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1.
Chetna Khosla 《Inorganica chimica acta》2011,369(1):19-31
Addition of excess trimethylphosphine and a halide source to a solution of W(CO)(acac)2(η2-L) (L = NCPh and OCMe2) leads to displacement of L and one acetylacetonate chelate to produce electron-rich, seven-coordinate complexes of the formula W(CO)(acac)(X)(PMe3)3 (X = Cl, Br, and I). Use of NaN3 instead of a halide source leads primarily to loss of carbon monoxide and dinitrogen, and protonation from adventitious water yields the cationic imido complex [W(NH)(acac)(PMe3)3]+. Heating [W(NH)(acac)(PMe3)3]+ in aromatic isocyanates at high temperature results in isocyanate insertion into the NH imido bond to form new C-N bonds. An alternate route to related imido complexes involves heating [W(O)(acac)(PMe3)3]+ with phenyl isocyanate at high temperatures to yield the substituted imido complex [W(NPh)(acac)(PMe3)3]+. 相似文献
2.
The trinuclear complexes [Ag(PR3)2]2[Ni(mnt)2] and [AgL]2[Ni(mnt)2] have been prepared by reactions of (NEt4)2[Ni(mnt)2] and Ag2SO4 with alkyl phosphines (PR3=P(CH3)3 (PMe3) for 1, P(C2H5)3 (PEt3) for 2 and P(C6H11)3 (PCy3) for 3), or with chelating diphosphines (L=1,1′-bis(diphenylphosphino)ferrocene (dppf) for 4 and bis(diphenylphosphino)methane (dppm) for 5). The structures of all the complexes have been determined by X-ray crystallography. Interactions between the [Ag(PR3)2]+ and [Ni(mnt)2]2− groups occur in compounds 1 and 2 with Ni---Ag distances of 3.063(4) and 2.9311(6) Å, respectively. Only one sulfur atom of each mnt ligand bridged [Ag(PR3)2]+ cations and [Ni(mnt)2]2− anions in compound 1 through 3 with Ag---S distances of about 2.7 Å. There is no interaction between Ag and Ni in compound 3 due to the flexibility of the cyclohexyl groups. Interactions between [AgL]+ and [Ni(mnt)2]2− groups also occur in compound 4 with a much shorter Ag---Ni distance of 2.7213(7) Å, while silver atoms and the NiS4 plane in compound 4 make a chair conformation with Ag---S distances of about 2.8 Å. In compound 5, dppm bridges two silver atoms, and interaction between silver atoms occurs at a distance of 2.9859(11) Å, and only one sulfur atom of mnt is used to bridge Ni and Ag atoms with Ag---S distances of 2.582(3) and 2.663(3) Å. 相似文献
3.
Rehan Basta 《Inorganica chimica acta》2004,357(13):3883-3888
The reactions of Zr(C5H5)(6,6-dmch)(PMe3)2 and Zr(6,6-dmch)2(PMe3)2 (dmch=dimethylcyclohexadienyl) with CO lead to the selective replacement of one PMe3 ligand by CO. Both carbonyl complexes have been structurally characterized. Additionally, the reaction of the latter complex with PhC2SiMe3 leads to a similar replacement of one PMe3 ligand, involving simple coordination of the alkyne, rather than any coupling to the dmch ligand. 相似文献
4.
The reactions of [(H5C6)3P]2ReH6− with (CH3CN)3Cr(CO)3, (diglyme)Mo(CO)3 or (C3H7CN)3W(CO)3 led to the formation of [(H5C6)3P]2ReH6M(CO)3− (M = Cr, Mo, W) complexes. These have been characterized by IR and NMR spectroscopies, as well as elemental analyses. A single crystal X-ray diffraction study has also been carried out for the M = Cr complex as a K(18-crown-6)+ salt. The complex crystallizes as a THF monosolvate in the monoclinic space group P21/n with a = 22.323(6), B = 9.523(2), C = 27.502(5) Å, β = 104.98(2)0 and V = 5648 Å3 for Z = 4. The Re---Cr separation is 2.5745(12) Å, and the two phosphine ligands are oriented unsymmetrically. Although the hydride ligands were not found, the presence of three bridging hydrides and a dodecahedral coordination geometry about rhenium could be inferred. Low temperature 1H and 31P NMR spectroscopic studies did not reveal the low symmetry of the solid state structure. 相似文献
5.
Roberto Della Pergola Alessandro Fumagalli Carlo Manassero Mirella Sansoni 《Inorganica chimica acta》2008,361(6):1763-1769
The two clusters [HFe5NiN(CO)14]2− (1) and [HFe4Ni2N(CO)13]2− (2) were obtained by reaction of [Fe4N(CO)12]− and [Ni6(CO)12]2− in refluxing MeCN and EtCN, respectively, along with other Fe-Ni mixed metal clusters. Their solid state structures were determined on the [PPh4]+ salts, and both have an octahedral metal cage, containing an interstitial nitrogen atom. The two Ni atoms in 2 are cis, with a Ni-Ni separation of 2.724(1) Å. The two anions have different stereochemistry of the carbonyl ligands: in 1, five CO’s are semi-bridging, and the remaining nine are terminal; in 2 there are three asymmetric bridging and ten terminal ligands (two for each iron and one for each nickel). The hydride ligands were located in the final difference maps, both bridging a Ni-Fe edge of the clusters but, thanks to the better quality of the diffraction data, the metal-hydrogen distances were refined only in 2. In this cluster, the Fe-H and Ni-H bond lengths are 1.77(2) and 1.79(2) Å, respectively. 相似文献
6.
Pavel A. Abramov Rita Hernandez-Molina Alexander V. Virovets Pedro Gili Vladimir P. Fedin 《Inorganica chimica acta》2010,363(13):3330-3337
Reaction of [Mo2O2(μ-S)2(H2O)6]2+ with Mo(CO)6 or metallic Mo under hydrothermal conditions (140 °C, 4 M HCl) gives oxido-sulfido cluster aqua complex [Mo3(μ3-S)(μ-O)2(μ-S)(H2O)9]4+ (1). Similarly, [W3(μ3-S)(μ-O)2(μ-S)(H2O)9]4+ (2) is obtained from [W2O2(μ-S)2(H2O)6]2+ and W(CO)6. While reaction of [Mo2O2(μ-S)2(H2O)6]2+ with W(CO)6 mainly proceeds as simple reduction to give 1, [W2O2(μ-S)2(H2O)6]2+ with Mo(CO)6 produces new mixed-metal cluster [W2Mo(μ3-S)(μ-O)2(μ-S)(H2O)9]4+ (3) as main product. From solutions of 1 in HCl supramolecular adduct with cucurbit[6]uril (CB[6]) {[Mo3O2S2(H2O)6Cl3]2CB[6]}Cl2⋅18H2O (4) was isolated and structurally characterized. The aqua complexes were converted into acetylacetonates [M3O2S2(acac)3(py)3]PF6 (M3 = Mo3, W3, W2Mo; 5a-c), which were characterized by X-ray single crystal analysis, electrospray ionization mass spectrometry and 1H NMR spectroscopy. Crystal structure of (H5O2)(Me4N)4[W3(μ3-S)(μ2-S)(μ2-O)2(NCS)9] (6), obtained from 2, is also reported. 相似文献
7.
Two new zincophosphites [C6H14N2]0.5[Zn(H2PO3)2] 1 and [C4H12N2]0.5[(CH3)2NH2][Zn2(HPO3)3] 2 have been solvothermally synthesized in mixed solvents of N,N-dimethylformamide (DMF) and 1,4-dioxane (DOA), respectively. Single-crystal X-ray diffraction analysis reveals that compound 1 exhibits a neutral inorganic chain formed by ZnO4 and HPO2(OH) units. Interestingly, the left- and right-handed hydrogen-bonded helical chains are alternately formed via the hydrogen-bonds between two adjacent chains. Compound 2 exhibits a layer structure with 4- and 12-MRs formed by ZnO4 and HPO3 units, in which two kinds of organic amine molecules both act as countercations to compensate the overall negative electrostatic charge of the anionic network. 相似文献
8.
Two new tetrahedral tungsten cyanide cluster compounds, [Cu(dien)]3[W4Te4(CN)12] · 9H2O (1) (dien=diethylenetriamine) and [Ni(en)(NH3)]3[W4Se4(CN)12] · 7.5H2O (2) (en=ethylenediamine), were synthesized by treating aqueous solutions of the saltlike cluster compound K6[W4Te4(CN)12] · 5H2O/K6[W4Se4(CN)12] · 6H2O with copper(II)/nickel(II) chloride in aqueous ammonia containing dien/en. The cyano-bridged layered coordination polymeric compounds were characterized by single-crystal X-ray diffraction analysis: monoclinic, space group P21 for 1; trigonal, space group for 2. Structures of 1 and 2 consist of infinite neutral layers of cluster components {W4Te4(CN)12}/{W4Se4(CN)12} connected, one another by {Cu(dien)} or {Ni(en)(NH3)} fragments, respectively. 相似文献
9.
M.S Papadopoulos P Bouziotis I.C Pirmettis C.P Raptopoulou A Terzis E Chiotellis 《Inorganica chimica acta》1999,290(2):2808-250
A novel five-coordinate rhenium(III)-thiolato complex, Re(SCH2C6H4OCH3-p)3(PPh3)2 has been isolated during the reaction of trans-ReOCl3(PPh3)2 with p-methoxybenzyl mercaptan. In the unexpected structure that was acquired, the central metal has undergone a reduction from Re(V) to Re(III). The five-coordinate Re(III) complex has been characterized by spectroscopic methods, elemental analysis and X-ray crystallography. X-ray crystallographic studies showed the coordination geometry around rhenium to be that of a trigonal bipyramid. The basal plane is defined by three sulfur atoms of the monodentate ligand, while the two apical positions are occupied by two phosphines of the precursor. 相似文献
10.
Jian-Qing Tao Zhi-Guo Gu Tian-Wei Wang Qiao-Fang Yang Jing-Lin Zuo Xiao-Zeng You 《Inorganica chimica acta》2007,360(15):4125-4132
Two new spin-crossover complexes, [Fe(Medpq)(py)2(NCS)2] · py · 0.5H2O (1) and [Fe(Medpq)(py)2(NCSe)2] · py (2) (Medpq = 2-methyldipyrido[3,2-f:2′,3′-h]-quinoxaline, py = pyridine), have been synthesized. The crystal structures were determined at both room temperature (298 K) and low temperature (110 K). Complexes 1 and 2 crystallize in the orthorhombic space group Pbca and monoclinic space group P21/n, respectively. In both complexes, the distorted [FeN6] octahedron is formed by six nitrogen atoms from Medpq, the trans pyridine molecules and the cis NCX− groups. The thermal spin transition is accompanied by the shortening of the mean Fe–N distances by 0.194 Å for 2. The mononuclear [Fe(Medpq)(py)2(NCS)2] and [Fe(Medpq)(py)2(NCSe)2] neutral species interact each other via π-stacking, resulting in a one-dimensional extended structure for both 1 and 2. There exist C–HX (X = S, Se) hydrogen bonds for both complexes. Variable-temperature magnetic susceptibility measurements and Mössbauer spectroscopy reveal the occurrence of a gradual spin transition. The transitions are centered at T1/2 = 120 K for 1 and T1/2 = 180 K for 2, respectively. 相似文献
11.
Claudia Graiff Andrea Ienco Chiara Massera Carlo Mealli Giovanni Predieri Antonio Tiripicchio Franco Ugozzoli 《Inorganica chimica acta》2002,330(1):95-102
The reaction between the linear trinuclear complex [Pt{Fe(CO)3(NO)}2(PhCN)2] and Ph2(2-C5H4N)PSe led to the isolation and characterization of the 46-electron cluster [(CO)3Fe(μ3-Se){Pt(CO)P(2-C5H4N)Ph2}2] (1), whose structure has been determined by X-ray diffraction methods. The cluster typology, which consists of an open triangle Pt---Fe---Pt capped by a μ3-Se atom, is rather rare. The chemical bonding in 1 and in similar systems has been analyzed through density functional theory (DFT) and qualitative MO approaches. A strict analogy with the well understood L2M(μ-acetylene)ML2 systems is invoked by considering 1 as formed by the (CO)3FeSe tetrahedral unit stabilized by sidewise interactions of the triple bond with two d10-L2M fragments. Otherwise, the 18-electron (CO)3FeSe monomer is unstable as an isolate molecule. This is confirmed by our DFT calculations that indicate how the well characterized dimer (CO)3Fe(μ-Se2)Fe(CO)3 lies as much as, approximately, 58 kcal mol−1 deeper in energy. Finally, by considering an analogy with [L2M(μ-dichalcogen)ML2]0, +2 redox systems (M=Pd, Pt), reduction of 1 to a dianion has been hypothesized and the structure of the latter has been tentatively explored by DFT calculations. 相似文献
12.
Ali Canlier 《Inorganica chimica acta》2010,363(1):1-4850
Crystal structure of [ReO2(4-MeOpy)4][PF6] (4-MeOpy = 4-methoxypyridine) complex has been examined by the single crystal X-ray analytical method. This complex shows a trans-dioxo geometry (average Re-O bond length = 1.766(2) Å) and its equatorial plane is occupied by four 4-MeOpy molecules (average Re-N bond length = 2.156(4) Å). Electrochemical reaction of [ReO2(4-MeOpy)4]+ in CH3CN solution containing tetra-n-butylammonium perchlorate as a supporting electrolyte has been studied using cyclic voltammetry at 24 °C. Cyclic voltammograms show one redox couple around 0.65 V (Epa) and 0.58 V (Epc) [versus ferrocene/ferrocenium ion redox couple, (Fc/Fc+)]. Potential differences between two peaks (ΔEp) at scan rates in the range from 0.01 to 0.10 V s−1 are 65 mV, which is almost consistent with the theoretical ΔEp value (59 mV) for the reversible one electron transfer reaction at 24 °C. The ratio of anodic peak currents to cathodic ones is 1.04 ± 0.03 and the (Epa + Epc)/2 value is constant, 0.613 ± 0.001 V versus Fc/Fc+, regardless of the scan rate. Spectroelectrochemical experiments have also been carried out by applying potentials from 0.40 to 0.77 V versus Fc/Fc+ with an optically transparent thin layer electrode. It was found that the UV-visible absorption spectra show clear isosbestic points at 228, 276, and 384 nm, and that the electron stoichiometry is evaluated as 1.03 from the Nernstian plot. These results indicate that the [ReO2(4-MeOpy)4]+ complex is oxidized reversibly to the [ReO2(4-MeOpy)4]2+ complex. Furthermore, it was clarified that the [ReO2(4-MeOpy)4]2+ in CH3CN has the characteristic absorption bands at 236, 278, 330, 478, and 543 nm and their molar absorption coefficients are 4.3 × 104, 4.5 × 103, 1.0 × 104, and 6.1 × 103 M−1 cm−1 (M = mol dm−3), respectively. 相似文献
13.
Di-μ-azido-bis[azido(2-aminopyridine)aquo]dicopper(II), [Cu(2-ampy)(N3)2(H2O)]2, was synthesized and characterized by X-ray crystallography. The crystals are triclinic, space group P, with a = 7.142(1), b = 7.812(1), c = 9.727(1) Å, a = 96.52(1), β = 95.52(1), γ = 113.47(1)°, and Z = 1. The structure was refined to RF = 0.030 for 1960 observed MoKα diffractometer data. The dimeric molecule, which possesses a crystallographic inversion center, contains both terminal and μ(1)-bridging azido groups. Each copper(II) atom is further coordinated by a 2-aminopyridine ligand (via its ring N atom) and a water molecule to give a distorted square pyramid, with the metal atom raised by 0.17 Å above the N4 basal plane [CuN (ring) = 2.001(2), CuN (azide) = 1.962(3)–2.018(2) Å] towards the apical aquo ligand [CuO = 2.371(2) Å]. Each water molecule forms an intramolecular O?HN (amine) acceptor hydrogen bond, and is linked by two OH?N (terminal azide) intermolecular donor hydrogen bonds to adjacent dimeric complexes to yield a layer structure parallel to (001). Infrared and electronic spectral data are presented and discussed. 相似文献
14.
[NBun4]2[W(C3Se5)3] (C3Se52− = 1,3-diselenole-2-selone-4,5- diselenolate(2−)) was prepared by the reaction of Na2[C3Se5] with WCl6 in ethanol, followed by addition of [NBun4]Br. The cyclic voltammogram in dichloromethane exhibits two oxidation peaks at −0.04 and +0.03 V (versus SCE). The complex reacted with [Fe(C5Me5)2][BF4], iodine or [TTF]3[BF4]2 (TTF·+ = the tetrathiafulvalenium radical cation) in acetonitrile to afford the oxidized complexes [Fe(C5Me5)2]0.5[W(C3Se5)3], [NBun4]0.1[W(C3Se5)3] and [TTF]0.5[W(C3Se5)3], respectively. Current-controlled electrochemical oxidation of the complex in acetonitrile gave [NBun4]0.6[W(C3Se5)3]. The oxidized complexes exhibit electrical conductivities of 4.7×10 −5−1.5×10−3 S cm−1 at room temperature measured for compacted pellets. Electronic absorption, IR and ESR spectra of these complexes are discussed. 相似文献
15.
The copper(II) complex of the acyclic EBTA ligand (H4EBTA = 1,2-bis(2-aminoethoxy)benzene-N,N,N′,N′-tetraacetic acid) has been prepared and characterized by X-ray analysis. The two copper ions of the dinuclear unit present the same distorted octahedral coordination polyhedra. The EBTA ligand is shared between two copper coordination centres, with the formation of centrosymmetric dimers, which are linked in a supramolecular tridimensional structure via additional interactions through the coordinated waters molecules with adjacent carboxylic oxygen atoms. The stability and protonation constants of EBTA with Cu(II) and Zn(II) ions indicate a higher stability of these complexes with respect to the corresponding complexes with the more flexible EGTA ligand (H4EGTA = ethyleneglycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid). On the other hand, the lower stability of [Gd(EBTA)]− than [Gd(EGTA)]− results in a decreased overall selectivity (lower Ksel) of EBTA towards Gd(III) and suggests that this complex may undergoes transmetallation reactions under physiological conditions. 相似文献
16.
Pavel Nesterenko Ilia Levitin Nina Chernoglazova Elena Paskonova Natalia Penner Marina Tsikalova 《Inorganica chimica acta》1998,280(1-2):295-301
The electrophoretic migration behavior of acid-sensitive cationic alkylcobalt(III) complexes with tridentate Schiff bases and amines as well as that of related ‘inorganic’ cobalt(III) chelates with tridentate and tetradentate Schiff bases was studied. A correlation of the electrophoretic mobility of the organocobalt complexes in question with their structure was established. An attempt to optimize the analytical procedures for capillary electrophoretic separation of these rather labile complex cations is outlined. Their decomposition in solutions under ambient conditions was surveyed using this technique. 相似文献
17.
The labile cations [Cu(F-BF3)(PCy3)2] and [Cu(OTf)(PCy3)2] are versatile precursors for the formation of [Cu(X)(PCy3)2] (X = Br, I, SCN, N3) complexes by metathesis with NaX. The azide [Cu(N3)(PCy3)2] is triclinic, space group
, a = 9.755(4), B = 22.78(1), C = 9.284(6) Å, = 96.76(3), β = 115.36(3), γ = 94.20(5)°, Z = 2. 相似文献
18.
Complexes of the type [Pt(amine)4]I2 were synthesized and characterized mainly by multinuclear (195Pt, 1H and 13C) magnetic resonance spectroscopy. The compounds were prepared with different primary amines, but not with bulky amines, due to steric hindrance. In 195Pt NMR, the signals were observed between −2715 and −2769 ppm in D2O. The coupling constant 3J(195Pt-1H) for the MeNH2 complex is 42 Hz. In 13C NMR, the average values of the coupling constants 2J(195Pt-13C) and 3J(195Pt-13C) are 18 and 30 Hz, respectively. The crystal structure of [Pt(EtNH2)4]I2 was determined by X-ray diffraction methods. The Pt atom is located on an inversion center. The structure is stabilized by H-bonding between the amines and the iodide ions. The compound with n-BuNH2 was found by crystallographic methods to be [Pt(n-BuNH2)4]2I3(n-BuNHCOO). The crystal contains two independent [Pt(CH3NH2)4]2+ cations, three iodide ions and a carbamate ion formed from the reaction of butylamine with CO2 from the air. When the compound [Pt(CH3NH2)4]I2 was dissolved in acetone, crystals identified as trans-[Pt(CH3NH2)2(H3CNC(CH3)2)2]I2 were isolated and characterized by crystallographic methods. Two trans bonded MeNH2 ligands had reacted with acetone to produce the two N-bonded Schiff base Pt(II) compound. 相似文献
19.
A new complex of composition [Cu(2-NO2bz)2(nia)2(H2O)2] (1) (nia = nicotinamide, 2-NO2bz = 2-nitrobenzoate) has been prepared and its composition and stereochemistry as well as coordination mode have been determined by elemental analysis, electronic, infrared and EPR spectroscopy, magnetization measurements over the temperature range 1.8-300 K, and its structure has been solved, as well. The complex structure consists of the centrosymmetric molecules with Cu(II) atom monodentately coordinated by the pair of 2-nitrobenzoato anions and by the pair of nicotinamide molecules, forming nearly tetragonal basal plane, and by a pair of water molecules that complete tetragonal-bipyramidal coordination polyhedron about the copper atom. The complex 1 exhibits magnetic moment μeff = 1.86 B.M. at 300 K which decreases to μeff = 1.83 B.M. at 1.8 K. The magnetic susceptibility temperature dependence obeys Curie-Weiss law with Curie constant of 0.442 cm3 K mol−1 and with Weiss constant of −1.0 K. EPR spectra at room temperature as well as at 77 K are of axial type with g⊥ = 2.065 and g∥ = 2.280 and exhibit clearly, but partially resolved parallel hyperfine splitting with AII = 160 G, that is consistent with the determined molecular structure of 1. In order to analyze the factors influencing the degree of tetragonal distortion of coordination polyhedron, the dataset of 72 structures similar to that of 1 was extracted from CCD and analyzed. A significant correlation between the average Cu-Oax bond length and tetragonality parameter τ which was found as a consequence of the Jahn-Teller effect. 相似文献
20.
Reaction of [Ru2(O2CMe)4]Cl with K3[Cr(CN)5NO] in water forms Hx[RuII/III2(O2CMe)4]3−x-[Cr(CN)5NO]·zH2O (x = 0.2) that magnetically orders at 4.0 K and possesses an interpenetrating body centered cubic [a = 13.2509(2) Å] structure with random locations of the bridging nitrosyl ligands, and x/3 vacant cation sites. Similarly, the aqueous reaction of [Ru2(O2CMe)4]Cl with Na2[Fe(CN)5NO] forms paramagnetic [Ru2(O2CMe)4]2[Fe(CN)5NO]·H2O, which has a similar tetragonal interpenetrating structure [a = 13.0186(1) Å, c = 13.0699(2) Å] where the NO ligands are presumably nonbridging and 1/3 of the expected cation sites are unoccupied. The presence of uncoordinated NO sites in addition to missing neighboring [Ru2(O2CMe)4]+ units, results in significant vacancies (or holes) in the lattice. 相似文献