首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 651 毫秒
1.
A new mellitate complex [Cu3(μ2-mellitate)(μ2-H2O)(H2O)2·H2O]n 1 has been synthesized by the reaction of mellitic acid and Cu(CH3COO)2·H2O in the presence of base. Crystallographic data for 1: C12H8O16Cu3, Mr = 598.80, orthorhombic, Pbcn, a = 8.4378(6), b = 10.0396(7), c = 17.6799(12)A, V = 1497.70(18)A^3, Z = 4, De = 2.656 g/cm^3, μ = 4.327 mm^-1, F(000) = 1180, R = 0.0431 and wR = 0.0964 for 1075 observed reflections (I 〉 2σ(I)). X-ray crystal structural analysis revealed that the mellitate anions behave as the bridging ligands and link eight copper atoms repeatedly to form a novel three-dimensional metal-organic coordination polymer with two different rhombic tunnels in the solid-state structure.  相似文献   

2.
A metal-organic coordination polymer [Cd(bpy)(BDC)]n·nbpy (bpy = 2,2-bipyri- dine, H2BDC = terephthalic acid) has been hydrothermally synthesized and structurally characteri- zed by elemental analysis, IR spectrum, TG and single-crystal X-ray diffraction. The complex crystallizes in monoclinic, space group C2/c with a = 15.723(5), b = 21.695(5), c = 7.576(5) , β = 116.171(7)o, V = 2319.3(18) 3, C28H20CdN4O4, Mr = 588.88, Dc = 1.686 g/cm3, μ(MoKα) = 0.987 mm-1, F(000) = 1184, Z = 4, the final R = 0.0464 and wR = 0.0831 for 1882 observed reflections (I > 2σ(I)). It exhibits a three-dimensional network with channels constructed from one-dimensional coordination chains via C–H···O hydrogen bonds and significant aromatic π-π stacking interactions.  相似文献   

3.
付二霞  曹高  石磊  胡艾希 《结构化学》2013,32(5):709-713
The title compound 2(C22H28N+O3)·H2O·2Cl-was synthesized by the reaction of 2-bromo-1-[4-(benzyloxy)phenyl]-1-pentone with 2,2'-azanediyldiethanol. The crystal determined by X-ray diffraction analysis belongs to the monoclinic system, space group Pc with a = 18.312(3), b = 14.838(3), c = 7.6227(14) , β = 97.981(4)°, Z = 2, Mr = 797.82, V = 2051.1(6) 3, Dc = 1.292 g/cm3, S = 0.956, μ = 0.21 mm-1, F(000) = 852, the final R = 0.0625 and wR = 0.1428 for 5683 observed reflections (Ⅰ > 2σ(Ⅰ)). Flack parameter is 0.10(9). The title compound is composed by four non-coplanar ring systems, two benzenes and two morpholines. One morpholine ring (C(3)-C(4)-N(1)-C(1)-C(2)-O(1)) forms a chair conformation, while the other (C(4)-C(3)-O(2)-C(6)-C(5)-N(1)) assumes a boat conformation. X-ray crystal structure displays extensive N-H…Cl and O-H…Cl intermolecular hydrogen bonds. The preliminary antidepressant activity test indicates that the inhibition ratio of SERT (5-HT Transporter) was 35.9% at the dosage of 10.0 mg/L.  相似文献   

4.
Neutral Ni(II) salicylaldiminato complexes activated with modified methylaluminoxane as catalysts were used for the vinylic polymerization of norbornene. Catalyst activities of up to 7.08 × 104 kgpol/(molNi · h) and viscosity‐average molecular weights of polymer up to 1.5 × 106 g/mol were observed at optimum conditions. Polynorbornenes are amorphous, soluble in organic solvents, highly stable, and show glass‐transition temperatures around 390 °C. Catalyst activity, polymer yield, and polymer molecular weight can be controlled over a wide range by the variation of the reaction parameters such as the Al/Ni ratio, monomer/catalyst ratio, monomer concentration, polymerization reaction temperature, and time. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2680–2685, 2002  相似文献   

5.
A two-dimensional coordination polymer, [Cd(AIP)(Bpy)]n·nBpy, was hydrother- mally synthesized by the reaction of hydrate cadmium acetate with 5-aminoisophthalic acid, lithium hydroxide, vanadiumpentoxide, sodium chloride and 2,2′-bipyridyl in water solution. It crystallizes in orthorhombic, space group C2221, absolute structure parameter 0.00(7), with a = 15.336(4), b = 22.390(6), c = 14.257(3) , V = 4896(2)3, C28H21CdN5O4, Mr = 603.90, Z = 8, F(000) = 2432, Dc = 1.639 g/cm3, μ = 0.939 mm–1, T = 298(2) K, S = 1.001, R = 0.0296 and wR = 0.0813 for 5522 observed reflections (I > 2σ(I)). In the title complex, each 5-aminoisophthalate ligand bridges three cadmium(II) ions to form a two-dimensional layer structure.  相似文献   

6.
The title compound {[Mn(H2BPTC)(tpy)(H2O)]·(H2O)3}n (1, H4BPTC = 1,1′- biphenyl-2,2′,6,6′-tetracarboxylic acid, tby = 2,2′:6,2′′-terpyridine) has been synthesized by the hydrothermal reaction, and its structure was determined by X-ray diffraction and characterized by elemental analysis, IR spectrum and thermogravimetric analysis. The crystal is of monoclinic, space group P21/c with a = 10.971(2), b = 20.776(4), c = 14.332(3) , β = 109.25(3)o, MnC31H27N3O12, Mr = 688.50, V = 3084.1(10) 3, Dc = 1.483 g/cm3, F(000) = 1420, μ = 0.498 mm-1, S = 1.066 and Z = 4. The final refinement gave R = 0.0447 and wR = 0.1103 for 5107 observed reflections with I > 2σ(I). The title complex has a {[Mn(H2BPTC)(tpy)(H2O)]}n chain structure, and the hydrogen bonding interactions make it more stable. Each chain is further connected to the adjacent ones through π···π, C-H···π and rich hydrogen bonds to form a metal-organic coordination polymer.  相似文献   

7.
A series of para‐phenyl‐substituted α‐diimine nickel complexes, [(2,6‐R2‐4‐PhC6H2N═C(Me))2]NiBr2 (R = iPr ( 1 ); R = Et ( 2 ); R = Me ( 3 ); R = H ( 4 )), were synthesized and characterized. These complexes with systematically varied ligand sterics were used as precatalysts for ethylene polymerization in combination with methylaluminoxane. The results indicated the possibility of catalytic activity, molecular weight and polymer microstructure control through catalyst structures and polymerization temperature. Interestingly, it is possible to tune the catalytic activities ((0.30–2.56) × 106 g (mol Ni·h)?1), polymer molecular weights (Mn = (2.1–28.6) × 104 g mol?1) and branching densities (71–143/1000 C) over a very wide range. The polyethylene branching densities decreased with increasing bulkiness of ligand and decreasing polymerization temperature. Specifically, methyl‐substituted complex 3 showed high activities and produced highly branched amorphous polyethylene (up to 143 branches per 1000 C).  相似文献   

8.
Reactions of Lithium Hydridosilylamides RR′(H)Si–N(Li)R″ with Chlorotrimethylsilane in Tetrahydrofuran and Nonpolar Solvents: N‐Silylation and/or Formation of Cyclodisilazanes The lithiumhydridosilylamides RR′(H)Si–N(Li)R″ ( 2 a : R = R′ = CHMe2, R″ = SiMe3; 2 b : R = R′ = Ph, R″ = SiMe3; 2 c : R = R′ = CMe3, R″ = SiMe3; 2 d : R = R′ = R″ = CMe3; 2 e : R = Me, R′ = Si(SiMe3)3, R″ = CMe3; 2 f – 2 h : R = R′ = Me, f : R″ = 2,4,6‐Me3C6H2, g : R″ = SiH(CHMe2)2, h : R″ = SiH(CMe3)2; 2 i : R = R′ = CMe3, R″ = SiH(CMe3)2) were prepared by reaction of the corresponding hydridosilylamines RR′(H)Si–NHR″ 2 a – 2 i with n‐butyllithium in equimolar ratio in n‐hexane. The unknown amines 1 e – 1 i and amides 2 f – 2 i have been characterized spectroscopically. The wave numbers of the Si–H stretching vibrations and 29Si–1H coupling constants of the amides are less than of the analogous amines. This indicates a higher hydride character for the hydrogen atom of the Si–H group in the amide in comparison to the amines. The 29Si‐NMR chemical shifts lie in the amides at higher field than in the amines. The amides 2 a – 2 c and 2 e – 2 g react with chlorotrimethylsilane in THF to give the corresponding N‐silylation products RR′(H)Si–N(SiMe3)R″ ( 3 a – 3 c , 3 e – 3 g ) in good yields. In the reaction of 2 i with chlorotrimethylsilane in molar ratio 1 : 2,33 in THF hydrogen‐chlorine exchange takes place and after hydrolytic work up of the reaction mixture [(Me3C)2(Cl)Si]2NH ( 5 a ) is obtained. The reaction of the amides 2 a – 2 c , 2 f and 2 g with chlorotrimethylsilane in m(p)‐xylene and/or n‐hexane affords mixtures of N‐substitution products RR′(H)Si–N(SiMe3)R″ ( 3 a – 3 c , 3 f , 3 g ) and cyclodisilazanes [RR′Si–NR″]2 ( 6 a – 6 c , 6 f , 6 g ) as the main products. In case of the reaction of 2 h the cyclodisilazane 6 h was obtained only. 2 c – 2 e show a very low reactivity toward chlorotrimetyhlsilane in m‐xylene and toluene resp.. In contrast to Me3SiCl the reactivity of 2 d toward Me3SiOSO2CF3 and Me2(H)SiCl is significant higher. 2 d react with Me3SiOSO2CF3 and Me2(H)SiCl in n‐hexane under N‐silylation to give RR′(H)Si–N(SiMe3)R″ ( 3 d ) and RR′(H)Si–N(SiHMe2)R″ ( 3 d ′) resp. The crystal structures of [Me2Si–NSiMe3]2 ( I ) ( 6 f , 6 g and 6 h ) have been determined.  相似文献   

9.
1INTRODUCTION Recently,cyano-bridged lanthanide-transition me-tal complexes have been extensively investigateddue to their potential applications as precursors in the preparation of rare earth orthoferrites,fluores-cent and magnetic materials[1].Various complexes of this system have been obtained in order to ex-plore the relations between structures and pro-perties by using different ligands,such as DMF,4,4?-bipy,and so on,to fill the coordination sites of lanthanide ions[2~9].But up to…  相似文献   

10.
1INTRODUCTION There is currently considerable interest in the ra-tional design and controlled synthesis of metal-organic frameworks(MOFs)with unique structural motif on account of their promising applications as catalysts,gas storage,selective separation,sensor,ion exchange and magnetic materials[1,2].Particu-larly,the supramolecular architectures with helical structures have received much more attention over the past decades owing to their specific functions in biology.It is well recogn…  相似文献   

11.
Two new transition metal complexes, [Ni(bipy)2Cl]·ClO4 (bipy = 2,2'-bipyridine) 1 and [Zn(bipy)2Cl]·BF4 2, have been synthesized and characterized by single-crystal X-ray diffraction analysis. Both 1 and 2 crystallize in monoclinic space group P21/n with Z = 4. For 1, a = 10.776(1), b = 12.067(1), c = 16.146(2) , β = 93.021(2)o, V = 2031.9(4) 3, Mr = 505.98, Dc = 1.654 g/cm3, μ = 1.255 mm–1, F(000) = 1032, the final R = 0.0406 and wR = 0.1002 for 3983 observed reflections with I > 2σ(I). For 2, a = 10.758(4), b = 12.058(4), c = 16.135(5) , β = 104.57(1)o, V = 2025.7(12) 3, Mr = 500.00, Dc = 1.639 g/cm3, μ = 1.396 mm–1, F(000) = 1008, the final R = 0.0470 and wR = 0.1237 for 3759 observed reflections with I > 2σ(I). The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. A one-dimen-sional zigzag double hydrogen-bonding-chain is generated by the intermolecular M-bipy ···anion···bipy- M hydrogen bonding interactions between the chelating ligands of bipy and anion.  相似文献   

12.
The title compound, {[Ag2(bipy)2(H2O)2]·pydc·2H2O}n (bipy=4,4'-bipyridine, pydc= pyridine-3,5-dicarboxylate), has been synthesized by the reaction of Ag2O with pydc and bipy in CH3OH solution. It crystallizes in the monoclinic system, space group C2/c with a=21.419(8), b=7.515(3), c=18.070(7), β=108.273(6)°, Mr=765.27, V=2761.9(17)3, Z=4, Dc=1.840 g/cm3, F(000)= 1528, μ=1.478 mm-1, the final R=0.0307 and wR=0.0681. The structure determined demonstrated that the Ag(I) is three-coordinated by two nitrogen atoms from bipy and one water molecule, forming a one-dimensional coordination polymer [Ag2(bipy)2(H2O)2]n2n+, which is further linked to generate a two-dimensional layer structure via Ag…Ag attractions.  相似文献   

13.
A new tin complex Sn(CH3 HPPDA)Cl4 (1) was prepared from SnCl4·5H2O with (2,3-f)-pyrazino(1,10)phenanthroline-2,3-dicarboxylic acid (H2PPDA) by solvothermal reaction in methanol, and characterized by single-crystal X-ray diffraction analysis, optical absorption spectrum and photoluminescence. Compound 1 crystallizes in a monoclinic centrosymmetric space group of P21/c with a = 12.418(2), b = 11.9467(12), c = 15.845(3), β= 107.948(7)°, V = 2236.2(6)3 , Z = 4, Mr = 594.78, Dc = 1.767 g/cm3 , μ= 1.651 mm-1 , F(000) = 1160, S = 1.023 and T = 293(2) K. The final R = 0.0847 and wR = 0.2431 for 3144 observed reflections with Ⅰ > 2σ(Ⅰ). The discrete mononuclear Sn(CH 3 HPPDA)Cl 4 complex is connected into a supramolecular network of 1 by intramolecular and intermolecular C-H···Cl and intermolecular C-H···O hydrogen bonding interactions. Compound 1 displays fluorescence with a lifetime value of about 7.58 ns in the visible region under visible-light excitation, and the origin of the luminescent emission is primarily assigned to the combination of intraligand charge-transfer of CH3 HPPDA and Cl--to-CH 3 HPPDA charge-transfer mechanism which is probed by the density of states (DOS) calculations.  相似文献   

14.
李悦生 《高分子科学》2013,31(6):885-893
Vanadium(Ⅲ) complexes bearing thiophenol-phosphine ligands (2a-2b) (2-R-6-PPh2-C6H2S) VCl2(THF)2 (2a: R=H; 2b: R=Me3Si) were prepared from VCl3(THF)3 by treating with 1.0 equiv of the ligand in tetrahydrofuran in the presence of excess triethylamine. The two complexes were characterized by FTIR and mass spectra as well as elemental analyses. On activation with Et2AlCl, these complexes exhibited high catalytic activities (up to 22.1 kg PE/(mmolV·h·bar)) even at high temperature (70℃), and produced high molecular weight polymers with unimodal molecular weight distributions, indicating the polymerization took place in a single-site nature. This result may be attributed to benefits of introduction of second-row donor atoms for adjusting charge density of the vanadium centers. In addition, these complexes also exhibited high catalytic activities for ethylene/1-hexene copolymerization. Catalytic activity, comonomer incorporation and polymer molecular weight can be controlled in a wide range by the variation of catalyst structure and the reaction parameters such as Al/V molar ratio, comonomer feed concentration and polymerization reaction temperature.  相似文献   

15.
《Polyhedron》2002,21(25-26):2531-2535
The reactivities of [trans-R2MoO(NNPhR′)(o-phen)], R=R′=Me (1); R=Me, R′=Ph (2); R=Ph, R′=Me (3); R=R′=Ph (4), toward (i) neutral 1,1-disubstituted hydrazines, R′PhNNH2 and (ii) 1,1-disubstituted hydrazine hydrochlorides, R′PhNNH2·HCl, R′=Me, Ph, were studied in acetonitrile. In the first case, no condensation reaction of the free oxo group was observed under different experimental conditions. In the second case, using a 1:1 precursor/hydrazine hydrochloride molar ratio, the oxo group was also unreactive, instead one methyl or phenyl group bonded to molybdenum was displaced as methane or benzene and was subsequently substituted by one chloride ligand affording complexes formulated as [trans-RClMoO(NNPhR′)(o-phen)], R=R′=Me (5); R=Me, R′=Ph (6); R=Ph, R′=Me, (7)·MeCN; R=R′=Ph, (8)·MeCN. Finally, when a 1:2 precursor/hydrazine hydrochloride molar ratio was used, both methyl and phenyl groups were substituted affording complexes formulated as [trans-Cl2MoO(NNPhR′)(o-phen)], R′=Me (9), R=Ph (10). The new organometallic compounds were characterised by IR, UV–Vis and 1H NMR spectroscopy while the crystal and molecular structure of 6 was determined by X-ray diffraction analysis.  相似文献   

16.
Two homochiral metallosalen complexes, Ni(salen) (salen = (1R,2R)-(-)-diaminocyclohexane-N,N'-bis(3-tert-butyl-5-(4'-benzoic acid)-salicylidene) 1 and Cu(salen) 2, have been synthesized and characterized by IR, microanalysis, TGA, powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P21212 with Z = 4. For 1, a = 12.082(2), b = 15.447(3), c = 18.784(4) , V = 3505.7(12) 3, Mr = 731.50, Dc = 1.386 g/cm3, μ = 0.606 mm–1, F(000) = 1544, the final GOOF = 1.043, R = 0.0496 and wR = 0.1248 for 4791 observed reflections with I > 2σ(I). For 2, a = 12.181(2), b = 15.501(3), c = 18.877(4) , V = 3564.3(12) 3, Mr = 736.33, Dc = 1.372 g/cm3, μ = 0.665 mm–1, F(000) = 1548, the final GOOF = 1.062, R = 0.0575 and wR = 0.1508 for 4562 observed reflections with I > 2σ(I). The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. An infinite two-dimensional network is generated by hydrogen bonding interactions and intermolecular π···π interactions.  相似文献   

17.
We report a study of the conditions of the phosphorylation reaction for the preparation of aromatic polyamides using the Higashi reaction medium. For poly(p-phenylene terephthalamide) (PPD-T), the optimum conditions are: reaction temperature, 115°C; monomer concentration, C = 0.083 mol/L; and ratio of triphenyl phosphite (TPP) to monomer, 2.0. These optimum conditions produce PPD-T having ηinh = 6.2 dL/g. At temperatures of 120°C and above PPD-T precipitates from the reaction mixture, leading to lower molecular weights. At lower temperatures the reaction mixture gels, and the gel time decreases with increasing reaction temperature. However, polycondensation continues in the gel state. Monomer concentrations C = 0.10 mol/L and above produce precipitation and yield polyamides of lower molecular weight. For the preparation of poly(p-benzamide) (PBA), the optimum ratio of TPP to monomer is 0.6 for either p- aminobenzoic acid or N-4-(4′-aminobenzamido)benzoic acid. In the former case the inherent viscosity of polymer prepared at 115°C showed little dependence upon the concentration of the monomer. The highest value, ηinh = 1.8 dL/g, was obtained with C = 0.40 mol/L and a TPP/monomer ratio of 0.6. However, for the same TPP/monomer ratio, the monomer containing a preformed amide linkage, N-4-(4′-aminobenzamido)benzoic acid, gave PBA with ηinh = 4.6 dL/g when the monomer concentration is 0.33 mol/L. This is the highest value reported for PBA using the phosphorylation reaction. In A?A + B?B polycondensation, examples in which one of the monomers contained one or two preformed amide linkages produced polyamides having ηinh = 7.8 and 8.9 dL/g, respectively.  相似文献   

18.
The crystal structure of the title compound (C22H17BrO5 , Mr = 441.27) has been determined by single-crystal X-ray diffraction. The crystal is of orthorhombic system, space group Pna21 with a = 11.76(1), b = 14.58(1), c = 11.52(1), V = 1973.93 , Z = 4, Dc = 1.485 g/cm3 , F(000) = 896, μ(MoKα) = 2.113 mm-1 , the final R = 0.0394 and wR = 0.0809 for 3918 observed reflections (Ⅰ > 2 (Ⅰ)). The single-crystal X-ray diffraction data indicate that the C=C bond is in an E-configuration. The intramolecular C(10)-H(10B)···O(4) and intermolecular C(17)-H(17)···O(4) hydrogen bonds contribute to the stability of the structure.  相似文献   

19.
It is possible to identify three distinct types of polymer adhesion on the basis of the physical state of adhesive and adherend: (1) rubbery polymer–rubbery polymer (R–R adhesion); (2) rubbery polymer–glassy polymer (R–G adhesion); (3) rubbery polymer–nonpolymer (R–S adhesion). Limitations of the diffusion and adsorption theories and their conflicting results are discussed within the framework of the proposed classification. By defining the physical state of the polymer as an adhesive or as an adherend, it is possible to eliminate many of the discrepancies commonly noted in attempted application of the diffusion and adsorption theories. As predicted by the Bueche-Cashin-Debye equation, the diffusion of a polymer into another should be greatly reduced as it changes from the rubbery to the glassy state. For this reason, diffusion, which depends to a great extent on the physical state of the polymer, is actually a limited, selective process. Assuming a 1013 poise bulk viscosity at glass temperature, self-diffusion constants of forty polymers were calculated to be 10?21cm.2/sec. or 10?5A.2/sec. This slow rate of diffusion is unmeasurable and insignificant. Adsorption, which is less dependent on the physical state of the polymer, is more frequently encountered.  相似文献   

20.
1INTRODUCTION Investigation of the coordination chemistry of copper(II)continues to be stimulated by interest in developing modes for copper proteins and in under-standing the factors which give rise to the seemingly infinite variety of distortions from regular stereo-chemistry observed in Cu(II)complexes[1,2].For more than decades,due to the unique coordination polyhedra and their easy preparation,tripodal copper complexes have attracted much attention in addition to their special chemi…  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号