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1.
Two dinuclear succinato‐bridged nickel(II) complexes [Ni(RR‐L)]2(μ‐SA)(ClO4)2 ( 1 ) and [Ni(SS‐L)]2(μ‐SA)(ClO4)2 ( 2 ) (L = 5, 5, 7, 12, 12, 14‐hexamethyl‐1, 4, 8, 11‐tetraazacyclotetradecane, SA = succinic acid) were synthesized and characterized by EA, Circular dichroism (CD), as well as IR and UV/Vis spectroscopy. Single crystal X‐ray diffraction analyses revealed that the NiII atoms display a distorted octahedral coordination arrangement, and the succinato ligand bridges two central NiII atoms in a bis bidentate fashion to form dimers in 1 and 2 . The monomers of {[Ni(RR‐L)]2(μ‐SA)}2+ and {[Ni(SS‐L)]2(μ‐SA)}2+ are connected by O–H ··· O and N–H ··· O hydrogen bonds into a 1D right‐handed and left‐handed helical chain along the b axis, respectively. The homochiral natures of 1 and 2 are confirmed by the results of CD spectroscopy.  相似文献   

2.
Two CoII complexes, namely {[CoL(MeOH)(μ-OAc)]2Co}·2MeCN·2MeOH (1) and {[CoL(EtOH)(μ-OAc)]2Co}·3EtOH (2) (H2L=3,3′-dimethoxy-2,2′-[(1,3-propylene)dioxybis(nitrilomethylidyne)]diphenol), have been synthesized and characterized by X-ray crystallography. Both complexes contain octahedral coordination geometries, comprising three CoII atoms, two deprotonated bisoxime L2− units in which four μ-phenoxo oxygen atoms form two [CoL(X)] (X = MeOH or EtOH) units, two acetate ligands coordinated to three CoII centers through Co–O–C–O–Co bridges, and coordinated and non-coordinated solvent. Both complexes exhibit 2D supramolecular networks through different intermolecular hydrogen-bonding interactions.  相似文献   

3.
Four new solvent‐induced Ni(II) complexes with chemical formulae [{NiL(μ2‐OAc)(MeOH)}2Ni]·2MeOH ( 1 ), [{NiL(μ2‐OAc)}2(n‐PrOH)(H2O)Ni]·n‐PrOH ( 2 ), [{NiL(μ2‐OAc)(DMF)}2Ni] ( 3 ) and [{NiL(μ2‐OAc)(DMSO)}2Ni]·2DMSO ( 4 ), (H2L = 4‐Nitro‐4′‐chloro‐2,2′‐[(1,3‐propylene)dioxybis(nitrilomethylidyne)]diphenol) have been synthesized and characterized by elemental analyses, FT‐IR, UV–Vis spectra and X‐ray crystallography. X‐ray crystal structure determinations revealed that each of the Ni(II) complexes 1–4 consists of three Ni(II) atoms, two completely deprotonated (L)2? units, two μ2‐acetate ions and two coordinated solvent molecules (solvents are methanol, n‐propanol, water, N,N‐dimethylformamide and dimethyl sulphoxide, respectively). Although the four complexes 1–4 were synthesized in different solvents, it is worthwhile that the Ni(II) atoms in the four complexes 1–4 adopt hexa–coordinated with slightly distorted octahedral coordination geometries, and the ratios of the ligand H2L to Ni(II) atoms are all 2: 3. The complexes 1–4 possess self‐assembled infinite 1D, 3D, 1D and 2D supramolecular structures via the intermolecular hydrogen bonds, respectively. In addition, fluorescence behaviors were investigated in the complexes 1–4 .  相似文献   

4.
Two trinuclear CoII and ZnII complexes, [(CoL)2(OAc)2Co] and [(ZnL)2(OAc)2Zn], with an asymmetric Salen‐type bisoxime ligand [H2L = 4‐(N,N‐diethylamine)‐2,2′‐[ethylenediyldioxybis(nitrilomethylidyne)]diphenol] were synthesized and characterized by elemental analyses, IR, UV/Vis, and fluorescent spectroscopy. The crystal structures of the CoII and ZnII complexes were determined by single‐crystal X‐ray diffraction methods. The CoII atom is pentacoodinated by N2O2 donor atoms from the (L)2– unit and one oxygen atom from the coordinated acetate ion, resulting in a trigonal bipyramid arrangement. With the help of intermolecular hydrogen bonding C–H ··· O and C–H ··· π interactions, a self‐assembled continual zigzag chain‐like supramolecular structure is formed. The ZnII atom is pentacoodinated by N2O2 donor atoms from the (L)2– unit and one oxygen atom from the coordinated acetate ion, resulting in an almost regular trigonal bipyramid arrangement. A self‐assembled continual 1D supramolecular chain‐like structure is formed by intermolecular hydrogen bonding C–H ··· O and C–H ··· π interactions. Additionally, the photophysical properties of the CoII and ZnII complexes were discussed.  相似文献   

5.
A novel trinuclear NiII cluster, {[Ni(H2L)(EtOH)]2(OAc)2Ni} · 2EtOH [H4L:5,5′-Dihydroxy-2,2′-[ethylenedioxybis(nitrilomethylidyne)]diphenol], has been synthesized and structurally characterized. The X-ray crystal structure of the cluster reveals that two acetates coordinate to three nickel ions through Ni–O–C–O–Ni bridges and four μ-phenoxo oxygen atoms from two [Ni(H2L)] units also coordinate to nickel ions. Around three nickel atoms are all octahedral geometries.  相似文献   

6.
Two new complexes, {[Co(INAIP) · H2O] · 2H2O}n ( 1 ), and {[Cu(INAIP)] · H2O}n ( 2 ) [H2INAIP = 5‐(isonicotinamido)isophthalic acid] were synthesized under hydrothermal conditions, and characterized by single‐crystal X‐ray structure determination, thermogravimetric analysis, X‐ray powder diffraction, and magnetic studies. In complex 1 both CoII atoms and INAIP2– ligands act as four‐connected node, whereas in 2 both CuII atoms and INAIP2– ligands act as three‐connected node.  相似文献   

7.
Reaction of the flexible phenolic carboxylate ligand 2‐(3,5‐dicarboxylbenzyloxy)benzoic acid (H3L) with nickel salts in the presence of 1,2‐bis(pyridin‐4‐yl)ethylene (bpe) leads to the generation of a mixture of the two complexes under solvolthermal conditions, namely poly[[aqua[μ‐1,2‐bis(pyridin‐4‐yl)ethylene‐κ2N:N′]{μ‐5‐[(2‐carboxyphenoxy)methyl]benzene‐1,3‐dicarboxylato‐κ3O1,O1′:O3}nickel(II)] dimethylformamide hemisolvate monohydrate], {[Ni(C16H10O7)(C12H10N2)(H2O)]·0.5C3H7NO·H2O}n or {[Ni(HL)(bpe)(H2O)]·0.5DMF·H2O}n, 1 , and poly[[diaquatris[μ‐1,2‐bis(pyridin‐4‐yl)ethylene‐κ2N:N′]bis{μ‐5‐[(2‐carboxyphenoxy)methyl]benzene‐1,3‐dicarboxylato‐κ2O1:O5}nickel(II)] dimethylformamide disolvate hexahydrate], {[Ni2(C16H10O7)2(C12H10N2)3(H2O)2]·2C3H7NO·6H2O}n or {[Ni2(HL)2(bpe)3(H2O)2]·2DMF·6H2O}n, 2 . In complex 1 , the NiII centres are connected by the carboxylate and bpe ligands to form two‐dimensional (2D) 4‐connected (4,4) layers, which are extended into a 2D+2D→3D (3D is three‐dimensional) supramolecular framework. In complex 2 , bpe ligands connect to NiII centres to form 2D layers with Ni6(bpe)6 metallmacrocycles. Interestingly, 2D+2D→3D inclined polycatenation was observed between these layers. The final 5‐connected 3D self‐penetrating structure was generated through further connection of Ni–carboxylate chains with these inclined motifs. Both complexes were fully characterized by single‐crystal analysis, powder X‐ray diffraction analysis, FT–IR spectra, elemental analyses, thermal analysis and UV–Vis spectra. Notably, an interesting metal/ligand‐induced crystal‐to‐crystal transformation was observed between the two complexes.  相似文献   

8.
Two new tetranuclear NiII complexes, [Ni4(L1)2(N3)4(MeOH)2]·CH3COCH3 (1) and [Ni4(L2)2(N3)4(MeOH)2]·4CH3COCH3 (2) , were synthesized using NiCl2·6H2O, NaN3, and asymmetric salamo‐based ligands H2L1 and H2L2, respectively. The structural characterization was made by elemental analyses, infrared (IR) and ultraviolet‐visible (UV‐vis) spectra, and X‐ray diffraction analyses. The results of X‐ray diffraction analyses show that the NiII atoms in complexes 1 and 2 are distorted octahedral geometries. Interestingly, the degree of distortion of the ligands in complexes 1 and 2 is different, which indicates that the interaction of NiII ions on different ligands is different. Meanwhile, the investigation of molecular packing by employing the Hirshfeld surface analysis exhibits that the percentages of C–H/H–C, O–H/H–O, and H–H/H–H contacts of the complex 1 (or 2 ) are calculated to be 17.7%, 7.9%, and 53.7% (or 18.8%, 13.8%, and 52.5%), respectively, where the H–H/H–H contacts have the characteristics of strong contacts whereas the O–H/H–O hydrogen bonds are considerably weak, and the studies on fluorescence properties further confirm the NiII atoms have different binding abilities to the different ligands.  相似文献   

9.
The CoII cation in poly[[aqua(μ‐benzene‐1,2‐dicarboxylato‐κ3O1,O2:O1)(μ‐4,4′‐bipyridine‐κ2N:N′)cobalt(II)] trihydrate], {[Co(C8H4O4)(C10H8N2)(H2O)]·3H2O}n, is octahedrally coordinated by two N atoms of two 4,4′‐bipyridine ligands, three O atoms from phthalate anions and a fourth O atom from a coordinated water molecule. The packing consists of planes of coordination polymers linked by hydrogen bonds mediated by three solvent water molecules; the linkage is achieved by the water molecules forming intricate oligomeric clusters which also involve the O atoms of the phthalate ligands.  相似文献   

10.
Coordination polymers of CuII and NiII with 3-pyridin-3-yl-benzoic acid (3,3-Hpybz), {[Cu(3,3-pybz)2(CH3OH)]·(DMF)} n (1) and {[Ni(3,3-pybz)2(H2O)]?·?(H2O)} n (2), were synthesized and characterized by single-crystal X-ray diffraction, thermogravimetric analyses, elemental analysis, and IR spectroscopy. In 1, CuII ions are linked by paired 3,3-pybz ligands to generate an in?nite 1-D double-strand chain. However, NiII ions in 2 are linked by the 3,3-pybz to form a 2-D corrugated network with a simple (4,4) topology; these 2-D layers are further enlarged to form the final 3-D supramolecular edifice via strong aromatic π–π stacking interactions and O–H?···?O hydrogen bonds. Magnetic properties of 1 and 2 have also been investigated.  相似文献   

11.
Schiff bases are considered `versatile ligands' in coordination chemistry. The design of polynuclear complexes has become of interest due to their facile preparations and varied synthetic, structural and magnetic properties. The reaction of the `ligand complex' [CuL] {H2L is 2,2′‐[propane‐1,3‐diylbis(nitrilomethanylylidene)]diphenol} with Ni(OAc)2·4H2O (OAc is acetate) in the presence of dicyanamide (dca) leads to the formation of bis(dicyanamido‐1κN1)bis(dimethyl sulfoxide)‐2κO,3κO‐bis{μ‐2,2′‐[propane‐1,3‐diylbis(nitrilomethanylylidene)]diphenolato}‐1:2κ6O,O′:O,N,N′,O′;1:3κ6O,O′:O,N,N′,O′‐dicopper(II)nickel(II), [Cu2Ni(C17H16N2O2)2(C2N3)2(C2H6OS)2]. The complex shows strong absorption bands in the frequency region 2155–2269 cm−1, which clearly proves the presence of terminal bonding dca groups. A single‐crystal X‐ray study revealed that two [CuL] units coordinate to an NiII atom through the phenolate O atoms, with double phenolate bridges between CuII and NiII atoms. Two terminal dca groups complete the distorted octahedral geometry around the central NiII atom. According to differential thermal analysis–thermogravimetric analysis (DTA–TGA), the title complex is stable up to 423 K and thermal decomposition starts with the release of two coordinated dimethyl sulfoxide molecules. Free H2L exhibits photoluminescence properties originating from intraligand (π–π*) transitions and fluorescence quenching is observed on complexation of H2L with CuII.  相似文献   

12.
A chelating bisoxime ligand, 2,2′-[(1,3-propylene)dioxybis(nitrilomethylidyne)]dinaphthol (H2L), and its corresponding Ni(II) cluster {[NiL(H2O)]2(OAc)2Ni} · 0.5MeOH · 0.5CH3CN · H2O (1) have been synthesized and characterized by elemental analyses, TG-DTA, IR, 1H NMR and X-ray diffraction methods. The Ni(II) cluster is monoclinic, space group P2(1)/c with cell dimensions a = 9.400(2), b = 24.530(4), c = 25.350(3) Å and β = 92.823(3)°. In the Ni(II) cluster, there are two ligand moieties (which provide N2O2 donors), two acetate ions and two water molecules, which result in three slightly distorted octahedral geometries around the Ni(II) ions.  相似文献   

13.
Three coordination compounds [Mn3(dmb)6(H2O)4(4, 4′‐bpy)3(EtOH)]n ( 1 ) and [M(dmb)2(pyz)2 (H2O)2] [MII = Co ( 2 ), Mn ( 3 )] (Hdmb = 2, 6‐dimethoxybenzoic acid, 4, 4′‐bpy = 4, 4′‐bipyridine, pyz = pyrazine) were synthesized and characterized by single‐crystal X‐ray diffraction analysis. Compound 1 consists of infinite 1D polymeric chains, in which the metal entities are bridged by 4, 4′‐bpy ligands. There are four crystallographically independent MnII atoms in the linear chain with different coordination modes, which is only scarcely reported for linear polymers. The isostructural crystals of 2 and 3 are composed of neutral mononuclear complexes. In crystal the complexes are combined into chains by intermolecular O–H ··· N hydrogen bonds and π–π interactions between antiparallel pyrazine molecules.  相似文献   

14.
Two tetranuclear clusters of formula [M4L4(HOMe)4] {H2L = (E)‐1‐[(2‐(hydroxymethyl)phenylimino)methyl]naphthalen‐2‐ol} [M = Co ( 1 ), Ni ( 2 )] were hydrothermally synthesized by reaction of M(OAc)2 · 4H2O with H2L and NaOH in MeOH. X‐ray crystal structure analysis revealed that complexes 1 and 2 are isostructural. In the core of the structures, four MII ions and four oxygen atoms occupied alternate vertices of [M4O4] cubane. The magnetic property measurements of 1 and 2 revealed that overall ferromagnetic MII ··· MII exchange interactions exist in both complexes.  相似文献   

15.
The reduction of 2‐cyanopyridine by sodium in dry methanol in the presence of thiosemicarbazide produces 2‐pyridineformamide thiosemicarbazone, HAm4DH. The reactions of the potentially tridentate ligand HAm4DH with salts of Zn, Cd, and Hg gave a variety of metal‐ligand complexes. The complexes were characterized by mass spectrometry as well as IR and multinuclear NMR (1H, 13C, 13C CP/MAS, 113Cd, 199Hg) spectroscopy. The crystal structures of [Zn(Am4DH)(OAc)]2·H2O, [Hg(HAm4DH)2Br2]·C2H5OH and [Hg(μ‐S‐Am4DH)Br] were obtained. Coordination of anionic Am4DH? occurs through the pyridyl nitrogen, imine nitrogen and thiolato sulfur atoms, while the neutral ligands in [Hg(HAm4DH)2Br2] coordinate as monodentate ligands through their thione sulfur atoms. One of the acetate ligands in [Zn(Am4DH)(OAc)]2·H2O is bridging monodentate and the other bridging bidentate. [Hg(μ‐S‐Am4DH)Br] features five‐coordinate mercury centers with bridging thiolato sulfur atoms. The intermolecular arrangement is dictated by hydrogen bonding from the amino groups and by π‐π stacking of the pyridine rings.  相似文献   

16.
Three novel complexes, namely [Zn(CuL)(pzdc)]2 · 5H2O ( 1 ), [Zn(NiL)(pzdc)]2 · 5H2O ( 2 ), and [Gd2(pzdc)2(NiL)6](ClO4)2 · 6H2O ( 3 ) (CuL and NiL, H2L = 2, 3‐dioxo‐5, 6, 14, 15‐dibenzo‐1, 4, 8, 12‐tetraazacyclo‐pentadeca‐7, 13‐dien and H2pzdc = pyrazine‐2, 3‐dicarboxylic acid) were synthesized and structurally determined. Complexes 1 and 2 are tetranuclear [ZnII2MII2] (M = Ni ( 1 ), Cu ( 2 ), respectively) molecules including both oxamide and pzdc2– bridges. The structure of compound 3 consists of pyrazine‐2, 3‐dicarboxylate and oxamido‐bridged, and is arranged in different butterfly‐like octanuclear molecules. The magnetic susceptibility data of 3 were analyzed.  相似文献   

17.
The new asymmetrical organic ligand 2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole ( L , C17H13N5O), containing pyridine and imidazole terminal groups, as well as potential oxdiazole coordination sites, was designed and synthesized. The coordination chemistry of L with soft AgI, CuI and CdII metal ions was investigated and three new coordination polymers (CPs), namely, catena‐poly[[silver(I)‐μ‐2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole] hexafluoridophosphate], {[Ag( L )]PF6}n, catena‐poly[[copper(I)‐di‐μ‐iodido‐copper(I)‐bis(μ‐2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole)] 1,4‐dioxane monosolvate], {[Cu2I2( L )2]·C4H8O2}n, and catena‐poly[[[dinitratocopper(II)]‐bis(μ‐2‐{4‐[(1H‐imidazol‐1‐yl)methyl]phenyl}‐5‐(pyridin‐4‐yl)‐1,3,4‐oxadiazole)]–methanol–water (1/1/0.65)], {[Cd( L )2(NO3)2]·2CH4O·0.65H2O}n, were obtained. The experimental results show that ligand L coordinates easily with linear AgI, tetrahedral CuI and octahedral CdII metal atoms to form one‐dimensional polymeric structures. The intermediate oxadiazole ring does not participate in the coordination interactions with the metal ions. In all three CPs, weak π–π interactions between the nearly coplanar pyridine, oxadiazole and benzene rings play an important role in the packing of the polymeric chains.  相似文献   

18.
Tri-nuclear cobalt and nickel complexes ([(CoL)2(OAc)2Co]?·?THF (I) and [(NiL)2(OAc)2(THF)2Ni]?·?THF (II)) have been synthesized by reaction of a new Salen-type bisoxime chelating ligand of 2,2′-[ethylenedioxybis(nitrilomethylidyne)]dinaphthol(H2L) with cobalt(II) acetate tetrahydrate or nickel(II) acetate tetrahydrate, respectively. Complexes I and II were characterized by elemental analyses, IR, TG-DTA and 1H-NMR etc. The X-ray crystal structures of I and II reveal that two acetate ions coordinate to three cobalt or nickel ions through M–O–C–O–M (M?=?Co or Ni) bridges and four μ-naphthoxo oxygen atoms from two [ML] units also coordinate to cobalt(II) or nickel(II). Complex I has two distorted square-pyramidal coordination spheres and an octahedral geometry around Co1. In complex II all three nickel ions are six-coordinate.  相似文献   

19.
Magnesium acetate solvates, Mg(OAc)2 · nL, and their hydrates were prepared by crystallization of Mg(OAc)2 · 4H2O or Mg(OAc)2 from different solvents (L = MeOH, EtOH, HOAc). Anhydrous Mg(OAc)2 was obtained by thermal dehydration of the tetrahydrate at 150 °C. X‐ray single crystal diffraction mostly with the use of synchrotron radiation allowed the structure determination of Mg(OAc)2(H2O)3(EtOH) ( I ), Mg(OAc)2(HOAc)2(H2O)2 ( II ), Mg3(OAc)6(MeOH)6 ( III ), Mg3(OAc)6(HOAc)2(H2O)2 · 2HOAc ( IV ), Mg(OAc)2(HOAc) · 1.8(HOAc) ( V ), Mg(OAc)2 · H2O ( VI ), [Mg3(OAc)6(EtOH)2] · 2EtOH ( VII ), and Mg(OAc)2 ( VIII ). Structural data were discussed in terms of the number of neutral O‐donor ligands per magnesium atom, coordination environment of magnesium atoms, structural functions of acetate groups, and hydrogen bonding systems.  相似文献   

20.
Two new one‐dimensional (1D) coordination polymers (CPs), namely catena‐poly[[[aquacadmium(II)]‐bis(μ‐4b,5,7,7a‐tetrahydro‐4b,7a‐epiminomethanoimino‐6H‐imidazo[4,5‐f][1,10]phenanthroline‐6,13‐dione)] bis(perchlorate) dihydrate], {[Cd(C14H10N6O2)2(H2O)](ClO4)2·2H2O}n or {[Cd(BPG)2(H2O)](ClO4)2·2H2O}n, 1 , and catena‐poly[[lead(II)‐bis(μ‐4b,5,7,7a‐tetrahydro‐4b,7a‐epiminomethanoimino‐6H‐imidazo[4,5‐f][1,10]phenanthroline‐6,13‐dione)] bis(perchlorate) dihydrate], {[Pb(C14H10N6O2)2](ClO4)2·2H2O}n or {[Pb(BPG)2](ClO4)2·2H2O}n, 2 , have been synthesized using bipyridine–glycoluril (BPG; systematic name: 4b,5,7,7a‐tetrahydro‐4b,7a‐epiminomethanoimino‐6H‐imidazo[4,5‐f][1,10]phenanthroline‐6,13‐dione), a urea‐fused tecton, in a mixed‐solvent system. The CdII ion in 1 is heptacoordinated and the PbII ion in 2 is hexacoordinated, with the CdII ion adopting a pentagonal bipyramidal geometry and the PbII ion adopting a distorted octahedral geometry. Both CPs form infinite linear chain structures which are hydrogen bonded to each other leading to the formation of three‐dimensional supramolecular network structures. Topological analysis of CPs 1 and 2 reveals that the structures exhibit 1D chain‐like arrangements in an AB–AB sequence and shows platonic uniform 2‐connected uninodal topologies. Furthermore, a comparative analysis of a series of structures based on the BPG ligand indicates that the size of the metal ion and the types of counter‐ions used have a great influence on the resulting frameworks and properties.  相似文献   

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