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1.
The reaction of cis- or trans-[Ru(CNtBu)4(CN)2] with Fe(III) compounds leads to the formation of molecular squares of the general formula cyc-[Ru(CN-tBu)4(CN)2FeX3]2 or one-dimensional coordination polymers [Ru(CN-tBu)4(CN)2FeX3]n, respectively. Temperature dependent susceptibility measurements indicate that the magnetic properties of the coordination compounds are determined by their molecular structure. Of particular importance is the local symmetry at the iron(III) center which is related to the coordinating anion. The magnetic properties are best described in terms of weak antiferromagnetic interactions between the iron centers for the molecular squares as well as the coordination polymer with X = NO3 and as weak ferromagnetic interactions in case of the linear coordination polymer with X = Cl. For all compounds zero field splitting at low temperatures has to be taken into account.  相似文献   

2.
New oxovanadium(V) complexes with internally functionalized oximes of the type VO{OPri}3−n{ONC(CH3)(Ar)}n] (where Ar = C4H3O-2, C4H3S-2 and C5H4N-2 and n = 1-3) have been prepared in quantitative yields by the reaction of VO(OPri)3 with the corresponding oximes in various stoichiometric ratios in refluxing anhydrous benzene. The products have been characterized by elemental analyses and spectroscopic (FT IR, 1H, 13C{1H} and 51V NMR) studies. FAB mass spectral analysis of [VO{OPri}{ONC(CH3)C4H3S}2] indicates the monomeric nature of the complex. 51V NMR values for these complexes suggest the formation of tetra-coordinate species in solution. However, the single crystal X-ray diffraction studies of [VO{ONC(CH3)(C4H3O-2)}3] and [VO{ONC(CH3)(C4H3S-2)}3] · 0.5C6H6 exhibit the presence of vanadium(V) atoms in a unique hepta-coordination state with distorted pentagonal bipyramidal geometry in the solid state. The oxo- atom occupies the axial position while the oximato ligands are bonded in a dihapto (η2-N,O) manner with the formation of three membered rings.  相似文献   

3.
Reaction of Mo(CO)4(NCCH3)2 and 7-aza-2-tosylnorbornadiene (7-azaNBD) yielded five air-stable Mo complexes. One is Mo(CO)44-7-azaNBD), in which the molybdenum atom is chelated by the two π-bonds of 7-azaNBD. The other four are isomers of Mo(CO)22-7-azaNBD)2, in which the molybdenum atoms are chelated by the nitrogen atom and one of the two double bonds of 7-azaNBD. In one pair of the isomers, the metal binds to C(2)C(3) of both 7-azaNBD ligands; whereas in the other pair of isomers the metal binds to C(2)C(3) of one 7-azaNBD ligand and C(5)C(6) of another ligand. All structures were fully characterized by NMR spectra. A single crystal of compound 4 was analyzed by X-ray diffraction analysis, which was found to be monoclinic with a = 8.4199, b = 23.984, c = 16.395 Å, and β = 99.99°.  相似文献   

4.
In this paper it is reported the synthesis of the phosphonium salts [Ph2P(CH2)n(Ph)2PCH2COOMe]Br (n = 1 (1), 2 (2)) and [Ph2P(CH2COOMe)(CH2)n(Ph)2PCH2COOMe]Br2 (n = 3 (3)) derived from the reactions of the diphosphines dppm, dppe and dppp with methyl bromoacetate. By reaction of the monophosphonium salt of dppm and dppe with the strong base Na[N(SiMe3)2] the corresponding carbonyl stabilized ylides Ph2P(CH2)n(Ph)2PCHCOOMe (n = 1 (4), 2 (5)) were obtained. The Ph2P(CH2)2(Ph)2PCHCOOMe (5) ylide was reacted with Pd(II) and Pt(II) substrates. From these reactions were isolated exclusively complexes in which the ylide was chelated to the metal through the free phosphine group and the ylidic carbon atom. A further reaction of the Ph2P(CH2)2(Ph)2PCHCOOMe (5) ylide with 1.5 equiv. of Na[N(SiMe3)2] gives the bifunctionalized ketenylidene Ph2P(CH2)2(Ph)2PCCO (6) system. This cumulenic ylide reacts with Pt(II) complexes to form a chelated derivative in which IR and NMR spectra suggest the breaking of the CC bond of the -CCO group.  相似文献   

5.
Bimetallic alkylidene complexes of molybdenum (RF3O)2(ArN)MoCH-SiMe2-CHMo(NAr)(ORF3)2 (1) and (RF3O)2(ArN)MoCH-SiPhVin-CHMo(NAr)(ORF3)2 (2) (Ar = 2,6-C6H3; RF3 = CMe2CF3) have been prepared by the reactions of vinyl silicon reagents Me2Si(CHCH2)2 and PhSi(CHCH2)3 with known alkylidene compound PhMe2C-CHMo(NAr)(ORF3)2. Complexes 1 and 2 were structurally characterized. Ring opening metathesis polymerization (ROMP) of cyclooctene using compounds 1 and 2 as initiators led to the formation of high molecular weight polyoctenamers with predominant trans-units content in the case of 1 and predominant cis-units content in the case of 2.  相似文献   

6.
Reaction of [Ru2(O2CMe)4]Cl and K2[Ni(CN)4] forms [Ru2(O2CMe)4]2[Ni(CN)4] with the targeted layered structure possessing Ru-NCNi linkages, albeit strained, with Ru-NC and Ni-CN angles in the range of 147-167°. The magnetic properties of [Ru2(O2CMe)4]2[Ni(CN)4] can be fit to a zero-field splitting model with D/kB = 95 K (66 cm−1).  相似文献   

7.
Treatment of the 16-electron hydroxy hydride complex [Ru(IMes)2(CO)H(OH)] (1, IMes = 1,3-bis-(2,4,6-trimethylphenyl)imidazol-2-ylidene) with HCCR affords the alkynyl species [Ru(IMes)2(CO)H(CCR)] (R = Ph 3, SiMe3, 4) and [Ru(IMes)2(CO)(CCR)2] (R = Ph, 5). Deuterium labelling studies show that the mono-alkynyl complexes are formed via hydrogen transfer from a coordinated alkyne ligand to Ru-OH, while bis-alkynyl formation is proposed to take place through hydrogen transfer to Ru-H. Both 3 and 5 readily coordinate CO to give the corresponding dicarbonyl species 6 and 7. Addition of HCCPh to the hydride chloride precursor [Ru(IMes)2(CO)HCl] (2) results in a different reaction pathway involving alkyne insertion into the Ru-H bond to yield the alkenyl chloride complex [Ru(IMes)2(CO)(CHCHPh)Cl] 8. Complexes 3-8 have been structurally characterised by X-ray crystallography.  相似文献   

8.
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   

9.
Novel bipyridine-type linking ligands L1 ((4-py)-CHN-C10H6-NCH-(4-py)) and L2 ((3-py)-CHN-C10H6-NCH-(3-py)), a pair of isomers due to possessing different pairs of terminal pyridyl groups, were prepared by the Schiff-base condensation. In ligand L1, the N?N separation between the terminal pyridyl groups is 16.0 Å, with their nitrogen donor atoms at the para positions (4,4′). The corresponding N?N separation in ligand L2 is 14.2 Å, with the nitrogen donor atoms at the meta positions (3,3′). 1-D zigzag-chain coordination polymers [Zn(L1)(NO3)2] (1) and [Zn(L2)(NO3)2] (2) were prepared by reactions of Zn(NO3)2 · 6H2O with ligands L1 and L2, respectively, by solution diffusion. Polymer 3, [Cd(L1)1.5(NO3)2], prepared from Cd(NO3)2 · 4H2O and L1, exhibits a 1-D ladder structure, whose repeating ladder unit consists of four Cd metals and four L1 ligands to create a large 76-membered ring with dimensions of 20.8 × 20.8 Å. All products were structurally characterized by X-ray diffraction.  相似文献   

10.
The reaction of the chelating P,N ligand RNC(But)CH(R)PPh2 (R = SiMe3) (1) with CuCl and CuCl2 (probably by way of reduction to Cu(I) by the phosphine ligand) or Cu(NCCH3)4ClO4 yielded the dimeric 1:1 complex [Cu{PPh2CH(R)C(But)NR}Cl]2 (2) or the monomeric 2:1 complex [Cu{PPh2CH(R)C(But)NR}2]ClO4 (3), respectively. The presence of trace amounts of water during the reaction resulted in the successive cleavage of the two trimethylsilyl groups of the ligand and the formation of the monomeric chelate complexes [Cu{PPh2CH(R)C(But)NH}2]ClO4 (4) and [Cu{PPh2CH2C(But)NH}2]ClO4 (5). Oxidation of 5 by atmospheric oxygen led to small quantities of the blue Cu(II) complex [Cu{(O)PPh2CH2C(But)NH}2](ClO4)2 (6). The dimeric gold complexes [Au{PPh2CH2C(But)NH}]2X2 (X = BF4, ClO4) (7) were similarly obtained from the previously described Au{PPh2CH(R)C(But)NR}Cl by replacing the covalently bound chlorine with the weakly coordinating anions in the presence of small quantities of water. The solution and solid state structures (except 5) of all complexes were determined by NMR spectroscopy and X-ray crystallography.  相似文献   

11.
The reaction of 2 equiv. of [Os3(CO)10(MeCN)2] with R-CC-L-CC-R (R = H, L = (C4H2S); R = SiMe3, L = (C4H2S-C4H2S), (C4H2S-C4H2S-C4H2S), (C4H2S)-(C14H8)-(C4H2S)) affords the series of linked clusters [{Os3(CO)10}(HCC(C4H2S)CCH){Os3(CO)10}] (1), [{Os3(CO)10}(Me3SiCC(C4H2S-C4H2S)CCSiMe3){Os3(CO)10}] (2), [{Os3(CO)10}(Me3SiCC(C4H2S-C4H2S-C4H2S)CCSiMe3){Os3(CO)10}] (4) and [{Os3(CO)10}(Me3SiCC(C4H2S)-(C14H8)-(C4H2S)CCSiMe3){Os3(CO)10}] (6) as the major products. The complexes have been characterised by a range of spectroscopic methods and, in the case of 1 and 2 by single crystal X-ray crystallography. The alkyne groups cap the osmium triangles in the expected μ32-||-bonding mode and each triangle is coordinated by nine terminal and one μ2-carbonyl group. Solution UV-Vis spectra of the complexes were similar to those observed for the free ligands consistent with there being little delocalisation between the cluster units and the thiophene groups.  相似文献   

12.
Infrared and Raman spectra of solid trans-dichloro-bis[diperfluoroethyl(phenyl)phosphine]platinum(II), trans-Pt[PPh(CF3CF2)2]2Cl2, have been studied at high external pressures up to ∼50 kbar with the aid of a diamond-anvil cell. A gradual, pressure-induced phase transition, most probably second order, was observed in the 21-34 kbar pressure range. In the IR spectra, the bands assigned to the CF stretching modes of the CF3 groups exhibit larger pressure sensitivities than do those associated with the CF stretching modes of the CF2 groups, most probably because of their physical location on the outside in the molecules in the unit cell. The fairly high pressure sensitivities of the symmetric PtCl stretching mode in both the low and high pressure phases (0.46 and 37 cm−1/kbar, respectively) are considered to reflect the low force constant associated with the long PtCl bond length thus making this vibration more susceptible to compression.  相似文献   

13.
The electrospray mass spectrum (ESI-MS) of cis-[Ru(NO)Cl(bpy)2]Cl2 (bpy=2,2-bipyridine), obtained from 50% CH3OH/50% H2O as the mobile solvent, exhibited ruthenium-containing ions derived from a {[RuII(NO+)Cl(bpy)2]2+, Cl}+ ion pair (m/z=514) and [RuII(NO+)Cl(bpy)2]2+ (m/z=239.5). [RuIIICl(bpy)2]2+, from the loss of NO from the 239.5 ion, is detected at m/z=224.5. Only the m/z 514 ion pair is detected when 100% CH3OH mobile solvent is used, but the presence of even small amounts of water prompted the additional detection of the m/z 239.5 and m/z 224.5 ions under tandem MS-MS conditions. Ruthenium-chloro-containing ions appear as a characteristic collection of eight main, and four lesser, intense ions created from combinations 104Ru, 102Ru, 101Ru, 99Ru, 98Ru, 96Ru, 35Cl and 37Cl isotopes with minor contributions from 13C, etc. For convenience of discussion, only the most abundant m/z species are mentioned herein as representative of all the isotopically distributed ions.Four fragmentation channels are detectable from the m/z=514 chloride ion pair: (1) the loss of HCl (main channel; ca. 50% of fragmentation events), (2) the loss of NO (ca. 12% ), (3) the loss of bpy (minor pathway), and (4) the loss of Cl atom (ca. 38% ).Loss of NO from ion m/z 514 yields ion m/z 484, which is the precursor of ions m/z 448 (by loss of HCl), m/z 328 (by loss of bpy) and m/z 292 (by loss of HCl and bpy). Loss of HCl from ion m/z 514 generates ion m/z 478, [RuII(NO+)Cl(bpyH)(bpy-H)]+, deprotonated at the ortho C-H of one bpy ligand. In MS-MS experiments, the m/z 478 ion was established to undergo loss of NO, producing ion m/z 448, rejoining further fragmentation process for ion m/z 448 at this point. Loss of neutral bipyridine from m/z 514 in low yield produces ion m/z 358, which undergoes further loss of NO to form [RuCl2(bpy)]+ ion (m/z=328). MS-MS “neutral loss of 30” spectra confirmed the NO loss events as part of the fragmentation sequence for all four pathways.A fourth species of m/z=479 from the “514” ion is obtained by an internal electron transfer from Cl of the ion pair, and loss of the resultant neutral Cl atom. The product [RuII(NO·)Cl(bpy)2]+ “479” fragment undergoes facile loss of NO to generate [RuIICl(bpy)2]+ (m/z=449). Ion m/z 449 gives rise to ions m/z 413 (loss of HCl) and m/z 257(loss of HCl and bpy). MS-MS experiments confirm the neutral loss of Cl from the m/z 514 ion, and the formation of the m/z 449 ion via m/z 479 and m/z 514 parents. This pathway was not observed in a prior study for the related complex, [Ru(NO)Cl(dpaH)(dpa)]+ (dpaH=2,2-dipyridylamine), which does not have an external Cl in an ion pair.  相似文献   

14.
[PPN][Se5Fe(NO)2] (1) and [K-18-crown-6-ether][S5Fe(NO)2] (2′) were synthesized and characterized by IR, UV-Vis, EPR spectroscopy, magnetic susceptibility, and X-ray structure. [PPN][Se5Fe(NO)2] easily undergoes ligand exchange with S8 and (RS)2 (R = C7H4SN (5), o-C6H4NHCOCH3 (6), C4H3S (7)) to form [PPN][S5Fe(NO)2] and [PPN][(SR)2Fe(NO)2]. The reaction displays that [E5Fe(NO)2] (E = Se (3), S (4)) facilely converts to [Fe4E3(NO)7] by adding acid HBF4 or oxidant [Cp2Fe][BF4] in THF, respectively. Obviously, complexes 1 and 2′ serve as the precursors of the Roussin’s black salts 3 and 4. The electronic structure of {Fe(NO)2}9 core of [Se5Fe(NO)2] is best described as a dynamic resonance hybrid of {Fe+1(NO)2}9 and {Fe−1(NO+)2}9 modulated by the coordinated ligands. The findings, EPR signal of g = 2.064 for 1 at 298 K, implicate that the low-molecular-weight DNICs and protein-bound DNICs may not exist with selenocysteine residues of proteins as ligands, since the existence of protein-bound DNICs and low-molecular-weight DNICs in vitro has been characterized with a characteristic EPR signal at g = 2.03. In addition, complex 2′ treated human erythroleukemia K562 cancer cells exposed to UV-A light greatly decreased the percentage survival of the cell cultures.  相似文献   

15.
A seven-coordinate FeIII complex, [Fe(oda)(H2O)2(NO3)], was obtained after dissolving Fe(NO3)3 · 9H2O in an aqueous solution of oxydiacetic acid (H2oda) at room temperature. In the solid state, the FeIII center adopts a pentagonal bipyramid geometry with an {FeO7} core formed by a tridentate oda2− and a bidentate in the equatorial plane, and two axial water molecules. Magnetic measurements and EPR spectra revealed the presence of S = 5/2 FeIII centers with rhombic zero field splitting parameters (D = 0.81 cm−1, E/D = 0.33 ). Weak antiferromagnetic interactions with J ≈ −0.06 cm−1 operating between neighboring Fe ions connected through Fe-O-C-O?H-O-Fe paths are estimated using the molecular field approximation.  相似文献   

16.
Amination of acetonitrile by the amines MeNH2, PrnNH2, PriNH2, ButNH2, and Et2NH is efficiently promoted by the lanthanide iodides LnI2 (Ln = Nd, Dy, Tm), LnI3 (Ln = Pr, Nd, Dy) and LnI3(THF)3 (Ln = Pr, Nd, Dy). The formed mono- and N,N′-disubstituted amidines MeC(NH)NHR (R = Pri, But), MeC(NH)NEt2, MeC(NR)NHR (R = Me, Prn) were isolated mainly as the complexes with starting iodide of general composition LnI2(amidine)x (1) or LnI3(amidine)x (2) (x = 3-8). In the products 1, which evidently are the mixtures of LnI2+, and LnI3 derivatives, the metal exists in trivalent state but one of the ligands actually is amidinate anion. A part of the generated amidines remains in the reaction solutions in free form. Heating of the 1 and 2 in vacuum at 150-200 °C affords corresponding amidine and the complexes with reduced amount of the amidine ligands LnI2(amidine)y (3) or LnI3(amidine)y (4) (y = 2-3). The products 3 and 4 displayed the same catalytic activity in the acetonitrile-amine cross-coupling as the initial iodides. SmI2 and especially YbI2 revealed lower activity. The structure of isopropylacetamidine (5), tert-butylacetamidine (6) and {Dy[MeC(NH)NEt2]6}I3(MeCN) (7) were determined by X-ray diffraction analysis.  相似文献   

17.
The synthesis and characterisation of [Pt{4′-(Np1)-trpy}(CCPh)]SbF6 (1) and [Pt{4′-(Np1)-trpy}{CC(CH2)2CH3}]SbF6 (2) [4′-(Np1)-trpy = 4′-(1-naphthyl)-2,2:6′,2′-terpyridine] are described. Complexes 1 and 2 exhibit unimolecular 3MLCT (MLCT = metal-to-ligand charge transfer) emission in acetonitrile and in a low concentration 77 K glass solution in butyronitrile. The high concentration glass emission as well as the emission in the solid state is from a 3MMLCT (MMLCT, metal-metal-to-ligand charge transfer) excited state, reflecting the presence of interactions in these media.  相似文献   

18.
The reaction of neodymium diiodide NdI2 (1) with acetonitrile is accompanied by C-C coupling and formation of bis(ethylimine)ethylamine/acetonitrile complexes {[(MeCNH)2CMeNH2]NdI(MeCN)5}I2 (2) and {[(MeCNH)2CMeNH2]Nd(MeCN)6}I3 (3). Yields of the products are 9% and 50%, respectively. Probable scheme of the complexes formation is discussed. Treatment of 3 with 2 equiv. of 1 in THF affords NdI3(THF)3, hydrogen and monoiodide complex containing presumably bis(imide)amine ligand, NdI[(MeCN)2CMeNH2]. The X-ray analysis revealed that in the molecule of 2 one I anion is directly bonded to Nd3+ cation while two other Ianions are not in contact to the metal centre. The molecule of 3 is isostructural to previously obtained Dy and Tm analogues. All three I anions in it are located away from Nd3+ cation.  相似文献   

19.
Syntheses and spectroscopic features (IR, NMR and ESI MS) are reported for five 1:2 adducts of CuX with dppe (X = I, ClO4, NCS, O3SCF3 (tfs) BH4; dppe = Ph2P(CH2)2PPh2). ESI MS and 31P NMR spectroscopy indicate that these species dissociate in solution yielding free diphosphine and 3:2 species. A single crystal X-ray structure determination has been carried out on Cu(dppe)2NCS defining a four-coordinate complex of the form [(P,P′-dpex)M(P-dpex)X] for M = Cu, the thiocyanate being N-bound; the ionic [Cu(P,P′-dppe)2]tfs has also been structurally characterized.  相似文献   

20.
The molecular structure of copper(II) chloride complex with acrylamide (AAmCH2CHCONH2), [Cu(AAm)4Cl2], was determined using X-ray diffraction analysis. The complex crystallizes in the cubic space group I-43d with a = 17. 8310(2) Å, β = 90°, and V = 5669.27(11) Å3 for Z = 12. The acrylamide molecules bind to the metal center via the carbonyl oxygen atom (Cu-O 1.996 Å). The coordination geometry of the metal center in the complex involves a tetragonally distorted octahedral structure with four O-donor atoms of acrylamide bonded in the equatorial positions and two chlorides in the apical positions. Comparison of crystal structure data of acrylamide and metal acrylamide complexes of those formed with divalent transition metal chlorides has been summarized.  相似文献   

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