共查询到20条相似文献,搜索用时 15 毫秒
1.
Masayoshi Onishi Koh-hei Kayano Hitoshi Yamaguchi Yasuhiro Arikawa 《Inorganica chimica acta》2004,357(14):4091-4101
Although reactions of samarium(III) chloride, SmCl3 · 6H2O, with potassium hydrotris(1-pyrazolyl)borate K[BH(pz)3] (pz = 1-pyrazolyl) in a molar ratio of (1/1) in THF afford [SmCl{BH(pz)3}2(Hpz)], similar reactions with K[B(pz)4] gave rise to separation of anhydrous H[B(pz)4]. The homoleptic eight-coordinate complex [Sm{B(pz)4}3] obtained from SmCl3 · 6H2O and threefold moles of K[B(pz)4] was allowed to react with twofold moles of K[BH(pz)3] to give a mixture of three major species [Sm{B(pz)4}n{BH(pz)3}(3 − n)] (n = 2, 1, 0), whereas similar reactions of [Sm{BH(pz)3}3] with K[B(pz)4] did not proceed at all. The acetylacetonato (acac) complex [Sm{B(pz)4}2(acac)], derived from the triflate “Sm{B(pz)4}2(OTf)”, was treated with twofold moles of K[BH(pz)3] and showed its quantitative conversion to [Sm{BH(pz)3}2(acac)]. However, analogous reaction of [Sm{BH(pz)3}2(acac)] with K[B(pz)4] did not proceed. Accordingly, samarium(III) ion was determined to prefer coordination of BH(pz)3 ligand to that of B(pz)4, indicating less σ-donating electronic character of the latter. The complexes [Sm{B(pz)4}2(L-L)] (L-L = β-ketoenolato) in toluene-d8 exhibited 1H NMR spectroscopic equivalence of all four pyrazolyl groups at high temperatures, and are regarded as a new class of B(pz)4 complexes, showing fast intramolecular exchange of their coordinated and uncoordinated pyrazolyl groups. Four compounds were crystallographically characterized. 相似文献
2.
Augusto CingolaniEffendy Domenico MartiniMaura Pellei Claudio Pettinari Brian W. SkeltonAllan H. White 《Inorganica chimica acta》2002,328(1):87-95
The reaction of AgX (X=ClO4, NO3 or SO3CH3) acceptors with excesses of tris(pyrazol-1-yl)methane ligands L (L=CH(pz)3, CH(4-Mepz)3, CH(3,5-Me2pz)3, CH(3,4,5-Me3pz)3 or CH(3-Mepz)2(5-Mepz)) yields 1:1 [AgX(L)], 2:1 [Ag(L)2]X or 3:2 [(AgX)2(L)3] complexes. The ligand to metal ratio in all complexes is dependent on the number and disposition of the Me substituents on the azole ring of the neutral ligand and on the nature of the Ag(I) acceptor. All complexes have been characterized in the solid state as well as in solution (medium- and far-IR, 1H and 13C NMR and conductivity determinations) and the solid-state structures of [Ag(NO3){(pz)3CH}](∞/∞) and [Ag{(3,5-Me2pz)3CH}2]NO3 determined by single crystal X-ray studies. 相似文献
3.
Ling Huang Kevin J. Seward B. Patrick Sullivan Wayne E. Jones John J. Mecholsky Walter J. Dressick 《Inorganica chimica acta》2000,310(2)
We describe the synthesis, characterization, and reactivity of several Ru(II) complexes of the type cis-L2Ru(Z)n+, where L is an α-diimine [e.g. 2,2′-bipyridine (bpy) or 1,10-phenanthroline (phen)] ligand and Z is a bis-coordinated scorpionate ligand such as tris-(1-pyrazolyl)methane (HC(pz)3, PZ=1-pyrazolyl; n=2) or tetrakis-(1-pyrazolyl)borate anion (B(pz)4 −; n=1). The complexes each exhibit strong visible absorption assigned as a π*(L)←dπ(Ru) metal-to-ligand charge-transfer (MLCT) transition characteristic of the cis-L2Ru2+ kernel. A corresponding MLCT excited state emission is observed in room temperature CH3CN solution, although emission energies, lifetimes, and quantum yields are reduced relative to Ru(bpy)3 2+. Electronic spectra and cyclic voltammetry measurements indicate that the relative π-acceptor abilities of the coordinated Z are: Z=(1H-pyrazolyl)2(pz)2B(pz)2<(pyridine)2<(pz)2CH(pz). Uncoordinated pz groups of cis-(bpy)2Ru(pz)2B(pz)2 + can be reacted to form a sterically hindered, localized-valence (Kcom33 l mol−1) cis,cis-(bpy)2RuII(pz)2B(pz)2RuII(bpy)2 3+ dimer. The dimer properties are interpreted by comparison to the known cis-(bpy)2RuII(pz)2RuII(bpy)2 2+ analog. The dimer is photoreactive and undergoes an asymmetrical photocleavage in CH3CN (yielding cis-(bpy)2RuIII(pz)2B(pz)2 2+ and cis-(bpy)2RuII(CH3CN)2 2+), similar to the corresponding thermal reaction observed for the mixed-valence cis-(bpy)2RuII(pz)2RuIII(bpy)2 3+ system. 相似文献
4.
Allan J. Canty Jim PatelMichel Pfeffer Brian W. SkeltonAllan H. White 《Inorganica chimica acta》2002,327(1):20-25
Neutral palladium(IV) complexes containing the bis(pyrazol-1-yl)borate ligand, PdMe3{(pz)2BH2}(L) [L=py-d5 (4), PMe2Ph (6)], are generated in solution by oxidative addition of iodomethane to [PdMe2{(pz)2BH2}]− at −70 °C followed by addition of L; the Pd(IV) complexes reductively eliminate ethane above 0 °C. Stable Pt(IV) analogues of 4 and 6 have been isolated, and comparison of NMR spectra for Pd(IV) and Pt(IV) species support structural assignments for the unstable Pd(IV) complexes. The complex PtMe3{(pz)2BH2}(py) (1a) has been characterised by X-ray diffraction, together with Pt(mq)Me2{(pz)2BH2} (2) (mq=8-methylquinolinyl); both complexes show a fac-PtC3 configuration for Pt(IV), and for 2 the PtN distances are ∼0.03 Å shorter than in the isostructural Pd(IV) complex. 相似文献
5.
Domenico MartiniMaura Pellei Claudio Pettinari Brian W. SkeltonAllan H. White 《Inorganica chimica acta》2002,333(1):72-82
The reaction between CuX2 (X=ClO4, NO3, Cl, Br and CH3COO) and excess of tris(pyrazol-1-yl)methane ligands L (L=CH(pz)3, CH(4-Mepz)3, CH(3,5-Me2pz)3, CH(3,4,5-Me3pz)3 or CH(3-Mepz)2(5-Mepz)) yields [CuX2(L)], [{CuX2}3(L2)2] or [Cu(L2)]X2-type complexes. The ligand to metal ratio is dependent on the number and disposition of the Me substituents on the azole-type ligand and mainly on the nature of the counter-ion X. All complexes have been characterized in the solid state as well as in solution (IR and UV spectra, and conductivity determinations). The solid-state structures of [Cu{(3,5-Me2pz)3CH}2](NO3)2, [Cu{(3,5-Me2pz)3CH}2](ClO4)2·0.5H2O, [Cu{(3,4,5-Me3pz)3CH}2](NO3)2·H2O, [Cu{(4-Mepz)3CH}2]Br2·3H2O have been determined by single crystal X-ray studies. 相似文献
6.
The mono- and dinuclear base-stabilized gold(I) pyrazolate complexes, (PPh3)Au(μ-3,5-Ph2pz)) (1), (TPA)Au(3,5-Ph2pz), TPA=1,3,5-triaza-7-phophaadamantane (2), [(PPh3)2Au(μ-3,5-Ph2pz)]NO3 (3) and [(dppp)Au(μ-3,5-Ph2pz)]NO3, dppp=bis(diphenylphosphino)propane (4), have been synthesized and structurally characterized. The mononuclear gold(I) complexes 1 and 2 show intermolecular Au?Au interactions of 3.1540(6) and 3.092(6) Å, while the dinuclear gold(I) complexes 3 and 4 show an intramolecular Au?Au distances of 3.3519(7) and 3.109(2) Å, respectively, typical of an aurophilic attraction. Complexes 1-4 exhibit luminescence at 77 K when excited with ca. 333 nm UV light with an emission maximum at ca. 454 nm. The emission has been assigned to ligand-to-metal charge transfer, LMCT, based upon the vibronic structure that is observed. 相似文献
7.
High-temperature spin-crossover in coordination compounds of iron(II) with tris(pyrazol-1-yl)methane
O.G. Shakirova V.A. Daletsky T.P. Griaznova V.V. Syakaev 《Inorganica chimica acta》2010,363(14):4059-4064
Novel mononuclear Fe(II) complexes of tris(pyrazol-1-yl)methane [Fe{HC(pz)3}2]2+ with and p-sulfonatothiacalix[4]arene (TCAS4−) as counterions were obtained. The compounds were characterized by magnetic susceptibility method, IR and UV-Vis spectroscopy. The structure of [Fe{HC(pz)3}2]SiF6 has been analyzed by single-crystal X-ray diffraction. The 1H NMR spectroscopy measurements of [Fe{HC(pz)3}2]2(TСAS) in aqueous solution reveal the outer sphere inclusion of [Fe{HC(pz)3}2]2+ into the cyclophanic cavity of TCAS4−. The temperature induced spin-crossover 1А1 ⇔ 5Т2, accompanied by thermochromism, has been revealed from the temperature dependence of μeff and IR spectra for both complexes. The comparative analysis of magnetochemical and spectroscopy data elucidates the effect of the cyclophanic counterion on the physico-chemical properties of Fe(II) complex. 相似文献
8.
The complexes of lanthanide shift reagents (LSR) with permethylated aldo-hexopyranosides and their 6-deoxy analogues having the gluco, galacto, and manno configurations have been studied. On the basis of shift data from Eu(fod)3 and Pr(fod)3, and broadening data from Gd(fod)3, it was found that the LSR bind preferentially to two neighbouring MeO-oxygens having the axial-equatorial relationship. Because of its steric requirements, the C-5 substituent hinders the binding increasingly in the following order: O-2(ax)-O-3(eq)<O-1(ax)-O-2(eq)<O-4(ax)-O-3(eq). Equatorial groups bind the LSR only weakly. Strong binding to O-6 was found when MeO-6 is predominantly “axially” oriented; when this group has the “equatorial” position, O-6 is not favoured over any other equatorial oxygen. In view of the preference of the LSR to bind to an O(ax)-O(eq) site, it is proposed that O-5 is involved in the binding to the axial O-6. Eu(fod)3 seems to have less tendency to bind to the O-6(ax)-O-5 site than the other two LSR. 相似文献
9.
Miguel-Ángel Muñoz-Hernández Author Vitae Virginia Montiel-Palma Author Vitae 《Inorganica chimica acta》2009,362(12):4328-9212
Heavy group 13 and 14 analogs of the poly(pyrazolyl)borates are the subject of this review. Within these, the most extensive research has been performed on the study of polypyrazolylgallates Me2Ga(R2pz)2]− (R = H or Me) and [MeGa(pz)3]−, and their complexes with transition metals. In this review, the common features shared with the boron analogs are presented and contrasted. Other recently reported series of group 13 analogs are the alkali polypyrazolylaluminates Na[(R2pz)3] with R = Me, tBu; R′ = M. The complexes with one or two pyrazolyl ligands on aluminum display anagostic Al-CH3?Na interactions, these interactions are persistent even if complexes were obtained from solutions with THF that normally coordinate alkali ions. The polypyrazolylsilane ligands Me2Si(R2pz)2 and MeSi(R2pz)3 with R = H, Me are remarkably easy to obtain and isolate, in contrast is the fact that the carbon analogs are much harder to obtain and isolate in reasonable yields. Therefore it is surprising that the chemistry of the former ligands is not as developed as could be anticipated. Nevertheless there are examples of the use of these silanes as ligands with the following transition metals: Cr, Mn, Cu, Zn, Sc and Zr. The heavier group 14 analogs with Ge and Sn display coordination patterns with alkali and alkaline ions that resemble those observed with the borates and aluminates. The formation of cationic bimetallic cages of the type [E2(R2pz)3]+ and neutral complexes [E2(R2pz)4] has also been observed that can be consider formal isomers of the alkenes. The use of these compounds as ligands has been recently reported. 相似文献
10.
《Inorganica chimica acta》1988,148(1):101-104
The compound In[(pz)2BH2]3 (pz = 1-pyrazolyl, C3H3N2−) was prepared from In(NO3)3 and K[(pz)2-BH2] in water, and characterised by spectroscopic and X-ray methods. Crystals are orthorhombic,Pna21,a = 20.279(4),b = 8.884(2),c = 13.411(2)Å;R = 0.0285. Individual molecules contain a near-regular six-coordinate indium atom with In–N (av.) 2.241(5)Å. The pyrazolyl borate ligands are puckered, with dihedral angles between the two rings of each ligand in the range 133–144°. 相似文献
11.
The complexes of Eu(fod)3 with per-O-methylated aldohexosylaldohexoses, consisting of d-glucopyranose and d-galactopyranose residues and having (1→2), (1→4), and (1→6) linkages, have been studied by using p.m.r. spectroscopy. It was found that Eu(fod)3 binds preferentially to two neighbouring MeO-oxygens having an axial-equatorial relationship. Steric hindrance is a major factor in disfavouring certain sites. On the basis of Eu(fod)3-effects on the methoxyl groups, and the comparison of the chemical shifts of corresponding groups in the permethylated mono- and di-saccharides, the signals for most of the Meo groups of the latter compounds were assigned. The shift increments of the signals for these MeO groups, with respect to those for the corresponding groups in the permethylated monomers, were related to the type and the configuration of the inter-sugar linkage. The potential of the shift increments for assignment purposes in other permethylated di- or higher-saccharides is discussed. 相似文献
12.
Kerstin Kunz 《Inorganica chimica acta》2009,362(12):4372-4376
The new phenyl/scorpionate hybrid ligand [Ph(pz)BC5H10]− has been synthesised and structurally characterised as K+ and Tl+ salt. The ligand is specifically designed to create half-sandwich complexes in which the metal ion is chelated by the π-electron system of the phenyl ring and by the electron lone pair of the pyrazolyl nitrogen atom. This structural motif is established both by K[Ph(pz)BC5H10] and by Tl[Ph(pz)BC5H10]. 相似文献
13.
The [ReOX3(AsPh3)(OAsPh3)] (X = Cl or Br) complexes react with two equivalents of 3,5-dimetylopyrazole (3,5-Me2pzH) in acetone at room temperature to give [{Re(O)X2(3,5- Me2pzH)2}2(μ-O)] (1 and 2). In the case of [ReOBr3(AsPh3)(OAsPh3)], a small quantity of the dinuclear rhenium complex [{Re(O)Br(3,5-Me2pzH)}2(μ-O)(μ-3,5-Me2pz)2] (3) has been isolated next to the main product 2. Treatment of [ReOX3(PPh3)2] compounds with two equivalents of 3,5-Me2pzH in acetone at room temperature leads to the isolation of symmetrically substituted dinuclear rhenium complexes [{Re(O)X(PPh3)}2(μ-O)(μ-3,5-Me2pz)2] (4 and 5). Refluxing of [ReO(OEt)X2(PPh3)2] complexes with 3,5-Me2pzH in ethanol affords unsymmetrically substituted dinuclear rhenium [{Re(O)X(PPh3)}(μ-O)(μ-3,5-Me2pz)2{Re(O)X(3,5- Me2pzH)}] complexes (6 and 7). The complexes obtained in these reactions have been characterised by IR, UV-Vis, 1H and 31P NMR. The crystal and molecular structures have been determined for 1, 2, 3, 4, 6 and 7 complexes. 相似文献
14.
Two dinuclear palladium(II) complexes, [{Pd(en)Cl}2(μ-pz)](NO3)2 and [{Pd(en)Cl}2(μ-pydz)](NO3)2, have been synthesized and characterized by elemental microanalysis and spectroscopic (1H and 13C NMR, IR and UV–vis) techniques (en is ethylenediamine; pz is pyrazine and pydz is pyridazine). The square planar geometry of palladium(II) metal centers in these complexes has been predicted by DFT calculations. The chlorido complexes were converted into the corresponding aqua complexes, [{Pd(en)(H2O)}2(μ-pz)]4+ and [{Pd(en)(H2O)}2(μ-pydz)]4+, and their reactions with N-acetylated l-histidylglycine (Ac–l–His–Gly) and l-methionylglycine (Ac–l–Met–Gly) were studied by 1H NMR spectroscopy. The palladium(II)-aqua complexes and dipeptides were reacted in 1:1 M ratio, and all reactions performed in the pH range 2.0 < pH < 2.5 in D2O solvent and at 37 °C. In the reactions of these complexes with Ac–l–His–Gly and Ac–l–Met–Gly dipeptides, the hydrolysis of the amide bonds involving the carboxylic group of both histidine and methionine amino acids occurs. The catalytic activities of the palladium(II)-aqua complexes were compared with those previously reported in the literature for the analogues platinum(II)-aqua complexes, [{Pt(en)(H2O)}2(μ-pz)]4+ and [{Pt(en)(H2O)}2(μ-pydz)]4+. 相似文献
15.
《Inorganica chimica acta》1988,154(1):95-97
Aerial recrystallization of the mononuclear molybdenum(V) complex {HB(Me2pz)3}MoO(OC6H4-o-S) produced the novel binuclear Mo(VI) complex [{HB(Me2pz)3}MoO2(OC6H4- o-S)]2 which contains a disulfide bond. The dimer crystallizes as the dioxane solvate in the space group C2/c with cell parameters a=23.46(2), b=11.100(4), c=21.571(8) Å, β=104.23(4)°, Z=4. Final Rw=0.062 (2236 reflections with Fo>3σ(Fo), 301 variable parameters). The dimer contains two crystallographically identical distorted octahedral MoO22+ centers. One face of each octahedron is occupied by two oxo ligands and a phenolate oxygen atom; the opposite face is occupied by three nitrogens of the HB(Me2pz)3− ligand. The two Mo(VI) centers of the dimers are linked by a disulfide bond formed upon oxidation of the 2-mercaptophenolate ligand of the original molybdenum(V) compound. 相似文献
16.
Yttrium is stoichiometrically doped into europium by mole percentage, during the synthesis of Y(1‐x)Eu(x)(TTA)3(Phen), using solution techniques (where x = 0.2, 0.4, 0.5, 0.6 and 0.8, TTA = thenoyltrifluoroacetone and Phen = 1,10‐phenanthroline).These complexes were characterized using different techniques such as X‐ray diffraction, thermogravimetric/differential thermal analysis, optical absorption and emission spectra. Thin films of the doped Eu–Y complexes were prepared on a glass substrate under a high vacuum of 10‐6 Torr. The photoluminescence spectra of these thin films were recorded by exciting the sample at a wavelength of 360 nm. The emission peak for all the synthesized complexes centered at 611 nm; maximum emission intensity was obtained from Y0.6Eu0.4 (TTA)3(Phen). The results proved that these doped complexes are more economical than pure Eu(TTA)3(Phen) and are best suited as red emissive material for energy‐efficient and eco‐friendly organic light‐emitting diodes and displays. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
17.
A modification of the diketonate method for the determination of the absolute configuration of chiral vicinal diols, first proposed by Nakanishi, is taken under object and tested with a set of aliphatic and aromatic substrates; Yb(fod)(3) (fod = 6,6,7,7,8,8,8-heptafluoro-2,2-dimethyl-3,5-octanedionate) is employed as the chromophoric species. The replacement of dpm (dpm = dipivalomethanate) with fod ensures the formation of strong and stable signals in the UV region, whose signs are related to the configuration of the chelating molecule. The choice of ytterbium as the central cation introduces two major advantages: the electronic f-f transition of the rare-earth supplies a second spectral window in the near-IR, which is sensitive to the chemical environment around the atom. This allowed us to ascertain the number of different species present in solution and the observation of an induced CD also for strongly UV-absorbing substrates. The pseudocontact shifts induced in the (1)H-NMR spectrum by the unpaired electron of the lanthanide ion provide valuable structural information on the adducts. 相似文献
18.
The new bis(pyrazolyl)amine ligand NH2CH2CH(pz)2 (1) was prepared from the reaction of N-[2,2-bis(pyrazolyl)ethyl]-1,8-naphthalimide with hydrazine monohydrate. A substituted derivative, C6H5CH2NHCH2CH(pz)2 (2), was prepared by the reaction of 1 with benzaldehyde followed by reduction with NaBH4. Ligand 1 was also converted by two methods to the new bitopic, para-linked bis(pyrazolyl)amine ligand p-C6H4(CH2NHCH2CH(pz)2)2, (3). The reactions of the ligands 1-3 with [Cu(PPh3)2]NO3 yields {(PPh3)Cu[(pz)2CHCH2NH2]}NO3, {(PPh3)Cu[(pz)2CHCH2NHCH2C6H5]}NO3 and {[(PPh3)Cu]2[p-((pz)2CHCH2NHCH2)2C6H4]}(NO3)2·solvate, respectively. Complex {(N3)2Cu[(pz)2CHCH2NHCH2C6H5]} was obtained from a methanol solution of 2, copper(II) acetate monohydrate and sodium azide. The complex {Cd[(pz)2CHCH2NHCH2C6H5]2}(PF6)2·3C3H6O was synthesized by reaction of the protonated form of ligand 2, [(pz)2CHCH2NH2CH2C6H5]PF6, with Cd(acac)2. In all of the structures the ligands are tridentate, bonding to the metal through the lone pair on the amine group as well as through the pyrazolyl rings - they act as true scorpionates. The solid state structures all have extensive non-covalent interactions, with the N-H functional groups of the amines participating in both N-H?π and N-H?O or N-H?N hydrogen bonding interactions. 相似文献
19.
Anders Lennartson 《Inorganica chimica acta》2011,365(1):451-453
Optical resolution of [M(acac)3] complexes, where acac− is the acetylacetonato ligand, was achieved decades ago for metal ions such as Co3+ and Cr3+, i.e. for metal ions forming configurationally inert complexes. Complete optical resolution of [Fe(acac)3] have so-far been unsuccessful due to the high rate of racemisation. By means of spontaneous resolution of its carbon tetrachloride solvate, we have been able to prepare optically pure samples of [Fe(acac)3]. These samples displayed circular dichroism in the solid state, as well as in diethyl ether solution, and the CD-spectra could be correlated to the correct absolute configuration. Using CD-spectroscopy, the optical half-life was estimated to be 3.3 min in diethyl ether solution at ambient temperature. In the same solvent, no sign of racemisation was observed after 23 h at −80 °C. Racemic [Fe(acac)3] is a useful catalyst in organic synthesis. 相似文献
20.
Xing Y Zhang Y Sun Z Ye L Xu Y Ge M Zhang B Niu S 《Journal of inorganic biochemistry》2007,101(1):36-43
Using vanadate, poly(1H-pyrazol-1-yl)borate and pyrazole as starting materials, two new neutral peroxovanadium(V) complexes with poly(1H-pyrazol-1-yl)borate, VO(O(2))(pzH)(HB(pz)(3))(1) and VO(O(2))(pzH)(B(pz)(4))(2), were synthesized successfully. Both complexes were characterized by elemental analysis, IR, UV-vis and NMR spectra. And the structure of complex 1 was determined by X-ray diffraction, which is somewhat relevant for haloperoxidase enzymes. Cytotoxic effects also are discussed on 3T3 cell proliferation. In the concentration range (0.1-100mumol), both complexes have an inhibiting cellular proliferation effect. When the cells cultivated with the complexes at high dose, the toxicity effect of both complexes is more and more predominant. 相似文献