed of 1:1 weight ratio of them (C) were activated by methylaluminoxane and were used for propylene polymerization in a semi-batch reactor. In study of the catalytic systems behavior, activities, glass transition temperature (T g) and viscosity average molecular weight (M v) values related to the catalyst C were between those related to the catalysts A and B under same conditions. The highest and the lowest molecular weights of the obtained polymers were produced by the catalysts B and A which were about 80,000 and 70,000 (g/mol) under same conditions, respectively. The T g of polypropylenes produced by the catalysts was about ?34 °C. The resulting polymers had similar behavior with ethylene-propylene copolymer which it could be due to formation of ethylene-type units in the polymer chain.  相似文献   

18.
Two new cadmium(II) and lead(II)-thiocyanato coordination polymers with 5,5′-dimethyl-2,2′-bipyridine (5,5′-dm-2,2′-bpy) as chelating ligands were synthesized and characterized by elemental analysis, IR and 1H NMR spectroscopy and by X-ray crystallography. Thermal and electrochemical properties were also studied as well. These complexes have formed formula [Cd(5,5′-dm-2,2′-bpy)(NCS)2]n (1) and [Pb(5,5′-dm-2,2′-bpy)(CH3COO)(NCS)]n (2). The coordination numbers of CdII in 1 and PbII in 2 are six (CdN4S2) and seven (PbN3O3S2), respectively. In 2, “stereo-chemically active” electron lone pairs and the coordination spheres were hemidirected. Bridging properties of thiocyanato anions in 1 and 2 created one- and two-dimensional coordination polymers, respectively. The supramolecular features in these complexes were guided and controlled by weak directional intermolecular interactions.  相似文献   

19.
Two coordination polymers, namely, [Ni(L)(C2H3N)(H2O)5] n (1), and [Mn(L)(H2O)2] n (2) have been hydro(solvo)thermally synthesized through the reaction of 4-(4-hydroxypyridinium-1-yl)phthalic acid (H2L) with divalent nickel and manganese salts. As a result of various coordination modes of the versatile 4-(4-hydroxypyridinium-1-yl)phthalic acid, these compounds exhibit structural diversity. Complex 1 exhibits a 3D coordination framework through the rich hydrogen bond. Complex 2 exhibits a 3D coordination network based on layers. These complexes have been characterized by powder X-ray diffractions (PXRD), IR spectroscopy, elemental analysis, thermogravimetry, single-crystal X-ray crystallography and solid UV spectroscopy.  相似文献   

20.
Three mixed-metal nitrilotriacetates [Ba(H2O)3Co(nta)Cl]n (1), [Ba(H2O)3Ni(nta)Cl]n (2), and [Ba(H2O)3Cu(nta)Cl]n (3) (H3nta = nitrilotriacetic acid) were prepared by the reaction of M2+ ions (M = Co, Ni, and Cu), K3nta, and Ba2+ ions in water. The reaction of complexes 1 and 2 with CuSO4·5H2O afforded [Co(H2O)6]n[Cu2(nta)2]n·2nH2O (4) and [Ni(H2O)6]n[Cu2(nta)2]n·2nH2O (5), respectively. The reaction mechanism was elucidated. The crystal structure analyses indicate that the Ba2+ ions formed one-dimensional (1D) zigzag chains in complex 3, and the chains were connected by Cu(nta)? anions to form a three-dimensional network. On the other hand, in complexes 4 and 5, the Cu(nta)? anions formed 1D zigzag chains, and the [Co(H2O)6]2+ (or [Ni(H2O)6]2+) cations existed as isolated units.  相似文献   

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