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1.
Four novel Schiff base nickel(II) and copper(II) complexes, derived from the end‐on (μ1,1‐N3) azide, end‐to‐end (μ1,3‐NCS) thiocyanate, or phenolate oxygen bridges, have been synthesized and their crystal structures determined by X‐ray diffraction methods. They are the dinuclear double end‐on azide‐bridged [Ni2(L1)2(MeCN)2(μ1,1‐N3)2]·MeOH ( 1 ), the dinuclear double end‐on azide‐bridged [Ni2(L2)2(MeOH)2(μ1,1‐N3)2][Ni2(L2)2(OH2)2(μ1,1‐N3)2]·MeOH ( 2 ), the dinuclear double end‐to‐end thiocyanate‐bridged [Cu2(L3)2(μ1,3‐NCS)2] ( 3 ), and the dinuclear double phenolate O‐bridged [Cu2(L4)2(NCS)2] ( 4 ), where HL1, HL2, HL3 and HL4 are four tridentate Schiff bases obtained by the condensation of 3,5‐dibromosalicylaldehyde with N‐ethylethane‐1,2‐diamine, of 3,5‐dichlorosalicylaldehyde with N‐methylpropane‐1,3‐diamine, of 3‐bromo‐5‐chlorosalicylaldehyde with 2‐aminomethylpyridine, and of 5‐nitrosalicylaldehyde with 2‐aminomethylpyridine, respectively. Each nickel(II) atom in 1 and 2 is in an octahedral coordination, while each copper(II) atom in 3 and 4 is in a square pyramidal coordination. There exists crystallographic inversion centre symmetry in each of the complexes.  相似文献   

2.
A new tridentate pyridyl Schiff base, N-isopropyl-N′-(1-pyridin-2-ylethylidene)ethane-1,2-diamine (L), was used to synthesize two dinuclear cadmium(II) complexes, [Cd2L2(μ 1,1-N3)2(N3)2] (1) and [Cd2L2(μ 1,3-NCS)2(NCS)2] (2). X-ray single crystal structure determination reveals that in both centrosymmetric complexes, the Cd atom is in a distorted octahedral coordination. In the crystal structures of 1 and 2, the dinuclear cadmium(II) complex molecules are linked, respectively, through intermolecular N–H···N and N–H···S hydrogen bonds to form infinite 1D chains. The preliminary fluorescence properties of the complexes were investigated.  相似文献   

3.
Three novel thiocyanato‐bridged polynuclear cadmium(II) complexes, [Cd(HL1)(NCS)2(μ1,3‐NCS)]n ( 1 ), [CdL2(μ1,3‐NCS)2]n ( 2 ), and [CdL3(μ1,3‐NCS)2]n ( 3 ) (L1 = N‐methyl‐N′‐(1‐pyridin‐2‐ylmethylidene)ethane‐1,2‐diamine, L2 = 2‐(cyclopropyliminomethyl)‐6‐methoxyphenol, L3 = 2‐(cyclopentyliminomethyl)‐6‐methoxyphenol), have been synthesized and structurally characterized by elemental analysis, IR spectra and single‐crystal X‐ray diffraction. Each cadmium(II) atom in the complexes is in an octahedral coordination. The urease inhibitory activities of the complexes were evaluated. All of them showed potent inhibitions against jack bean urease.  相似文献   

4.
A pair of novel azide‐bridged polynuclear copper(II) complexes, [CuL(μ1,1‐N3)]n ( 1 ) and [Cu4L2(CH3COO)21,1‐N3)4] ( 2 ) (L = 4‐chloro‐2‐[(2‐dimethylaminoethylimino)methyl]phenolate), have been obtained from the same Schiff base ligand and an identical synthetic procedure using anions of the metal salts as the only independent variable. Complex 1 was synthesized using copper(II) nitrate, while complex 2 was synthesized using the copper(II) acetate as the salt. Both of the complexes show novel supramolecular structures in their crystals as elucidated by X‐ray analyses. The polynuclear complex 1 contains [CuL(μ1,1‐N3)]n units as the building blocks, crystallizes in the Pbca space group. The tetra‐nuclear complex 2 contains [Cu4L2(CH3COO)21,1‐N3)4] units as the building blocks, crystallizes in the space group.  相似文献   

5.
The title complex, [Cd2(C11H14N3O3)2(NCS)2(CH4O)2], is an inter­esting thio­cyanate‐bridged dinuclear cadmium(II) compound. It is located on a crystallographic inversion center. The CdII atom is six‐coordinated in an octa­hedral configuration by one O and two N atoms of one Schiff base ligand and by the terminal N atom of a bridging thio­cyanate ligand, defining the basal plane, and by the terminal S atom of another bridging thio­cyanate ligand and by the O atom of a coordi­nated methanol mol­ecule, occupying the axial positions. The mol­ecules are linked through inter­molecular O—H⋯O hydrogen bonds, forming chains running along the b axis.  相似文献   

6.
Three new phenolate oxygen bridged transition metal complexes [Zn3(HL1)33‐CH3O)]·(ClO4)2(H2O)3 ( 1 ), [Ni2(HL1)21,1‐N3)(o‐vanillin)]·H2O ( 2 ), [Ni3(HL2)2(PhCOO)2(PhCOOH)2(EtOH)2] ( 3 ) have been synthesized by metal ions and potentially multidentate Schiff base ligands (H2L1 = 2‐((1‐hydroxy‐2‐methylpropan‐2‐ylimino) methyl)‐6‐methoxyphenol; H3L2 = (E)‐1‐((2‐hydroxy‐3‐methoxy‐benzylidene)amino)ethane‐1,2‐diol). All the three complexes 1 , 2 , and 3 have been characterized by elemental analysis, FT‐IR spectroscopy, and single‐crystal X‐ray diffraction studies. Crystal structures reveal that complex 1 is a trinuclear incomplete cubane‐like zinc cluster whereas complex 2 is a dinuclear nickel complex bridged by azide, and compound 3 is a trinuclear nickel complex. The luminescent property for complex 1 and magnetic behaviors for complexes 2 and 3 have been investigated.  相似文献   

7.
The title complex, [Cd2(C13H9Cl2N2O)2(NCS)2]n, is a novel thio­cyanate‐bridged polynuclear cadmium(II) compound. The CdII atom is six‐coordinated in a distorted octa­hedral configuration, with one O and two N atoms of one Schiff base mol­ecule and one terminal S atom of a bridging thio­cyanate ligand defining the equatorial plane, and one terminal N atom of another bridging thio­cyanate ligand and one O atom of another Schiff base mol­ecule occupying axial positions. Adjacent inversion‐related [2,4‐dichloro‐6‐(2‐pyridylmethyl­imino­meth­yl)phenolato]cadmium(II) moieties utilize bridging phenolate and thio­cyanate groups to form polymeric chains running along the b axis.  相似文献   

8.
Two new cadmium(II) complexes, Cd2(L1)2(NCS)2 (1) and Cd2(L2)2(NCS)2 (2), where L1 and L2 are the deprotonated forms of 2-[(3-dimethylaminopropylimino)methyl]-6-ethoxyphenol and 2-methoxy-6-[(pyridin-2-ylmethylimino)methyl]phenol, respectively, have been isolated as crystalline products and characterized by elemental analysis, IR spectroscopy, and single crystal X-ray diffraction method. Both compounds are structurally similar and are phenolate-O-bridged dinuclear cadmium(II) complexes. Each Cd(II) cation in the complexes is octahedrally coordinated. The Cd Cd distances in (1) and (2) are 3.618(2) d 3.571(2)  相似文献   

9.
A copper(II) complex with ethylene diamine and azide, viz., [Cu2(en)2(N3)4]n has been isolated under self-assembling conditions and characterized both structurally and magnetically in order to probe the role of reactant molar ratios in generating supramolecular assemblies with strong magnetic interactions toward achieving molecule-based magnets as a long-term objective. The title structure with ferromagnetic interactions is an intermediate member in the family of copper-azido assemblies involving ethylene diamine, obtained by systematic modifications in the reactant molar ratios, highlighting the inherent difficulty in controlling the final solid formation and potential of the delicate equilibrium conditions in directing supramolecular structures, which may display interesting structure-correlated properties. The structure is a chain of μ-1,1 bridged dimers of Cu2, connected to Cu1 through μ-1,3 azide bridges, leading to a rail-road arrangement of polymeric chains. Two such parallel chains are further linked to each other through Cu3, which is connected to Cu2′ of the dimer, through asymmetric end-on μ-1,1 azide bridges, resulting in a 2-D network in the unit cell. The magnetic behavior revealed ferromagnetic interactions in Cu(II) pairs and is dominated by overall antiferromagnetic interactions within the network.  相似文献   

10.
A pair of azido-bridged Schiff base copper complexes, [CuL1(μ1,3-N3)] n · nClO4 (1) and [Cu2(L2)2(μ 1,1-N3)2] · 2ClO4 (2) (L1 = N,N-diethyl-N′-(1-pyridin-2-ylmethylidene)ethane-1,2-diamine, L2 = N-isopropyl-N′-(1-pyridin-2-ylmethylidene)ethane-1,2-diamine) have been obtained by the same synthetic procedures, but with slightly different Schiff bases. The structures of the complexes have been characterized by IR spectra, elemental analysis, and single crystal X-ray determination. Each Cu atom in the complexes is five-coordinate in a square pyramidal configuration involving the three N atoms of the Schiff base ligand and two N atoms from two bridging azide ligands. The azide ligands adopt end-to-end bridging mode in (1), and end-on bridging mode in (2). The different coordination modes of the azide ligands in the two complexes are assigned to the steric effects of the terminal groups (two ethyl groups for (1) and one isopropyl group for (2)) in the Schiff base ligands. The urease inhibitory activities of the complexes were evaluated. Both of them showed potent inhibition against jack bean urease. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

11.
An end-on azido-bridged dinuclear Cu(II) complex, [Cu2L21,1–N3)2]·CH3OH, and an end-on azido-bridged polynuclear Cu(II) complex, [CuL(μ1,1–N3)]n, derived from the Schiff base 2-[(3-methylaminopropylimino)methyl]phenol (HL), were synthesized and characterized by physico-chemical and spectroscopic methods. The two complexes were synthesized and crystallized with different solvents, methanol for [Cu2L21,1–N3)2]·CH3OH and ethanol for [CuL(μ1,1–N3)]n. The Cu atom in each complex is five-coordinate in a square pyramidal geometry with one O and two N atoms of L, and one N atom of an azide ligand defining the basal plane, and with one N atom of another azide ligand occupying the apical position. The urease inhibitory activities of both complexes were evaluated.  相似文献   

12.
Four Schiff base complexes, [Cu2(L1)2(μ‐NCS)2] ( 1 ), [Cu2(L2)2(μ‐N3)2] ( 2 ), Cu[Cu(CH3COO)(L3)]2 ( 3 ), and [Zn{Zn(C3H4N2)(L3)}2(NO3)](NO3) ( 4 ) (where L1 = 2‐[(pyridin‐2‐ylmethylimino)methyl]phenol, L2 = 1‐[(pyridin‐2‐ylmethylimino)methyl]naphthalen‐2‐ol, and L3 = bis(salicylidene)‐1, 3‐propanediamine), were synthesized and characterized by elemental analyses, infrared spectroscopy, and single crystal X‐ray determinations. Both 1 and 2 are structurally similar di‐nuclear complexes, which are located at crystallographic inversion centers (with the center of the central Cu2N2 ring). In 1 , each copper atom has a slightly distorted square pyramidal configuration, coordinated by two nitrogen atoms and one oxygen atom from L1 and another two terminal nitrogen atoms from two bridging thiocyanate anions. The Cu···Cu separation is 3.466(3) Å. The structure of 2 is similar to that of 1 , with Cu···Cu separation of 3.368(2) Å. Both 3 and 4 are linear tri‐nuclear complexes. In 3 , the central Cu2+ ion is located on an inversion centre and has a distorted octahedral coordination involving four bridging O atoms from two Schiff base ligands (L3) in the equatorial plane and one O atom from each bridging acetate group in the axial positions. The coordination around the terminal Cu2+ ions is irregular‐square pyramidal, with two O and two N atoms of L3 in the basal plane and one O atom from an acetate group in the apical position. The acetate bridges linking the central and terminal Cu2+ ions are mutually trans. The Cu···Cu separation is 3.009(3) Å. In 4 , the coordination configuration of the central and the terminal zinc atoms are similar to that of the 3 , with Zn···Zn separation of 3.153(4) Å. The three Schiff bases and the corresponding three copper complexes exhibit good antibacterial properties, while the zinc complex 4 has nearly no.  相似文献   

13.
Three new dinuclear Zn(II) complexes [Zn(L)(μ1,1-N3)Zn(L)(N3)] · 1.5H2O (1), [Zn(L)(μ1,1-NCO)Zn(L)(NCO)] · 1.5H2O (2) and [Zn(L)(μ1,1-NCS)Zn(L)(NCS)(OH2)] (3) have been synthesized from a potentially tetradentate N2O2-donor Schiff base ligand LH, [LH = (OCH3)(OH)C6H3CHN(CH2)2N(CH3)2], which is the condensation product of o-vanillin and 2-dimethylaminoethylamine. All the three complexes 1, 2 and 3 have been characterized by elemental analysis, IR and 1H NMR spectroscopy, TGA and fluorescence studies. Finally, their structures have been established by the single crystal X-ray diffraction method. Structural studies reveal that in complexes 1, 2 and 3 the two Zn(II) centers are held together by a μ2-phenolato oxygen atom and also by an end-on pseudohalide nitrogen (azide for 1; cyanate for 2; thiocyanate for 3) atom. Among the two deprotonated Schiff base ligands present in each complex, one acts as a tetradentate ligand (N2O2 donor set) while the other acts as a tridentate ligand (N2O donor set), having a non-coordinated methoxy group. All the synthesized complexes display intraligand 1(π–π) fluorescence and can potentially serve as photoactive materials.  相似文献   

14.
Four Schiff base complexes, [Zn2L2(NCS)2] ( 1 ), [Cd2L2(NCS)2]n ( 2 ), [Zn4L2(N3)2Cl4(OH2)(CH3OH)] ( 3 ), and [Cu4L2(N3)2Cl4(OH2)(CH3OH)] ( 4 ) (where L = 2‐[(2‐dimethylaminoethylimino)methyl]phenol), were synthesized and characterized by elemental analyses, infrared spectroscopy, and single crystal X‐ray determinations. Both 1 and 2 are structurally similar polynuclear complexes. In 1 , each Zn atom has a slightly distorted square‐pyramidal coordination configuration. In the basal plane, the Zn atom is coordinated by one O and two N atoms of one L, and by one O atom of another L. The apical position is occupied by one terminal N atom of a coordinated thiocyanate anion. The Zn···Zn separation is 3.179(3) Å. While in 2 , the Cd1 atom is six‐coordinated in an octahedral coordination. In the equatorial plane, the Cd1 atom is coordinated by one O and two N atoms of one L, and by one O atom of another L. The axial positions are occupied by the terminal N and S atoms from two bridging thiocyanate anions. The coordination of Cd2 atom in 2 is similar to those of the zinc atoms in 1 . The Cd···Cd separation is 3.425(2) Å. Both 3 and 4 are novel tetra‐nuclear complexes. Each metal atom in the complexes has a slightly distorted square‐pyramidal coordination. The arrangements of the terminal metal atoms are similar, involving one O and two N atoms of one L ligand and one bridging Cl atom defining the basal plane, and one O atom of a coordinated water molecule or MeOH molecule occupying the apical position. The coordinations of the central metal atoms are also similar. The basal plane of each metal atom involves one O atom of one L ligand, one terminal Cl atom, and two terminal N atoms from two bridging azide groups. The apical position is occupied by a bridging Cl atom which also acts as a basal donor atom of the terminal metal atom. The Schiff base ligand and the four complexes showed high selectivity and antibacterial activities against most of the bacteria.  相似文献   

15.
In the crystal structure of the title complex, [Zn(N3)2(C6H8N6)]n or [Zn(N3)2(bte)]n, where bte is μ‐1,2‐bis(1,2,4‐triazol‐1‐yl)­ethane, each Zn atom is pentacoordinated in a distorted trigonal‐bipyramidal coordination environment involving two N atoms from two bte ligands and three N atoms from three azide ligands. The Zn atoms are bridged by μ‐1,1‐azide groups and bte ligands around a centre of inversion, forming an infinite one‐dimensional chain containing both four‐membered Zn(μ‐1,1‐N3)2Zn and 18‐membered Zn(gauche‐bte)2Zn rings.  相似文献   

16.
Two novel azide cadmium(II) compounds [Cd4(dafone)4Cl21,1-N3)41,1,1-N3)2] (1) and [Cd4(dafone)4(N3)21,1-N3)41,1,1-N3)2] (2) were synthesized and characterized by spectroscopic and crystallographic methods. They are first cadmium(II) complexes adopting double open cubane-like structure. The fluorescence properties of the complexes 1 and 2 were examined both in solid state and solution, and compared with the free ligand. Additionally, the electronic spectra of 4,5-diazafluoren-9-one and 1 were investigated at the TDDFT level.  相似文献   

17.
The azide anion is a short bridging ligand that has been used extensively to construct magnetic coordination polymers, and fundamental magneto‐structural correlations have been substantiated by theoretical calculations. The copper(II) coordination polymer poly[bis(μ‐azido‐κ2N1:N1)(μ4‐homophthalato‐κ4O:O′:O′′:O′′′)bis(pyridine‐κN)dicopper(II)], [Cu2(C9H6O4)(N3)2(C5H5N)2]n, was synthesized from homophthalic acid (2‐carboxyphenylacetic acid), pyridine and azide (N3) by a hydrothermal reaction. Single‐crystal structure analysis indicated that it features a one‐dimensional chain structure which is comprised of (μ1,1‐N3)(μ‐synsyn‐COO)2‐ and (μ1,1‐N3)2‐bridged tetranuclear CuII units. Magnetic measurements revealed that the compound exhibits dominant antiferromagnetic behaviour.  相似文献   

18.
One-pot reactions of cadmium(II) perchlorate/nitrate, Schiff bases (pbap/pfap) and pseudohalides (sodium azide/ammonium thiocyanate) in a 2:1:4 molar ratio in MeOH–MeCN solvent mixtures at room temperature result in a dinuclear compound [Cd2(pbap)(OH2)2(N3)4] (1) [pbap = N-(1-pyridin-2-ylbenzylidene)-N-[2-(4-{2-[(1-pyridin-2-ylbenzylidene)amino]ethyl}piperazin-1-yl)ethyl]amine] and a polymeric compound [Cd2(pfap)(μ1,3-NCS)(μ1,3-SCN)(NCS)2]n (2) [pfap = N-(1-pyridin-2-ylformylidene)-N-[2-(4-{2-[(1-pyridin-2ylformylidene)amino]ethyl}piperazin-1-yl)ethyl]-amine]. X-ray crystal structural analyses reveal a bis(tridentate) congregation behaviour of the hexadentate blocker (pbap/pfap) encapsulating two metal centers. Each cadmium(II) center in 1 and 2 is in a distorted octahedral geometry with CdN5O and CdN5S chromophores, respectively. In 1, the dinuclear units participate in intermolecular O–H?N hydrogen bonding between bound water O atoms and terminal azide N atoms, in combination with C–H?π interactions, resulting in a 3D supramolecular network with an intramolecular Cd?Cd distance of 6.473(2) Å. In the crystal lattice, the covalent 1D chain of 2 is further engaged in face-to-face π?π interactions from two terminal pyridine rings, which stabilizes the chain with an intradimer Cd?Cd separation of 6.640(5) Å. Both the complexes display intraligand 1(π–π) fluorescence and intraligand 3(π–π) phosphorescence in glassy solutions.  相似文献   

19.
A new double asymmetric μ1,1-azido bridged binuclear copper(II) complex, [Cu21,1-N3)2(Him2-py)2(N3)2] (Him2-py?=?2-(2′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-hydroxy), has been synthesized and characterized structurally and magnetically. The crystal structure shows this complex is binuclear with copper(II) in a distorted square-pyramidal geometry, bridged by double asymmetric end-on azide ligands. The variable temperature magnetic susceptibility analyses reveal weak antiferromagnetic interaction mediated by the bridge.  相似文献   

20.
In the title cadmium metal–organic framework complex, [Cd(C8H3NO6)(C24H16N2)]n or [Cd(NIPH)(dpphen)] (NIPH is nitroisophthalate and dpphen is 4,7‐diphenyl‐1,10‐phenanthroline), the unique CdII cation in a general position is coordinated by four carboxy O atoms from three symmetry‐related NIPH anions and two N atoms from a dpphen ligand. The CdII cations are bridged by pairs of NIPH anions to generate a dinuclear molecular building block, [Cd2N4(CO2R)4], with a Cd...Cd separation of 4.0936 (10) Å. Each such building block is connected to four adjacent dinuclear building blocks by NIPH anions, resulting in a two‐dimensional layer framework in the bc plane. The dpphen ligands occupy the space between these layers and are linked by π–π interactions, with a separation of 3.4541 (6) Å between the central aromatic rings of inversion‐related dpphen ligands. The thermogravimetric and photoluminescent properties of the complex have also been investigated.  相似文献   

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