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1.
Vladimir Ya. Lee 《Journal of organometallic chemistry》2007,692(13):2800-2810
The heavy analogues of the anionic 6π-electron systems, lithium 1,2-disila-3-germacyclopentadienide 2− · [Li+(thf)], 1,2-disila-3,4-digerma- and 1,2,3,4-tetrasilacyclobutadiene dianions 72− · 2[K+(thf)2] and 82− · 2[K+(thf)2], were synthesized by the reduction of the neutral precursors 1, 3 and 4, respectively. 2− · [Li+(thf)], the heavy analogue of the cyclopentadienide ion, is an aromatic compound, whereas 72− · 2[K+(thf)2] and 82− · 2[K+(thf)2], the heavy analogues of the cyclobutadiene dianion, are both non-aromatic. 相似文献
2.
Two polyoxometalate (POM) supramolecular assemblies based on W18 clusters and the rigid organic trans-1,2-di-(4-pyridyl)-ethylen (bpe) have been synthesized and fully characterized, namely (H2bpe)3.5H2[SbW18O60]·5H2O (1), and (H2bpe)5[Ni4(AsW9O34)2(H2O)2]·3H2O (2). Compounds 1-2 are formed from organic bpe cations and different polytungstate anions: pseudo-Dawson-type [SbW18O60]9− in 1 and sandwich-type [Ni4(H2O)2(AsW9O34)2]10− in 2. Both of compounds 1-2 crystallize in a low-symmetrical space group of P-1 and consist of a complicated supramolecular network based on non-covalent intermolecular weak interactions, including hydrogen bonding and π···π stacking. The multipoint hydrogen bonding interactions constitute the structural feature in two supramolecular frameworks. The UV-vis, fluorescence and electrochemistry properties are also studied. 相似文献
3.
Shin-ichi Naya 《Tetrahedron》2004,60(41):9139-9148
Ring transformation of 7,9-dimethylcyclohepta[b]pyrimido[5,4-d]furan- 8(7H),10(9H)-dionylium tetrafluoroborate 4+·BF4− to 7,9-dimethylcyclohepta[b]pyrimido[5,4-d]pyrrrole-8(7H),10(9H)-dionylium tetrafluoroborate 6a-d+·BF4− consists of the reaction of 4+·BF4− with amines and subsequent exchange of the counter-ion using aq. HBF4. Reactions of 4+·BF4− with aniline and 4-substituted anilines afforded the corresponding pyrrole derivatives 6a-c+·BF4− directly in good yields. On the other hand, reaction of 4+·BF4− with benzylamine gave the troponeimine intermediate 9, which was not converted to 6d+·BF4− and reverted to 4+·BF4− by adding HBF4; however, it was converted to 6d+·BF4− upon treatment with (COCl)2 or SOCl2, followed by exchange of the counter-ion. In a search for the characteristics of 9, inspection and comparison of the X-ray crystal analyses, NMR and UV-vis spectra, and CV measurement of 9 and N,N-disubstituted troponeimine derivatives 12 were carried out to suggest the remarkable structure of 12 having ionic C-O bonding between the imine-carbon atom and the oxygen atom of the barbituric acid moiety in the solid state. Thus, characteristics of 9 were ascribed to the sterically hindered and favorable conformation of N-protonated troponeimine intermediates. Furthermore, novel photo-induced oxidation reactions of a series of 4+·BF4−, 5+·BF4−, and 6a,e+·BF4− towards some amines under aerobic conditions were carried out to give the corresponding imines in 455-8362% yields [based on compounds 4+, 5+, and 6a,e+], suggesting the oxidation reaction occurs in an autorecycling process. Mechanistic aspects of the amine-oxidation reaction are also postulated. 相似文献
4.
Shin-ichi Naya 《Tetrahedron》2005,61(21):4919-4930
Novel photo-induced oxidative cyclization was accomplished to synthesize areno[b]pyrimido[5,4-e]pyran-2,4(1,3H)-dionylium ions 13a-c+·ClO4−. Furthermore, 13a-c+·BF4− and their phenyl-substituted derivatives 19a,b+·BF4− were alternatively synthesized by the reaction of salicylaldehyde and its naphthyl derivatives with barbituric acids and subsequent treatment with aq. HBF4. Structural characteristics of 13a-c+ and 19a,b+ were clarified on inspection of the UV-vis and NMR spectral data as well as X-ray crystal analyses. The electrochemical properties were studied by the CV measurement. In a search for reactivity, reactions of 13a-c+·BF4− with some nucleophiles, hydride, benzylamine, and H2O, were also carried out. The photo-induced autorecycling oxidation reactions of 13a-c+·BF4− toward some amines under aerobic conditions were carried out to give the corresponding imines (isolated by converting to the corresponding 2,4-dinitrophenylhydrazones) in 643-3600% yield (recycling number of 13a-c+·BF4−: 6.4-36.0). 相似文献
5.
A new ion-pair receptor bis(3-bromoindol-2-ylmethyl)(2-pyridylmethyl)amine (1) was synthesized and studied for its anion and cation binding behavior using ESI-MS and 1H NMR spectroscopy. Among halides, 1 exhibits the strongest binding with Cl− to form a 1:1 adduct (Ka = 1042 ± 21 in CD3CN). Among alkali metal ions, Li+ and Na+ showed the strongest binding in the formation of a 1·M+ complex. The simultaneous binding of Cl− and Li+ to 1 was confirmed by 1H NMR titration of a 1:1 mixture of 1 and Cl− with LiPF6 in 83:17 v/v mixture of CDCl3 and DMSO-d6. DFT-optimized structures of 1·Cl−, 1·Li+, and 1·Li+·Cl− are consistent with the chemical shift changes observed in 1H NMR studies. 相似文献
6.
Four tetrahydrofuran-2,3,4,5-tetracarboxylato bridged copper(II) coordination polymers with alkali metals, Na2[Cu(H2O)(THFTC)]·5H2O 1, K2[Cu3(H2O)2(THFTC)2]·9H2O 2, Rb2[Cu3(H2O)2(THFTC)2]·6H2O 3 and Cs2[Cu3(H2O)2(THFTC)2]·6H2O 4 (H4THFTC = tetrahydrofuran-2,3,4,5-tetracarboxylic acid) were prepared from reactions of Cu(NO3)2·3H2O, tetrahydrofuran-2,3,4,5-tetracarboxylic acid and alkali hydroxide or carbonate at pH 5.0–6.0 under ambient conditions. Compound 1 features 2D (33·43·54) topological layers generated from six-coordinated Cu2+ cations interlinked by (THFTC)4− anions, and the resulting layers are ecliptically stacked along [1 0 0] direction to form lozenge-shaped and octagonal channels filled with Na+ ions and lattice H2O molecules. In 2–4, both penta- and hexa-coordinated copper(II) ions are bridged by tetracarboxylate anions to form negatively charged 2D layers formulated as 2∞[Cu(H2O)2L3/2]2− with the corresponding alkali metal cations (K+, Rb+ or Cs+ ions) and hydrogen bonded lattice H2O molecules sandwiched between them. Additionally, the results about i.r. spectroscopic, thermal characterizations and magnetic properties are presented. 相似文献
7.
Calix[4]arenes containing urea and crown/urea moieties: effects of the crown ether unit and Na towards anion binding ability 总被引:1,自引:0,他引:1
Calix[4]arenes containing urea and crown/urea moieties, 7 and 10, respectively have been synthesized. 1H NMR titrations of 7 and 10 with anions in DMSO-d6 showed that 7 and 10 formed complexes with Cl−, Br−, NO3− and H2PO4− to a different extent. The association constants of 7 and 10 towards anions were calculated and found to vary as H2PO4−>Cl−>Br−>NO3−. However, compared to 7 the presence of the crown unit in 10 resulted in a slightly higher affinity to Cl− and Br−, but a lower affinity to H2PO4−. Upon addition of Na+, the binding ability of 10 towards H2PO4− is increased due to ion-pair enhancement. 相似文献
8.
Bo Gao Lin-Hua Xie Miao Yu Chun-Dan Zhang Chun-Yan Sun Hai-Yan Cheng 《Journal of solid state chemistry》2006,179(6):1681-1689
A series of 3D heteropolymolybdates, (NH4)2{[M(H2O)3]2[TeMo6O24]}·H2O (M=Mn(1), Co(2), Ni(3), Cu(4), and Zn(5)) and [Ln(H2O)4]2[TeMo6O24]·3H2O (Ln=La(6), Ce(7), and Nd(8)), has been isolated from hydrothermal reactions and characterized by elemental analyses, IR spectra, X-ray crystallography and magnetic properties. Single-crystal X-ray diffraction analysis reveals that compounds 1-8 possess unusual (3,6)-connected networks constructed from Anderson-type anions [TeMo6O24]6− and transion metal or rare-earth metal cations. Compounds 1-5 are of highly symmetrical structures with pyrite-like topology in which [TeMo6O24]6− anions act as 6-connected sites and transition metal cations act as 3-connected sites. Compounds 6-8 crystallize in symmetrical space groups lower than that of 1-5 exhibiting rutile-like topology with [TeMo6O24]6− anions acting as 6-connected sites and rare-earth metal cations acting as 3-connected sites. The magnetic properties of 1-4 are also presented. 相似文献
9.
Bao Li 《Journal of solid state chemistry》2008,181(12):3337-3343
Three polyoxotungstates, Na8[Cu(H2O)2(H2W12O42)]·30H2O (1), Na8[Cd(H2O)2(H2W12O42)]·20H2O (2), and Na7.4[Cd1.3(H2O)2(H2W12O42)]·24H2O (3), were synthesized and characterized by elemental and thermogravimetric (TG)analysis, infrared spectroscopy and X-ray single-crystal analysis. Both complexes 1 and 2 exhibit one-dimensional structure with two neighboring paradodecatungstate-B clusters, [H2W12O42]10−, linked by [Cu(H2O)2]2+ or [Cd(H2O)2]2+ units, while complex 3 displays a two-dimensional network structure. The electrochemical behaviors of complexes 1 and 3 were investigated in the buffer solution of pH 4.8. The results of electrocatalysis reveal that the reduced species of complexes 1 and 3 are electrocatalytically active for the reduction of nitrite. Complex 1 exhibits the electrocatalytic activity for the reduction of nitrate as well. The surface photovoltage spectroscopy (SPS) and electric field-induced SPS (EFISPS) measurements show that the surface photovoltage behavior of complex 1 is complicated while complex 3 bears the property of n-type semiconductor. 相似文献
10.
Two new hybrid compounds based on Keggin-type polyoxometalates: {[PMo12O40][Ni(Phen)2(H2O)]2}·K·2OH− (1) and [Cd2(Phen)4Cl2][HPW12O40]·H2O (2) (Phen=1,10-phenanthroline), have been prepared and characterized by IR, UV-vis, XPS, XRD and single crystal X-ray diffraction analyses. Compound 1 exhibits a 1-D chain structure constructed from Pseudo-Keggin polyoxometalate bi-supported transition metal coordination complexes linked by K+ ions. Compound 2 contains Pseudo-Keggin polyoxoanions [HPW12O40]2− and novel metal-chloride-ligand coordination complexes [Cd2(Phen)4Cl2]2+. 相似文献
11.
Konstantina A. Kounavi Constantina Papatriantafyllopoulou Anastasios J. Tasiopoulos Spyros P. Perlepes Vassilios Nastopoulos 《Polyhedron》2009
An investigation of the MII/X−/L [MII = Co, Ni, Cu, Zn; X− = Cl−, Br−, I−, NCS−, NO3−, N3−, CH3COO−; L = 1-methyl-4,5-diphenylimidazole] general reaction system towards the detailed study of the intermolecular interactions utilized for controlling the supramolecular organization and the structural consequences on the structures produced has been initiated. Three representative complexes with the formulae [Co(NO3)2(L)2] (1), [Zn(NO3)2(L)2] (2) and [Co(NCS)2(L)2]·EtOH (3·EtOH) have been synthesized and characterized by spectroscopic methods and single-crystal X-ray analysis. Compounds 1 and 2 are isomorphous (tetragonal, I41cd) with their metal ions in a severely distorted octahedral Co/ZnN2O4 environment, while 3·EtOH crystallizes in P21/c with a tetrahedral CoN4 coordination. The structural analysis of 1, 2 and 3·EtOH reveals a common mode of packing among neighbouring ligands (expressed through intramolecular π–π interactions between the 4,5-diphenylimidazole moieties), enhancing thus the rigidity and stability of the complexes. The bent coordination of the two isothiocyanates in 3 [Co–NCS angles of 173.8(2) and 160.8(2)°] seems to be caused by intermolecular hydrogen bonding and crystal packing effects. 相似文献
12.
Shin-ichi NayaMakoto Nitta 《Tetrahedron》2003,59(37):7291-7299
Uracil-annulated heteroazulenes, 6-substituted 7,9-dimethylcyclohepta[b]pyrimido[5,4-d]pyrrole-8(7H),10(9H)-dionylium tetrafluoroborates 7a,b·BF4−, which are the isoelectronic compounds of 5-dezazaflavin, were synthesized. X-Ray crystal analysis and MO calculations were carried out to clarify the structural characteristics of 7a,b·BF4−. The stability of cations 7a,b is expressed by the pKR+ values which were determined spectrophotometrically to be 10.9 and 11.2, respectively. The electrochemical reduction of 7a,b exhibited high reduction potentials at −0.84 and −0.87 (V vs Ag/AgNO3) upon cyclic voltammetry (CV). A good linear correlation between the pKR+ values and reduction potentials (E1red) of 7a,b·BF4− and reference compounds 4·BF4− and 5·BF4− was obtained. In a search of the reactivity, reactions of 7a,b·BF4− with some nucleophiles, hydride and diethylamine, were carried out to clarify that the introduction of nucleophiles to give regio-isomers is dependent on the nucleophile. The photo-induced oxidation reactions of 7a,b·BF4− toward some alcohols under aerobic conditions were carried out to give the corresponding carbonyl compounds in more than 100% yield [based on compounds 7a,b·BF4−], suggesting the oxidizing function of 7a,b·BF4− toward alcohols in the autorecycling process. 相似文献
13.
The reactions of LnCl3·6H2O (Ln=Eu or Dy) and Na2[Mo2O3S(HNTA)2]·6H2O afford Na[Mo2O3S(HNTA)2]2·Eu(H2O)9·3H2O (1) (NTA=nitrilotriacetate) and Na{(H2O)6Dy[Mo2O3S(HNTA)2]2}·7.5H2O (2), respectively. The [Mo2O3S(HNTA)2]2− cluster units of 1 are interconnected by Na+ into a 3-D open framework with rutile topology templated by . The coordination of [Mo2O3S(HNTA)2]2− to the slightly smaller Dy3+ ion of greater ionic potential as a consequence of lanthanide contraction has been observed to form the pentanuclear heterometallic {Dy(H2O)6[Mo2O3S(HNTA)2]2}−, which is linked by Na+ and hydrogen bonds between the protonated carboxylate groups into a 3-D supramolecular framework. The weak antiferromagnetic interactions between the Dy3+ ions of 2 have been observed. 相似文献
14.
Yuanzhe Gao Yanqing Xu Zhangang Han Chunhong Li Yingnan Chi 《Journal of solid state chemistry》2010,183(5):1000-1006
Inorganic-organic hybrid frameworks, namely [Ce(H2O)3(pdc)]4[SiW12O40]·6H2O 1, [M(H2O)4(pdc)]4[SiW12O40]·2H2O (M=Ce for 2a, La for 2b, Nd for 2c; H2pdc=pyridine-2,6-dicarboxylic acid) were assembled through incorporation of Keggin-type heteropolyanion [SiW12O40]4− within the voids of lanthanides-pdc network as pillars or guests under hydrothermal condition. Single-crystal X-ray analyses of these crystals reveal that compound 1 presents 3D pillar-layered framework with the [SiW12O40]4− anions located on the square voids of the two-dimensional Ce-pdc bilayer. Compounds 2a-c are isostructural and constructed from 3D Ln-pdc-based metal-organic framework (MOF) incorporating noncoordinating guests Keggin structure [SiW12O40]4−. Solid-state properties of compounds 1 and 2a-c such as thermal stability and photoluminescence have been further investigated. 相似文献
15.
Chomchai Suksai Disyaphong Jainuknan Nongnuch Muangsin Palangpol Kongsaeree 《Tetrahedron letters》2005,46(16):2765-2769
The heteroditopic receptor 2 containing a crown ether and amidoferrocence groups was synthesized and the binding abilities with various anions are reported in the presence and absence of metal cations. In the presence of Na+, 2 showed positive co-operative binding towards Br− with the binding affinity Kass = 16,096 M−1. Therefore, receptor 2 showed a switched-on binding for Br− in the presence of Na+ and a switched-off binding in the absence of Na+. Compound 2 was also found to sense Cl− and Br− electrochemically. 相似文献
16.
Rosa Carballo Berta CoveloNuria Fernández-Hermida Emilia García-MartínezAna Belén Lago Ezequiel M. Vázquez-López 《Polyhedron》2008
The reaction of CuSO4 · H2O with 4-bpytm [4-bpytm = bis(4-pyridylthio)methane] in EtOH afforded the complex [Cu(SO4)(4-bpytm)(H2O)3] · H2O (1 · H2O) while the reaction of 4-bpytm with Cu(NO3)2 · 3H2O in EtOH afforded the complex [Cu(NO3)2(4-bpytm)2] · H2O (2 · H2O). The reaction of 4-bpytm with Cu(NO3)2 · 3H2O in EtOH/dmf under microwave irradiation afforded the pseudo-polymorph [Cu(NO3)2(4-bpytm)2] · Solv (2 · Solv). Compound 1 · H2O forms helical chains while compounds 2 · H2O and 2 · Solv are 2D coordination polymers with a (4,4) topology based on rhombic grids in 2 · H2O and on a parquet motif in 2 · Solv. The 3D supramolecular organization through hydrogen bonding is analyzed for the three compounds and their thermal behaviour was also investigated. 相似文献
17.
Ying Liu Rui-Ge Cao Hong-Mei Ji Shi-Wei Zhang Yuan-Hang Ren 《Journal of solid state chemistry》2008,181(9):2237-2242
Two compounds, {[Sm(H2O)5]2(TeMo6O24)}·6H2O (1) and {[Eu(H2O)7]2 (TeMo6O24)}·5H2O (2) have been synthesized by hydrothermal reactions and characterized by elemental analyses, IR spectra, thermal stability analyses, X-ray powder diffraction, and single-crystal X-ray diffraction. Compound 1 represents the first example of a 2D layer architecture constructed from Anderson-type polyoxoanions [TeMo6O24]6− and rare-earth ions Ln3+. Compound 2 displays a 1D chain structure built up of alternating Anderson-type polyoxoanions [TeMo6O24]6− and rare-earth ions Eu3+ along the c-axis. Luminescence measurement of 2 exhibits typical red fluorescent emission of the Eu3+ ion at room temperature. Furthermore, the emission is intense enough to be observed macroscopically under UV irradiation (365 nm). 相似文献
18.
Abolghasem BakhodaNasser Safari Vahid AmaniHamid Reza Khavasi Mahin Gheidi 《Polyhedron》2011,30(17):2950-2956
Homo bi-copper complexes [Cu2{PhP(2-py)2}2(NO3)3] (1) and [Cu2{P(2-py)3}2Cl2] (2), were synthesized from the reaction of Cu(NO3)2·3H2O and CuCl2·2H2O with their corresponding 2-pyridylphosphine ligands. Compound 1 has a mixed valence Cu(I)-Cu(II) core with electron acceptor phosphine atoms and two NO3− anions coordinated in a monodentate fashion to Cu(I), giving it a distorted tetrahedral geometry. The environment of Cu(II) in 1 is composed of four nitrogen atoms from pyridyl and another NO3− anion in a square pyramidal geometry. This complex shows luminescence and a low energy absorption band at 969 nm corresponding to intermetallic electron transfer between the copper centers. Complex 2 was prepared from the treatment of copper(II) chloride with tris(2-pyridyl)phosphine, producing a binuclear copper complex which possesses a crystallographic inversion center. The copper geometry in this complex is distorted tetrahedral with coordination of one Cl−, two nitrogens from one bridging tris(2-pyridyl)phosphine ligand and one P atom from the other bridging tris(2-pyridyl)phosphine ligand, in a similar way observed in related complexes. The products have been characterized by spectroscopic methods and also by the single-crystal X-ray diffraction method. 相似文献
19.
Jing-An Zhang Mei Pan Rui Yang Zhi-Gang She Wolfgang Kaim Zhi-Jin Fan Cheng-Yong Su 《Polyhedron》2010
The semirigid tridentate 8-(2-pyridinylmethylthio)quinoline ligand (Q1) is shown to form the structurally characterized transition metal complexes [Cu(Q1)Cl2] (1), [Co(Q1)(NO3)2] (2), [Cd(Q1)(NO3)2] (3), [Cd(Q1)I2] (4). [Cu(Q1)2](BF4)2·(H2O)2 (5), [Cu(Q1)2](ClO4)2·(CH3COCH3)2 (6), [Zn(Q1)2](ClO4)2(H2O)2 (7), [Cd2(Q1)2Br4] (8), [Ag2(Q1)2(ClO4)2] (9), and [Ag2(Q1)2(NO3)2] (10). Four types of structures have been observed: ML-type in complexes 1–4, in which the anions Cl−, NO3− or I− also participate in the coordination; ML2− type in complexes 5–7 without direct coordination of the anions BF4− or ClO4− and with more (Cu2+) or less (Zn2+) distorted bis-fac coordinated Q1; M2L2-type in complex 8, in which two Br− ions act as bridges between two metal ions; and M2(μ-L)2-type in complexes 9 and 10, in which the ligand bridges two anion binding and Ag–Ag bonded ions. Depending on electron configuration and size, different coordination patterns are observed with the bonds from the metal ions to Npyridyl longer or shorter than those to Nquinoline. Typically Q1 acts as a facially coordinating tridentate chelate ligand except for the compounds 9 and 10 with low-coordinate silver(I). Except for 6 and 8, the complexes exhibit distinct constraining effects against both G(+) and G(-) bacteria. Complexes 1, 3, 4, 5, 7 have considerable antifungal activities and complexes 1, 5, 7, and 10 show selective effects to restrain certain botanic bacteria. Electrochemical studies show quasi-reversible reduction behavior for the copper(II) complexes 1, 5 and 6. 相似文献
20.
Sanping Chen 《Journal of solid state chemistry》2008,181(12):3308-3316
An array of 2D isoreticular layers, viz. [Zn(atrz)X]∞ (1·X; X=Cl−, Br−, I−; atrz=3-amino-1,2,4-triazole anion), [Zn4(atrz)4(SCN)4·H2O]∞ (1·SCN·H2O) and [Zn(trz)X]∞ (2·X; X=Cl−, Br−, I−; trz=1,2,4-triazole anion), have been hydrothermally synthesized and structurally characterized. Compounds 1·X and 1·SCN·H2O are constructed from binuclear planar Zn2(atrz)2 subunits and exhibit (4,4) topological network when the subunits are simplified as four-connected nodes. Based on changing the terminal counteranions X (X=Cl−, Br−, I−, SCN−), the average interlayer separations of 1·X and 1·SCN·H2O are enlarged, which equal to 5.851, 6.153, 6.651 and 8.292 Å, respectively. As a result, H2O molecules reside in the spaces between two adjacent layers of 1·SCN·H2O. 2 and 1 are the isomorphous structures. In common with 1, the interlayer separations of 2·X are widened with increasing the ion radius. Solid-state luminescence properties and thermogravimetric analyses of 1 and 2 were investigated, respectively. 相似文献