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1.
Four new diorganotin(IV) complexes of N‐(5‐halosalicylidene)tryptophane, R2Sn[5‐X‐2‐OC6H3CH?NCH(CH2Ind)COO] [Ind = 3‐indolyl; R, X = Et, Cl ( 1 ); Et, Br( 2 ); n‐Bu, Cl ( 3 ); n‐Bu, Br ( 4 )], were synthesized and characterized by elemental analysis, IR and NMR (1H, 13C and 119Sn) spectra. The crystal structures of complexes 1 – 3 were determined by X‐ray single crystal diffraction and showed that the tin atoms are in a distorted trigonal bipyramidal geometry and form five‐ and six‐membered chelate rings with the tridentate ligand. Intermolecular weak interactions in 1–3 link molecules, respectively, into a two‐dimensional array, a one‐dimensional infinite chain and a one‐dimensional double‐chain supramolecular structure. Bioassay results of the compounds indicated that the dibutyltin complexes 3 and 4 have potent in vitro cytotoxic activity against two human tumor cell lines, CoLo205 and Bcap37, while the diethyltin complexes 1 and 2 display weak cytotoxic activity. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

2.
The preparation and spectroscopic and structural characterization of three ZnII complexes with bis[N‐(2,6‐dimethylphenyl)imine]acenaphthene, L1, and with bis[N‐(2‐ethylphenyl)imine]acenaphthene, L2, are decribed herein. Two of the complexes were prepared from ZnCl2 and the third from Zn(NCS)2. One‐pot reaction techniques were used, leading to high yields. The complexes were characterized by microanalysis, IR and 1H NMR spectroscopy, and single‐crystal X‐ray diffraction. The structures of the complexes are significantly different, with the chloride‐containing species forming distorted tetrahedra around the metal, whereas its thiocyanate analog is dimeric, with each metal at the center of a distorted square pyramid, with bridging and terminal [SCN] ligands.  相似文献   

3.
A new one‐dimensionally neutral coordination polymer, namely {[Pb(phen)2(ox)]·5H20}n (phen = 1, 10‐phenanthroline, ox = oxalate) ( 1 ), has been synthesized under hydrothermal condition and characterized by X‐ray crystallography. Complex 1 crystallizes in the orthorhombic space group Pban (No. 50) with a = 19.358(2), b = 6.8135(6), c = 9.7015(8)Å, V = 1279.6(2)Å3, and Z = 2. Each Pb(II) atom is eight‐coordinated in a square‐antiprismatic D4d geometry by four nitrogen atoms from two phen groups and four oxygen atoms from two ox ligands. The polymeric chains further constructed into a three‐dimensional network via strong π—π stacking interactions and hydrogen bonds. The complex exhibits intense blue photoluminescence with an emission maximum at 403 nm at room temperature.  相似文献   

4.
The reaction of [1,3‐bis(2‐ethoxy)benzene]triazene, [ HL ], with Hg(SCN)2 and Hg(CH3COO)2, resulted in the formation of the complexes [Hg L (SCN)] ( 1 ) and [Hg L 2] · CH3OH ( 2 ). They were characterized by means of X‐ray crystallography, CHN analysis, FT‐IR, 1H NMR, and 13C NMR spectroscopy. The structure of compound 1 consists of two independent complexes in which the HgII atoms are stacked along the crystallographic a axis to form infinite chains. Each HgII atom is chelated by one L ligand and one SCN ligand, whereas in compound 2 , the HgII atom is surrounded by two L ligands. In addition, 1D chains formed by metal–π interactions are connected to each other by C–H ··· π stacking interactions in the structure of 1 , which results in a 2D architecture. An interesting feature of compound 2 is the presence of C–H ··· π edge‐to‐face interactions.  相似文献   

5.
Semirigid organic ligands can adopt different conformations to construct coordination polymers with more diverse structures when compared to those constructed from rigid ligands. A new asymmetric semirigid organic ligand, 4‐{2‐[(pyridin‐3‐yl)methyl]‐2H‐tetrazol‐5‐yl}pyridine ( L ), has been prepared and used to synthesize three bimetallic macrocyclic complexes and one coordination polymer, namely, bis(μ‐4‐{2‐[(pyridin‐3‐yl)methyl]‐2H‐tetrazol‐5‐yl}pyridine)bis[dichloridozinc(II)] dichloromethane disolvate, [Zn2Cl4(C12H10N6)2]·2CH2Cl2, ( I ), the analogous chloroform monosolvate, [Zn2Cl4(C12H10N6)2]·CHCl3, ( II ), bis(μ‐4‐{2‐[(pyridin‐3‐yl)methyl]‐2H‐tetrazol‐5‐yl}pyridine)bis[diiodidozinc(II)] dichloromethane disolvate, [Zn2I4(C12H10N6)2]·2CH2Cl2, ( III ), and catena‐poly[[[diiodidozinc(II)]‐μ‐4‐{2‐[(pyridin‐3‐yl)methyl]‐2H‐tetrazol‐5‐yl}pyridine] chloroform monosolvate], {[ZnI2(C12H10N6)]·CHCl3}n, ( IV ), by solution reaction with ZnX2 (X = Cl and I) in a CH2Cl2/CH3OH or CHCl3/CH3OH mixed solvent system at room temperature. Complex ( I ) is isomorphic with complex ( III ) and has a bimetallic ring possessing similar coordination environments for both of the ZnII cations. Although complex ( II ) also contains a bimetallic ring, the two ZnII cations have different coordination environments. Under the influence of the I? anion and guest CHCl3 molecule, complex ( IV ) displays a significantly different structure with respect to complexes ( I )–( III ). C—H…Cl and C—H…N hydrogen bonds, and π–π stacking or C—Cl…π interactions exist in complexes ( I )–( IV ), and these weak interactions play an important role in the three‐dimensional structures of ( I )–( IV ) in the solid state. In addition, the fluorescence properties of L and complexes ( I )–( IV ) were investigated.  相似文献   

6.
The tris(2,4‐dimethylpentadienyl) complexes [Ln(η5‐Me2C5H5)3] (Ln = Nd, La, Y) are obtained analytically pure by reaction of the tribromides LnBr3·nTHF with the potassium compound K(Me2C5H5)(thf)n in THF in good yields. The structural characterization is carried out by X‐ray crystal structure analysis and NMR‐spectroscopically. The tris complexes can be transformed into the dimeric bis(2,4‐dimethylpentadienyl) complexes [Ln2(η5‐Me2C5H5)4X2] (Ln, X: Nd, Cl, Br, I; La, Br, I; Y, Br) by reaction with the trihalides THF solvates in the molar ratio 2:1 in toluene. Structure and bonding conditions are determined for selected compounds by X‐ray crystal structure analysis and NMR‐spectroscopically in general. The dimer‐monomer equilibrium existing in solution was investigated NMR‐spectroscopically in dependence of the donor strength of the solvent and could be established also by preparation of the corresponding monomer neutral ligand complexes [Ln(η5‐Me2C5H5)2X(L)] (Ln, X, L: Nd, Br, py; La, Cl, thf; Br, py; Y, Br, thf). Finally the possibilities for preparation of mono(2,4‐dimethylpentadienyl)lanthanoid(III)‐dibromid complexes are shown and the hexameric structure of the lanthanum complex [La6(η5‐Me2C5H5)6Br12(thf)4] is proved by X‐ray crystal structure analysis.  相似文献   

7.
Two new trinuclear complexes [CuII(NiIIX1)2(C2H5OH)2]· (ClO4)2·2(CH3OH) ( 1 ) and [CuII(NiIIX2)2(H2O)]·(ClO4)2· 0.75(H2O) ( 2 ) (X1 = dianion of 5,6;13,14‐dibenzo‐7,12‐bis(ethoxycarboxyl)‐9‐methyl‐2,3‐dioxo‐1,4,8,11‐tetraazacyclotetradeca‐7,11‐diene. X2 = dianion of 5,6;13,14‐dibenzo‐9,10‐cyclohexano‐7,12‐bis(ethoxycarboxyl)‐2,3‐dioxo‐1,4,8,11‐tetraazacyclotetradeca7,11‐diene.) have been synthesized and characterized by single crystal X‐ray analysis, elemental analysis, IR, UV and EPR spectroscopies. The complexes consist of NiIICuIINiII heteronuclear cationic entities. The central CuII atom of 1 lies in an octahedral coordination environment, while that of 2 resides in a square‐pyramidal coordination sphere. The adjacent trinuclear units of 1 are linked together through π‐π stacking interactions resulting in a 1D supramolecular chain, whereas the π‐π stacking interactions between the contiguous units of 2 lead to a 2D structure. The EPR spectra of the two complexes show a signal of an axially elongated octahedral CuII system in 1 and an axially elongated square‐pyramidal CuII system in 2 , respectively. The hyperfine splitting of the CuII atoms (ICu = 3/2) has also been observed in the EPR spectra.  相似文献   

8.
Series of typical π‐type and pseudo‐π‐type halogen‐bonded complexes B ··· ClY and B ··· BrY and hydrogen‐bonded complex B ··· HY (B = C2H4, C2H2, and C3H6; Y = F, Cl, and Br) have been investigated using the MP2/aug‐cc‐pVDZ method. A striking parallelism was found in the geometries, vibrational frequencies, binding energies, and topological properties between B ··· XY and B ··· HY (X = Cl and Br). It has been found that the lengths of the weak bond d(X ··· π)/d(H ··· π), the frequencies of the weak bond ν(X ··· π)/ν(H ··· π), the frequency shifts Δν(X? Y)/Δν(H? Y), the electron densities at the bond critical point of the weak bonds ρc(X ··· π)/ρc(H ··· π), and the electron density changes Δρc(X? Y)/Δρc(H? Y) could be used as measures of the strengths of typical π‐type and pseudo‐π‐type halogen/hydrogen bonds. The typical π‐type and pseudo‐π‐type halogen bond and hydrogen bond are noncovalent interactions. For the same Y, the halogen bond strengths are in the order B ··· ClY < B ··· BrY. For the same X, the halogen bond strength decreases according to the sequence F > Cl > Br that is in agreement with the hydrogen bond strengths B ··· HF > B ··· HCl > B ··· HBr. All of these typical π‐type and pseudo‐π‐type hydrogen‐bonded and halogen‐bonded complexes have the “conflict‐type” structure. Contour maps of the Laplacian of π electron density indicate that the formation of B ··· XY halogen‐bonded complex and B ··· HY hydrogen‐bonded complex is very similar. Charge transfer is observed from B to XY/HY and both the dipolar polarization and the volume of the halogen atom or hydrogen atom decrease on B ··· XY/B ··· HY complex formation. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011  相似文献   

9.
Two CoII complexes, Co(phen)(HL)2 ( 1 ) and [Co2(phen)2(H2O)4L2]·H2O ( 2 ) (H2L = HOOC‐(CH2)5‐COOH), were synthesized and structurally characterized on the basis of single crystal X‐ray diffraction data. In complex 1 the Co atoms are tetrahedrally coordinated by two N atoms of one phen ligand and two O atoms of different hydrogenpimelato ligands. Through π—π stacking interactions between carboxyl group and phen ligand, the complex molecules are assembled into 1D columnar chains, which are connected by intermolecular hydrogen bonds. Complex 2 consists of the centrosymmetric dinuclear [Co2(phen)2(H2O)4L2] molecules and hydrogen bonded H2O molecules. The Co atoms are each octahedrally surrounded by two N atoms of one phen ligand and four O atoms from two bis‐monodentate pimelato ligands and two H2O molecules at the trans positions. The results about thermal analyses, which were performed in flowing N2 atmosphere, on both complexes were discussed. Crystal data: ( 1 ) C2/c (no. 15), a = 13.491(1)Å, b = 9.828(1)Å, c = 19.392(2)Å, β = 100.648(1)°, U = 2526.9(4)Å3, Z = 4; ( 2 ) P1 (no. 2), a = 11.558(1)Å, b = 11.947(3)Å, c = 15.211(1)Å, α = 86.17(1)°, β = 75.55(1)°, γ = 69.95(1)°, U = 1910.3(3)Å3, Z = 2.  相似文献   

10.
Noncovalent halogen/π interactions of FCl with substituted benzenes have been investigated using ab initio calculations. It was shown that the predicted maximum interaction energy gap between the substituted and unsubstituted systems amounts to 1.14 kcal/mol, and therefore substituents on benzene have a pronounced effect on the strength of halogen/π interactions. While the presence of electron‐donating groups (NH2, CH3, and OH) on benzene enhances the interaction energy appreciably, an opposite effect is observed for electron‐accepting groups (NO2, CN, Br, Cl, and F). The large gain of the attraction by electron correlation illustrates that the stabilities of the systems considered arise primarily from the dispersion interaction. Beside the dispersion interaction, the charge‐transfer interaction also plays an important role in halogen/π interactions, as a charge density analysis suggested. To provide more insight into the nature of halogen/π interactions, topological analysis of the electron density distribution and properties of bond critical points were determined in terms of the atoms in molecules (AIM) theory. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007  相似文献   

11.
A new mixed oxaaza‐macrocyclic ligand, L1, has been obtained by direct synthesis between 1,4‐bis‐(2′‐formylphenyl)‐1,4‐dioxabutane and the diamine 2,2′‐ethylenedioxydiethylamine. The dialkylated ligand L2, bearing two nitrobenzyl pendant groups, has been prepared and transitional, post‐transitional and Ca2+, Sr2+, and Ba2+ metal complexes have been synthesized in order to elucidate the coordination preferences. The crystal structures of the ligands L1 and L2 and the complexes [SrL2(H2O)2](ClO4)2 and [BaL2(NCS)2(CH3CN)]·CH3CN have been determined by single crystal X‐ray diffraction. The structures reveal the presence of mononuclear endomacrocyclic complexes where the pendant arms radiate away from the ligand.  相似文献   

12.
Three multinuclear Cu (II), Zn (II) and Cd (II) complexes, [Cu2(L)(μ‐OAc)]·CHCl2 ( 1 ), [Zn2(L)(μ‐OAc)(H2O)]·3CHCl3 ( 2 ) and [{Cd2(L)(OAc)(CH3CH2OH)}2]·2CH3CH2OH ( 3 ) with a single‐armed salamo‐like dioxime ligand H3L have been synthesized, and characterized by FT‐IR, UV–vis, X‐ray crystallography and Hirshfeld surfaces analyses. The ligand H3L has a linear structure and C‐H···π interactions between the two molecules. The complex 1 is a dinuclear Cu (II) complex, Cu1 and Cu2 are all five‐coordinate possessing distorted square pyramidal geometries. The complex 2 also forms a dinuclear Zn (II) structure, and Zn1 and Zn2 are all five‐coordinate bearing distorted trigonal bipyramidal geometries. The complex 3 is a symmetrical tetranuclear Cd (II) complex, and Cd1 is a hexa‐coordinate having octahedral configuration and Cd2 is hepta‐coordinate with a pentagonal bipyramidal geometry, and it has π···π interactions inside the molecule. In addition, fluorescence properties of the ligand and its complexes 1 – 3 have also been discussed.  相似文献   

13.
Fourteen new diorganotin(IV) complexes of N‐(5‐halosalicylidene)‐α‐amino acid, R′2Sn(5‐X‐2‐OC6H3CH?NCHRCOO) (where X = Cl, Br; R = H, Me, i‐Pr; R′ = n‐Bu, Ph, Cy), were synthesized by the reactions of diorganotin halides with potassium salt of N‐(5‐halosalicylidene)‐α‐amino acid and characterized by elemental analysis, IR and NMR (1H, 13C and 119Sn) spectra. The crystal structures of Bu2Sn(5‐Cl‐2‐OC6H3CH?NCH(i‐Pr)COO) and Ph2Sn(5‐Br‐2‐OC6H3CH?NCH(i‐Pr)COO) were determined by X‐ray single‐crystal diffraction and showed that the tin atoms are in a distorted trigonal bipyramidal geometry and form five‐ and six‐membered chelate rings with the tridentate ligand. Bioassay results of a few compounds indicated that the compounds have strong cytotoxic activity against three human tumour cell lines, i.e. HeLa, CoLo205 and MCF‐7, and the activity decreased in the order Cy>n‐Bu>Ph for the R′ group bound to tin. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   

14.
Two new mixed‐anion zinc(II) and cadmium(II) complexes of 3‐(2‐pyridyl)‐5,6‐diphenyl‐1,2,4‐triazine (PDPT) ligand, [Zn(PDPT)2Cl(ClO4)] and [Cd(PDPT)2(NO3)(ClO4)], have been synthesized and characterized by elemental analysis, IR‐ and 1H NMR spectroscopy. The single crystal X‐ray analyses show that the coordination number in these complexes is six with four N‐donor atoms from two “PDPT” ligand and two of the anionic ligands, ZnN4ClOperchlorate, CdN4OnitrateOperchlorate. Self‐assembly of these compounds in the solid state via ππ‐stacking interactions is discussed.  相似文献   

15.
A novel dinuclear bismuth(III) coordination compound, [Bi2(C7H3NO4)2(N3)2(C12H8N2)2]·4H2O, has been synthesized by an ionothermal method and characterized by elemental analysis, energy‐dispersive X‐ray spectroscopy, IR, X‐ray photoelectron spectroscopy and single‐crystal X‐ray diffraction. The molecular structure consists of one centrosymmetric dinuclear neutral fragment and four water molecules. Within the dinuclear fragment, each BiIII centre is seven‐coordinated by three O atoms and four N atoms. The coordination geometry of each BiIII atom is distorted pentagonal–bipyramidal (BiO3N4), with one azide N atom and one bridging carboxylate O atom located in axial positions. The carboxylate O atoms and water molecules are assembled via O—H...O hydrogen bonds, resulting in the formation of a three‐dimensional supramolecular structure. Two types of π–π stacking interactions are found, with centroid‐to‐centroid distances of 3.461 (4) and 3.641 (4) Å.  相似文献   

16.
The intermolecular interactions existing at three different sites between phenylacetylene and LiX (X = OH, NH2, F, Cl, Br, CN, NC) have been investigated by means of second‐order Møller?Plesset perturbation theory (MP2) calculations and quantum theory of “atoms in molecules” (QTAIM) studies. At each site, the lithium‐bonding interactions with electron‐withdrawing groups (? F, ? Cl, ? Br, ? CN, ? NC) were found to be stronger than those with electron‐donating groups (? OH and ? NH2). Molecular graphs of C6H5C?CH···LiF and πC6H5C?CH···LiF show the same connectional positions, and the electron densities at the lithium bond critical points (BCPs) of the πC6H5C?CH···LiF complexes are distinctly higher than those of the σC6H5C?CH···LiF complexes, indicating that the intermolecular interactions in the C6H5C?CH···LiX complexes can be mainly attributed to the π‐type interaction. QTAIM studies have shown that these lithium‐bond interactions display the characteristics of “closed‐shell” noncovalent interactions, and the molecular formation density difference indicates that electron transfer plays an important role in the formation of the lithium bond. For each site, linear relationships have been found between the topological properties at the BCP (the electron density ρb, its Laplacian ?2ρb, and the eigenvalue λ3 of the Hessian matrix) and the lithium bond length d(Li‐bond). The shorter the lithium bond length d(Li‐bond), the larger ρb, and the stronger the π···Li bond. The shorter d(Li‐bond), the larger ?2ρb, and the greater the electrostatic character of the π···Li bond. © 2012 Wiley Periodicals, Inc.  相似文献   

17.
Despite the large number of reported crystalline structures of coordination complexes bearing pyridines as ligands, the relevance of π–π interactions among these hereroaromatic systems in the stabilization of their supramolecular structures and properties is not very well documented in the recent literature. The title compound, [CoCl2(C5H6N2)2], was obtained as bright‐blue crystals suitable for single‐crystal X‐ray diffraction analysis from the reaction of 4‐aminopyridine with cobalt(II) chloride in ethanol. The new complex was fully characterized by a variety of spectroscopic techniques and single‐crystal X‐ray diffraction. The crystal structure showed a tetrahedral complex stabilized mainly by bidimensional motifs constructed by π–π interactions with large horizontal displacements between the 4‐aminopyridine units, and N—H…Cl hydrogen bonds. Other short contacts, such as C—H…Cl interactions, complete the three‐dimensional arrangement. The supramolecular investigation was extended by statistical studies using the Cambridge Structural Database and a Hirshfeld surface analysis.  相似文献   

18.
Two copper(I)‐based frameworks of complexes {[Cu(L)2(ClO4)]?CH3CN}( 2 ) and {[Cu(L)(ClO4)]? 2CH3CN} ( 3 ) (L = 1,3,5‐tris(4‐pyridylethynyl) benzene) were produced by reacting [Cu(MeCN)4(ClO4)] with different amounts of a ligand (L) using a hydrothermal method at temperatures of up to 130°C. The nitrogen atoms in the pyridine moieties of the ligand coordinate to the Cu(I) ion. The charge on the Cu(I) ion can be stabilized by extending the degree of conjugation in the system and by taking advantage of its highly symmetrical structure. The large degree of conjugation also supports numerous π–π interactions in the framework.  相似文献   

19.
Using ferrocenecarboxylic acid (FcCOOH) as organometallic ligand in the synthesis of heterometallic complexes led to the isolation of the compound [(FcCOO)Cu(bpy)2](BF4) · bpy · CH3OH. It was characterized by IR spectroscopy, EA, powder XRD, UV, and TGA measurements. Single‐crystal X‐ray structural analysis revealed that a unique 2D supramolecular network purely formed by aromatic π ··· π stacking interactions was observed, namely, {[(FcCOO)Cu(bpy)2](BF4) · bpy · CH3OH} ( 1 ). The solid UV/Vis diffuse reflectance spectrum revealed the optical energy gap of 1 to be 3.54 eV, which is dramatically blue shifted compared with the value of ferrocene. Experimental results of thermal analysis and electrochemical analysis show that 1 has good thermal and better electrochemical stability.  相似文献   

20.
The preparation and characterization of two novel HgCl2 and Hg(SCN)2 complexes with bis[N‐(2‐tert‐butylphenyl)imine]acenaphthene is here described. One‐pot reaction techniques were used, leading to high yields of 75 % and 81 %, respectively. The complexes were characterized by microanalysis, i.r. and 1HNMR spectroscopy, and by single crystal X‐ray diffraction. The structures of the complexes present similar characteristics, the most outstanding being the formation of dimers via intermolecular interaction. Whereas the HgCl2 complex shows a unidimensional network due to strong π–π interactions, its Hg(SCN)2 counterpart displays a supramolecular arrangement resulting from non classical hydrogen bond formation.  相似文献   

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