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1.
刘勇路  陈砚美  高倩  刘玮  李亚红  李武 《结构化学》2014,33(8):1171-1183
The employment of N-hydroxy-pyridine-2-carboxamidine in the coordination chemistry of zinc(Ⅱ), nickel(Ⅱ) and manganese(Ⅱ) under solvothermal conditions is reported. Four complexes of compositions, [Zn2(O2CMe)3{(py)C(NH2)NOH}4](OH)(1), [Zn4(OH)2{(py)C(NH2)-NO}4Cl2]·3MeCN(2), [Ni(SO4)(H2O){(py)C(NH2)NOH}2]·H2O(3) and [Mn(SO4){(py)C(NH2)-NOH}2]n(4), have been synthesized by rationally choosing different metal salts and dexterously employing acetate and sulfate ions as the bridging groups. Luminescent properties for 2 suggested strong emission in the solid state at room temperature. Variable temperature(2.0~300 K) magnetic studies for the linear chain complex 4 indicate weak antiferromagnetic Mn(Ⅱ)···Mn(Ⅱ) exchange interactions.  相似文献   

2.
3.
A new kind of Schiff base HL(HL= 1-phenyl-3-methyl-4-(p-methylbenzoyl)-5-pyrazolone with L-Leucine methyl ester) and complexes Ni L′_2·0.75C_2H_5OH·0.25H_2O,Cu L′′2(L′ = 1-phenyl-3-methyl-4-(p-methylbenzoyl)-5-pyrazolone with L-leucine ethyl,L′′ = 1-phenyl-3-methyl-4-(p-methylbenzoyl)-5-pyrazolone with L-leucine) have been synthesized and structurally determined by X-ray diffraction. For HL: crystal structure determination indicates that there are two independent HLs with different conformations in one asymmetric unit. For complex 1: the Ni(Ⅱ) ion is six-coordinated by two carbonyl oxygen atoms from pyrazolone ring,two nitrogen atoms from different HL′ and two oxygen atoms from L-Leucine ethyl ester to form a distorted octahedral geometry. For complex 2: the Cu(Ⅱ) ion is four-coordinated by one carbonyl oxygen atom from the pyrazolone ring,one nitrogen atom from HL′′,and two different carboxylic oxygen atoms from L-leucine with the same conformation to form a distorted quadrilateral geometry.  相似文献   

4.
A pyridine-contained Schiff base ligand L(L =(pyridine-2-vinyl)hydrazine) has been synthesized and fully characterized. By self-assembly of the ligand with HgI_2, a binuclear complex Hg_2I_4L(C) was obtained. The structures of L and C were analyzed through single-crystal X-ray diffraction. L crystallizes in monoclinic, space group P21/n with a=11.286(5), b=3.981(5), c=23.865(5) ?, β=100.043(5)°, V=1056(1) ?~3, Z=4, Dc=1.323 g/m~3, F(000)=440, Μr=210.24, μ=0.084 mm~(-1), the final R=0.0928 and w R=0.2867 for 6955 observed reflections with I 2(I). The complex is of monoclinic system, space group P21/n with a=8.706(5), b=17.468(5), c=14.675(5) ?, β=93.922(5)°, V=2227(2) ?~3, Z=4, Dc=3.338 g/m~3, F(000)=1928, Μr=1119.02, μ=19.321 mm~(-1), the final R=0.0366 and w R=0.1276 for 3920 observed reflections with I 2(I). The structural analysis revealed that the molecule of L possesses a well planar structure. However, in the complex, the coordinated ligand distorts greatly. The absorption spectra of L and the complex in ethanol were experimentally and theoretically studied. The result indicates that the complex exhibits different absorption spectrum compared with the free ligand.  相似文献   

5.
The ligand of N-(2-hydroxybenzylideneamino)-1,8-naphthalimide (HL) and its metal complexes of CuL2 (1) and CoL2 (2) have been synthesized. Elemental analysis, IR and X-ray single-crystal diffraction characterizations for 1 and 2 have been carried out. In the complexes of 1 and 2, the central metallic ions of Cu2+ and Co2+ coordinate with two deprotonated ligands of L-, respectively and adopt distorted square planar geometries. The thermal analysis result shows that the two complexes undergo two similar decomposition processes because of their similar geometric configurations. For the two complexes, fluorescence spectra measurements indicate that complex CoL2 emits stronger blue fluorescence than HL and the complex CuL2 does not emit fluorescence at all.  相似文献   

6.
Three new Keggin polyoxometalates, [Zn(phen) 3 ] 2 [SiW 12 O 40 ]·5H 2 O(1), [Co(phen) 3 ] 2 [SiW 12 O 40 ](2) and [Ni(phen) 3 ] 2 [SiW 12 O 40 ]·2H 2 O(3)(phen=1,10′-phenanthroline) have been hydrothermally synthesized and characterized by elemental analysis, IR, crystal X-ray diffraction, thermogravimetric analyses(TGA) and fluorescence techniques. Complex 1, crystallized in the triclinic space group P1, consists of one [SiW 12 O 40 ] 4– anion, two discrete [Zn(phen) 3 ] 2+ cations and five crystal water molecules. Complexes 2 and 3 have the similar configuration to complex 1, but they crystallized in the monoclinic space group C2/c. Variable-temperature magnetic susceptibilities of complexess 2 and 3 reveal antiferromagnetism and ferromagnetism, respectively.  相似文献   

7.
The syntheses, structures and catalytic activities of two yttrium complexes supported by pyrrolide ligands are reported. Treatment of Y(N(Si Me3)2)3 with one equivalent of H3bptd(H3bptd = 1,9-bis(2-pyrrolyl)-2,5,8-triazanona-1,8-diene) in THF gave a complex of composition [Y(bptd)(THF)]2(1). Reaction of Y(N(Si Me3)2)3 with one equivalent of H3tpa(H3tpa = tris(pyrrolyl-?-methyl)amine) in THF generated [Y(tpa)(THF)3](2) in good yield. Complexes 1and 2 have been characterized by single-crystal X-ray diffraction, elemental analyses and NMR spectroscopy. Complex 1 is dinuclear. The two metal centers are doubly bridged by two amine nitrogen atoms to form a Y–N–Y–N four-membered rhombus ring. The geometries of Y3+ ions in 1and 2 are well described as pentagonal bipyramid and capped octahedron, respectively. The ring-opening polymerization reactions of ?-caprolactone initiated by 1 and 2, respectively, were investigated. They both exhibited good catalytic activity for the polymerization of ?-caprolactone. All of the obtained polymers have high molecular weights and relatively narrower PDIs. The polymers generated by 2 possessed polydispersity close to 1.1. The good catalytic activities of 1 and 2 reveal their potential applications in polymer industry.  相似文献   

8.
《结构化学》2020,39(6):1103-1111
Two novel macrocyclic Schiff base complexes [LnL(PhCOO)(CH_3OH)](ClO_4)_2·(CH_3OH)_2(Ln =Ho, 1; Ln = Er, 2), in which L denotes the macrocyclic ligand, were synthesized via condensation of 2,6-diformyl-4-methyl-phenol and 1,3-diamino-2-propanol by employing benzoate as the second ligand. Their crystal structures were determined by X-ray diffraction, which showed that both complexes belong to a monoclinic system with space group P2_(1/c). The coordination polyhedron displayed a distorted bicapped trigonal prism with the coordination number of eight. Both complexes efficiently cleaved supercoiled DNA to its nicked circular form. The UV-vis absorption results and ethidium bromide(EB) fluorescence spectra indicated that the complexes bind to CT-DNA in an intercalative mode, with K_(sq) values to be 11830 and 10560, respectively.  相似文献   

9.
A series of mono-and binuclear Co(II) complexes(Co1–Co7) supported by quinoline-2-imidate ligands were synthesized and thoroughly characterized.Measured by single crystal X-ray crystallography,complexes Co1 and Co3 adopted distorted tetrahedral structures around the cobalt center.Upon activation by ethylaluminium sesquichloride(EASC),these cobalt complexes exhibited high catalytic activity and cis-1,4-selectivity towards 1,3-butadiene polymerization.The effects of ligand environment,polymerization temperature,and cocatalyst types on the polymerization were investigated in detail.Interestingly,the binuclear Co(II) complexes exhibited high thermal stability,and the polymer yields were up to 97.2% even at a high temperature of 70 °C.  相似文献   

10.
The reactions of transition metal salts with taurine 5‐chlorosalicylaldelyde Schiff base gave two complexes [Ni(TCSSB)(H2O)3].H2O (1) and [Cu(TCSSB)(H2O)2]2[Cu(TCSSB)2].6H2O (2) (TCSSB=taurine‐5‐chlorosalicylaldelyde Schiff base), which were characterized by elemental analysis and X‐ray diffraction analysis. The complex 1 crystallized in monoclinic system with space group P2 1/c, and a=1.4816(2) nm, b=1.3953(2) nm, c= 0.7466(1) nm, β= 100.499(3)°, V=1.5176(4) nm3, Z=4, and an infinite 3‐D network structure was formed by hydrogen bonds among sulfo group, crystal water and coordinated water. Complex 2 crystallized in triclinic system with space group P1 , with the cell parameters: a = 0.6413(2) nm, b= 1.4596(3) nm, c= 1.6188(4) nm, a= 102.473(5)°, β= 98.979(4)°, γ=101.739°, V=1.4165(6) nm3, Z=1. The coordination environment between Cu(1) and Cu(2) is different. Cu(1) is slightly distorted square pyramidal while Cu(2) is distorted square‐plane. The complex 1 is mononuclear while the complex 2 is made up of two coordinated subunits, namely [Cu(TCSSB)2] and [CU(TCSSB)(H2O)2]2. Besides that the TG‐DTG of the complex 1 was analyzed, the thermal decomposition reaction of the complex was studied under a non‐isothermal condition by TG‐DTG. The TG and DTG curves indicate that the complex was decomposed in three stages: .  相似文献   

11.
Two new mononuclear complexes, namely [Co(L)_2](1) and [Mn(L)_2](2)(HL = N-(3-methylsalicylidene)tryptamine), have been synthesized by the reactions of the ligand with cobalt acetate or manganese acetate in anhydrous ethanol. The crystal structures of the complexes were characterized by IR spectrum, elemental analysis, PXRD and single-crystal X-ray diffraction analysis. Complex 1 crystallizes in monoclinic, space group C2/c, with a = 23.146(2), b = 9.4864(10), c = 13.9261(15) ?, β = 102.898(2)°, V = 2980.6(5) ?3, Z = 4, Dc = 1.367 g/cm3, F(000) = 1284 and μ = 0.616 mm-1. Complex 2 crystallizes in monoclinic, space group P21/n, with a = 14.807(11), b = 13.118(10), c = 16.663(13) ?, β = 111.237(14)°, V = 3017(4) ?3, Z = 4, Dc = 1.342 g/cm~3, F(000) = 1276 and μ = 0.477 mm-1. The units of complex 1 are linked by intermolecular N–H···π hydrogen bonds into infinite 1D chains, which are further extended into a 3D supramolecular structure by a series of π···π stacking interactions. The units of complex 2 are linked by intermolecular N–H···π hydrogen bonds and C–H···π hydrogen bonds into an infinite 3D supramolecular structure. Meanwhile, the antibacterial activities of the ligand and its complexes have been tested against four kinds of bacteria. The results show that the three compounds all have excellent antibacterial activities and that 1 and 2 possess stronger inhibiting effects against the bacteria than the Schiff base.  相似文献   

12.
Two new zinc(Ⅱ) complexes, [Zn2L2aCl4]·2[ZnL(CH3OH)Cl2] 1 and [ZnL2(NO3)2] 2,were synthesized by reacting ZnX2·nH2O (X = Cl-, NO3-) and a Schiff base ligand 2-[(4-me-thylphenylimino)methyl]-6-methoxyphenol (C15H15NO2, L) which was obtained by the condensation of o-vanillin (2-hydroxy-3-methoxybenzaldehyde) with p-toluidine. Both 1 and 2 were characterized by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis,1H-NMR spectra and thermogravimetric analysis. The Schiff base ligand and its zinc(Ⅱ) complexes have been tested in vitro to evaluate their antibacterial activity against bacteria, viz., Escherichia Coli,Staphylococcus aureus and Bacillus Subtilis. The results show that these complexes have higher activity than the corresponding free Schiff base ligand against the same bacteria.  相似文献   

13.
Spin transition compounds are of great interest because of their potential application in molecular based electronic devices such as optical memoty and switch, display and data record[1]. The occurrence of iron(Ⅱ) spin crossover systems depends on the ligand field strength. Iron(Ⅱ) spin crossover compounds mainly have sixfold nitrogen coordination and the range of lODq is very narrow:10DqHS≈11500-12500 cm-1 and 10DqLS≈19000-21000 cm-1[2]. The sensitivity of the spin state to small perturbations suggests that new coordination complexes exhibiting spin transition phenomena could be designed through a fine tuning of the ligands surrounding the metal. The derivatives of 1,2,4-triazole have been found to generate an intermediate ligand field force and the iron(Ⅱ) compounds containing such ligands which yielded spin-crossover materials exhibiting cooperative behavior have been reported recently[3]. In this paper we present two new iron(Ⅱ) compounds FeL3(ClO4)2·2H2O (1) and FeL3(BF4)2·3H2O (2),where L is the Schiff base ligand derived from 4-amino-l,2,4-triazole and benzaldehyde. The compounds appear as white (HS) powders at room temperature and the color changes to pink (LS) upon decreasing the temperature to liquid nitrogen. 1 and 2 are investigated by the optical setup (520 nm, 293-77 K), 57Fe Mössbauer Spectroscopy (293-77 K) and magnetic susceptibility (293-4 K). The HS→LS and LS→HS transitions were observed at Tc↓=135 K (1) and 169 K (2), and Tc↑=150 K (1) and 180 K (2), respectively. The thermal hysteresis is found to be 15 K and 11 K for 1 and 2. The area fractions are calculated to be 57% for 1 and 43% for 2. Variable temperature magnetic susceptibility data were fitted to magnetic susceptibility equations derived from domain model, two level Ising-type model and regular solution model. The calculated variations of enthalpy and entropy of the compounds fall within the limits ΔH≈8.1-10.9 kJ·mol-1 and ΔS≈47-61 J·K-1·mol-1 found for mononuclear iron(Ⅱ) spin transition compounds from calorimetric measurements. The cooperativity parameter y determines the occurrence of hysteresis.  相似文献   

14.
New complexes of iron(II) chloride and bromide with 1,2,4-triazole (Htrz) and 4-amino-1,2,4-tri-azole (NH2trz) of composition Fe(Htrz)3Cl2 · 1.5H2O, Fe(NH2trz)3Cl2 · 2H2O, Fe(Htrz)3Br2 · 2H2O, and the Fe(NH2trz)3SO4 · H2O complex were synthesized and studied by magnetochemical, electronic, IR and Mössbauer spectroscopy methods. Magnetochemical studies showed that these complexes exhibit 1 A 1 5 T 2 spin transition accompanied by thermochromism (a reversible pink white change of color).  相似文献   

15.
Three lanthanide(III) complexes [Ln(4-NCP)(1,4-BDC)]n·xn H2O(Ln = Pr(1), Sm(2), Nd(3). 4-HNCP = 2-(4-carboxyphenyl)imidazo(4,5-f)(1,10)phenanthroline, 1,4-H2 BDC = benzene-1,4-dicarboxylic acid) have been hydrothermally synthesized and characterized via elemental analysis, infrared spectrometry and single-crystal X-ray diffraction. Structural analyses revealed that complexes 1~3 possess similar porous three-dimensional frameworks with the point symbol {4~(12)·6~3}. Meanwhile, complexes 1~3 exhibit excellent thermal stabilities and complex 2 exhibits characteristic luminescent property.  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 P2_12_12 with Z=4. For 1,α= 12.082(2),b = 15.447(3),c = 18.784(4)(A),V= 3505.7(12) (A)~3,M_r = 731.50,D_c = 1.386 g/cm~3,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,α=12.181(2),b=15.501(3),c=18.877(4)(A),V= 3564.3(12)(A)~3,M_r=736.33,Dc = 1.372 g/cm~3,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> 20(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.
Two novel cobalt(Ⅱ) compounds were obtained and characterized by X-ray sing- le-crystal diffraction, IR, 1H NMR and elemental analysis. Compound 1 crystallizes in monoclinic, space group P21/n, with a = 18.046(4), b = 11.335(3), c = 19.157(5)A, β = 92.707(3)°, Z = 4, V = 3914.4(16) A3, Mr = 968.56, Dc = 1.644 g/cm3, μ = 1.378 mm^-1, F(000) = 1960, the final R = 0.0367 and wR = 0.0895. The crystal of compound 2 is of monoclinic, space group P211c with a = 8.7253(10), b = 10.9031(13), c = 18.235(2)A,β = 93.2210(10)°, Z = 4, V = 1732.0(3)A3, Mr = 464.21, Dc = 1.780 g/cm3,μ = 1.560 mm-1, F(000) = 932, the final R = 0.0322 and wR = 0.0743.  相似文献   

18.
Three new Schiff bases, -(bis(pyridin-2-yl)alkylidene)butane-1,4-diamine [(py)(R)C=N-(CH)N=C(R)(py), L: py = pyridine; R = H, -(bis(pyridin-2-yl)formylidene)butane-1,4-diamine (bpfd); R = Me, -(bis(pyridin-2-yl)methylidene)butane-1,4-diamine (bpmd); R = C, -(bis(pyridin-2-yl)bezylidene)butane-1,4-diamine (bpbd)] were prepared and used to synthesize six dinuclear cadmium(II)azido complexes of type [Cd(L)(N)](Y) [L = bpfd, Y = ClO (1a); L = bpfd, Y = PF (1b); L = bpmd, Y = ClO (2a); L = bpmd, Y = PF (2b); L = bpbd, Y = ClO (3a); and L = bpbd, Y = PF (3b)]. Two representative members of the series, 3a and 3b, have been characterized by single crystal X-ray diffraction measurements. Structural study reveals that each cadmium center in both dinuclear compounds is located in a distorted octahedral coordination environment surrounded by six nitrogen atoms—four (N1, N2, N3, N4) from tetradentate ligand, and the fifth and sixth positions occupied by nitrogen atoms (N5, N5*) of doubly end-on bridging azides. The complexes display intraligand 1 fluorescence and intraligand 3 phosphorescence in glassy solutions (MeOH at 77 K).  相似文献   

19.
Four dinuclear amino acid cadmium(Ⅱ) complexes [Cd2(tren)2(dl-alaninato)](ClO4)3·H2O(Ⅰ), [Cd2(tren)2·(l-alaninato)](ClO4)3·H2O(Ⅱ), [Cd2(tren)2(dl-phenylalaninato)](ClO4)3(Ⅲ) and [Cd2(tren)2(l-phenylalaninato)]· (ClO4)3(Ⅳ), constructed from mixed ligands of tris(2-aminoethyl)amine(tren) and racemic or natural amino acids( amino acids=dl- or l-alanine, and dl- or l-phenylalanine), have been synthesized and characterized by X-ray crystallography. The structural analysis of complexes Ⅰ and Ⅲ reveals that the cadmium centers are coordinated by one tren ligand and one amino acid molecule with the unusual (N,O,O′)-bridged mode, resulting in asymmetric chromophores of CdN4O and CdN5O in complex Ⅰ, CdN4O2 and CdN5O in complex Ⅲ, respectively. The utility of the four complexes as efficient water-compatible Lewis acid catalysts for the direct aldol reaction in water was examined. The reaction proceeded smoothly to afford the corresponding β-hydroxy ketones in up to 99% yield. Moreover, the diastereoselectivity of the reaction favors the formation of the syn-isomers.  相似文献   

20.
A homochiral complex, Zn3(Hsalen)2(Py)4(H2O)2 (salen = (1R,2R)-(-)-diamino-cyclohexane-N,N'-biscarboxyl-salicylidene) 1, has been synthesized by solvothermal procedure and characterized by IR, microanalysis, TGA, powder and single-crystal X-ray crystallography. It crystallizes in monoclinic space group P2 with a = 10.9439(7), b = 10.1722(6), c = 27.3450(17), β = 97.5060(10)o, V = 3018.1(3) 3, Z = 2, Zn3(Hsalen)2(Py)4(H2O)2, Mr = 1363.33, Dc = 1.500 g/cm3, F(000) = 1408, μ = 1.257 mm-1, GOOF = 1.042, the final R = 0.0601 and wR = 0.1464 for 10322 observed reflections with I 2σ(I). The coordination polymer 1 possesses a 1D infinite zigzag chain architecture constructed by strong hydrogen bonding interactions and the polymeric chains are further assembled into a 2D supramolecular network structure via C-H···π interactions between the cyclohexane and aromatic rings of the ligand of adjacent chains. Simultaneously, π···π stacking interactions play an important role in forming the 2D supramolecular framework.  相似文献   

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