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1.
Perfluorophenanthrene and decamethylferrocene cocrystallize as a molecular adduct in monoclinic space group P21/c with a = 8.842(2), b = 11.262(1), c = 30.695(8) Å, β = 95.89(2)°, V = 3040.3(8) Å3, Z = 4. The structure was refined to R = 0.0537 for 1567 observed reflections. The perfluoroarene is twisted and chiral; the crystal is a racemate, however.  相似文献   

2.
The synthesis and characterization of a ferrocenyl-derived tridentate ligand, ferrocenyltris((methylthio)methyl)borate (FcTtP), and its representative metal complexes, [(FcTt)Cu]4 and [FcTt]2M (M = Fe, Co and Ni), are reported. The M = Fe complex exhibits spin-crossover behavior with a μeff = 1.19 μB at 25°C. The low-spin Co(II) derivative (1.88 μB) exhibits a characteristic axial electron paramagnetic resonance (EPR) spectrum, gav = 2.13, A = 53 G and A¦ = 43 G. The [FcTt]2M complexes display reversible two-electron redox processes assigned to ligand-centered events about 200 mV negative of the ferrocene-ferrocenium couple. [(FcTt)Cu]4 and [FcTt]2Ni have been characterized by X-ray diffraction. X-ray data for [(FcTt)Cu]4: monoclinic space group C2/c, with a = 24.3747(3) Å, b = 20.0857(2) Å, c = 17.2747(4) Å, β = 95.843(1)°, V = 8413.5(3) Å3, and Z = 4; [FcTt]2Ni: monoclinic space group C2/c, with a = 12.6220(3) Å, b = 11.6002(3) Å, c = 25.0125(7) Å, β = 94.067(1)°, V = 3653.1(2) Å3, and Z = 4.  相似文献   

3.
The thermal and photochemical reactions of CpRe(PPh3)2H4 and CpRe(PPh3)H4 (Cp = η5-C5H5) with PMe3, P(p-tolyl)3, PMe2Ph, DMPE, DPPE, DPPM, CO, 2,6-xylylisocyanide and ethylene have been examined. While CpRe(PPh3)2H2 is thermally inert, it will undergo photochemical substitution of one or two PPh3 ligands. With ethylene, substitution is followed by insertion of the olefin into the C-H bond of benzene, giving ethylbenzene. CpRe(PPh3)H4 undergoes thermal loss of PPh3, which leads to substituted products of the type CpRe(L) H4. Photochemically, reductive elimination of dihydrogen occurs preferentially. The complex trans-CpRe(DMPE)H2 was structurally characterized, crystallizing in the monoclinic space group P21/n (No. 14) with a = 6.249(6), b = 16.671(8), c = 13.867(7) Å, β = 92.11(6)°, V = 1443.7(2.9) Å and Z = 4. The complex trans-CpRe(PMe2Ph)2H2 was structurally characterized, crystallizing in the monoclinic space group P21/n (No. 14) with a = 7.467(3), b = 23.874(14), c = 11.798(6) Å, β = 100.16(4)°, V = 2070.2(3.4) Å3 and Z = 4.  相似文献   

4.
Unsymmetrical di(phosphine) ligands (dpp)2Rop (1a, b = bis(diphenylphosphino)-2-alkyl-3-oxapropane (alkyl = methyl and ethyl)) and (dpp)2oCy (1c = trans-2-diphenylphosphinocyclohexyl diphenylphosphinite) and their Pt(II) dichloride complexes, PtCl2((dpp)2mop) (2a), PtCl2((dpp)2eop) (2b) and PtCl2((dpp)2oCy) (2c), have been synthesized and characterized by NMR spectroscopy. The crystal structures of 2b and 2c show that the geometry about the platinum centers is square planar. In 2b, the metal and di(phosphine) ligand chelate ring are in a chair conformation, whereas in 2c, the chelate ring conformation is a skewed boat. Initial reaction of sodium borohydride with 2a, b, c yields the monohydride monochloride complexes PtHCl((dpp)2mop) (5a), PtHCl((dpp)2eop) (5b) and PtHCl((dpp)2oCy) (5c). At longer reaction times, fluxional dimeric species are obtained, [PtH((dpp)2mop)]2 (4a), [PtH((dpp)2eop)]2 (4b) and [PtH((dpp)2oCy)]2 (4c),and in the case of 4c two different isomers exist. The dihydride complexes PtH2((dpp)2mop) (3a), PtH2((dpp)2eop) (3b) and PtH2((dpp)2oCy) (3c), are prepared by further reaction of NaBH4 and 2. Hydrogen cycling is facile in the dihydride complexes 3a, b, c, and oxidative addition of H2 proceeds in a pairwise manner as determined by the observation of parahydrogen induced polarization (PHIP) in the 1H NMR spectra. The reductive elimination of H2 is also shown to be concerted by reaction of dihydride complexes with D2. Crystal data: 2b (C30H32Cl6OP2Pt), monoclinic, space group P21/c (No. 14), a = 13.7040(1), b = 11.3430(7), c = 21.3880(9) Å, β = 97.923(9)°, V = 3292.9(2) Å3 and Z = 4; 2c (C30H30Cl2OP2Pt), monoclinic, space group P21 (No. 4), a = 11.7360(2), b = 8.4311(2), c = 14.2789(2) Å, β = 101.290(1)°, V = 1385.52(4) Å3 and Z = 2.  相似文献   

5.
The N,N-diethylcarbamato derivative of zirconium(IV), Zr(O2CNEt2)4 has been studied by X-ray crystallography. Crystal data: C20H40Na4O8Zr, monoclinic, space group C2/c, a = 14.057(1), b = 12.168(1), c = 16.746(2) Å, β = 108.071(4)°, Z = 4, Dc = 1.356, F(000) = 1168, T = 213 K. The compound is isotypic with the corresponding niobium(IV) derivative with a dodecahedral coordination at the zirconium atom. By reaction of NbCl4(THF)2 with Tl(hfacac), the hexafluoroacetylacetonato derivative of niobium (IV), Nb(hfacac)4, has been prepared and structurally characterized. The compound crystallizes in the orthorhombic space group Pna21 with the following cell constants: a = 10.399(4), b = 15.852(9), c = 119.073(1) Å. It is not isotypic with the corresponding zirconium(IV) derivative, Zr(hfacac)4. Crystal data: C20H4F24O8Zr, monoclinic, space group P21/n, a = 11.974(4), b = 20.451(6), c = 13.140(3) Å, β = 104.487(11)°, Z = 4, Dc = 1.960, F(000) = 1776, T = 223 K. Although in both compounds the central metal atom shows a square antiprismatic coordination, the coordination mode of the ligands is different and slight deviations from the D4(llll) and C2(llss) ideal geometries have been observed in the case of niobium and zirconium, respectively. An EPR study has been performed on the Nb(IV) derivatives as diluted solid solutions in frozen organic solvents or in the diamagnetic matrix of the corresponding zirconium(IV) compound. The EPR spectra have confirmed the presence of non-interacting paramagnets in the solid solutions and, in the case of Nb(O2CNEt2)4, the point symmetry of the paramagnetic centre has been found to be in agreement with the results of the X-ray investigation. An EPR spectrum of rhombic symmetry has been observed for the hexafluoroacetylacetonato derivative of Nb(IV) when diluted in frozen THF solution or in Zr(hfacac)4.  相似文献   

6.
The complex [Et4N][W(CO)5OMe] (1) has been prepared from the reaction of the photochemically generated W(CO)5THF adduct and [Et4N][OH] in methanol. Complex 1 was shown to undergo rapid CO dissociation in THF to quantitatively provide the dimeric dianion, [W(CO)4OMe]22−. The resulting THF insoluble salt [Et4N]2[W(CO)4OMe]2 (2) has been structurally characterized by X-ray crystallography, with the doubly bridging methoxide ligands being in an anti configuration. Complex 2 was found to subsequently react with excess methoxide ligand in a THF slurry to afford the face-sharing octahedron complex [Et4N]3[W2(CO)6(OMe)3] (3) which contains three doubly bridging methoxide groups. In the absence of excess methoxide ligand complex 2 cleanly yields the tetrameric complex [Et4N]4[W(CO)3OMe]4 (4) which has been structurally characterized as a cubane-like arrangement with triply bridging μ3-methoxide groups and W(CO)3 units. Although complex 3 was not characterized in the solid state, the closely related glycolate derivative [Et4N]3[W2(CO)6(OCH2CH2OH)3] (5) was synthesized and its structure determined by X-ray crystallography. The trianions of complex 5 are linked in the crystal lattice by strong intermolecular hydrogen bonds. Crystal data for 2: space group P21/n, a = 7.696(2), b = 22.019(4), c = 9.714(2) Å, β = 92.22(3)°, Z = 4, R = 6.43%. Crystal data for 4: space group Fddd, a = 12.433(9), b = 24.01(2), c = 39.29(3) Å, Z = 8, R = 8.13%. Crystal data for 5: space group P212121, a = 11.43(2), b = 12.91(1), c = 29.85(6) Å, Z = 8, R = 8.29%. Finally, the rate of CO ligand dissociation in the closely related aryloxide derivatives [Et4N][W(CO)5OR] (R = C6H5 and 3,5-F2C6H3) were measured to be 2.15 × 10−2 and 1.31 × 10−3 s−1, respectively, in THF solution at 5°C. Hence, the value of the rate constant of 2.15 × 10−2 s−1 establishes a lower limit for the first-order rate constant for CO loss in the W(CO)5OMe anion, since the methoxide ligand is a better π-donating group than phenoxide.  相似文献   

7.
The syntheses of nitrosyl–dimethylsulfoxide–ruthenium(II) complexes with general formula mer-[RuCl3(L)(DMSO)(NO)] (L=DMSO or CD3CN) is reported. The mer-[RuCl3(DMSO)2(NO)] (1) complex was obtained from the reaction of [RuCl3(NO)] with the sulfoxide ligand in acetone. The mer-[RuCl3(CD3CN)(DMSO)(NO)] (2) compound was obtained from mer-[RuCl3(DMSO)2(NO)] maintained in deuterated acetonitrile. These data suggest a slow kinetic reaction due the low lability of the DMSO ligand coordinated to the {RuII–NO+} species. The crystal and molecular structures of (1) and (2) have been determined from X-ray studies. Crystal data: for (1), monoclinic, P21/c, a=8.8340(2) Å, b=12.0230(3) Å, c=13.7064(4) Å, β=114.546(2)°, Z=4, R1=0.0429; for (2), monoclinic, P21/n, a=10.0180(7) Å, b=9.5070(7) Å, c=13.3340(9) Å, β=102.264(4)°, Z=4, R1=0.0472. The spectroscopic characterization of (1), in solid state (infrared spectrum) and in solution (nuclear magnetic resonance and cyclic voltammetry) is also described.  相似文献   

8.
The metal ion complexing properties of the ligand HQC (8-hydroxyquinoline-2-carboxylic acid) are reported. The structures of [Zn(HQCH)2] · 3H2O (1) and [Cd(HQCH)2] · 3H2O (2) were determined (HQCH = HQC with phenol protonated). Both 1 and 2 are triclinic, space group , with Z = 2. For 1 a = 7.152(3), b = 9.227(4), c = 15.629(7) Å,  = 103.978(7)°, β = 94.896(7)°, γ = 108.033(8)°, R = 0.0499. For 2 a = 7.0897(5), b = 9.1674(7), c = 16.0672(11) Å,  = 105.0240(10)°, β = 93.9910(10)°, γ = 107.1270(10)°, R = 0.0330. In 1 the Zn has a distorted octahedral coordination geometry, with Zn–N of 2.00 and 2.15 Å, and Zn–O to the protonated phenolic oxygens of 2.431 and 2.220 Å. The structure of 2 is similar, with Cd–N bonds of 2.220 and 2.228 Å, with Cd–O bonds to the protonated phenolate oxygens of 2.334 and 2.463 Å. The structures of 1 and 2, and isomorphous Ni(II) and Co(II) HQC complexes reported in the literature, show very interesting short (<2.5 Å) O–O distances in H-bonds involving the protons on the coordinated phenolates and lattice water molecules. These are discussed in relation to the possible role of short low-energy H-bonds in alcohol dehydrogenase in mediating the transfer of the hydroxyl proton of the alcohol to an adjacent serine oxygen.

The formation constants for HQC are determined by UV–Visible spectroscopy at 25 °C in 0.1 M NaClO4 with Mg(II), Ca(II), Sr(II), Ba(II), La(III), Gd(III), Zn(II), Cd(II), Ni(II), Cu(II), and Pb(II). These show greatest stabilization with metal ions with an ionic radius above 1.0 Å. This is as would be expected from the fact that HQC forms two five-membered chelate rings on complex-formation, which favors larger metal ions. The ligand design concept of using rigid aromatic backbones in ligands to achieve high levels of preorganization, and hence the high log K values (for a tridentate ligand) and strong metal ion selectivities observed for HQC, is discussed.  相似文献   


9.
Benzene solutions of Cp*2ZrCl2 (1) (Cp* = η5-C5Me5) react with the alkynes Me3SiC≡CPh, Me3SiC≡C(c-C5H9) and Me3SiC≡CCMe3 in the presence of Na/Hg amalgam to afford high yields of the respective alkyne complexes Cp*2Zr(Me3SiC≡CPh) (2), Cp*2Zr{Me3SiC≡C(c-C5H9)} (3) and Cp*2Zr(Me3SiC≡CCMe3) (4) as crystalline compounds. Complex 2 crystallizes in the triclinic space group with a = 9.791(6), b = 10.466(6), c = 15.756(12) Å, = 86.09 (5), β = 72.09(5), γ = 72.06(4)° and Z = 2. The least-squares refinement converged to R(F) = 0.0604 and R(wF) = 0.0628 for the 3655 unique data with Fo > 4σ (Fo). Salient metrical parameters of the bound alkyne include the following: C(30)-C(31) = 1.340(9) Å; Zr-C(30) = 2.178(6) Å; Zr-C(31) = 2.219(5) Å; C(30)-C(31)-Si = 141.0(5)°; C(31)-C(30)-C(26) = 135.5(5)°. Nitrous oxide reacts with 2 or 3 to afford ((5) R = Ph; (6) R = c-C5H9) and 1 equiv. of N2 via an intermediate, , which is unstable with respect to loss of dinitrogen to give the oxametallacyclobutene derivatives 5 and 6. The oxygen-atom insertion is regiospecific for the Zr-C bond that is attached to the carbyl (Ph or c-C5H9) substituent. Under similar conditions, complex 4, in which the alkyne is particularly labile, gives a myriad of products in its reaction with N2O.  相似文献   

10.
The crystal structures of Li[Fe(trtda)]·3H2O and Na[Fe(eddda)]·5H2O (trtda = trimethylenediaminetetraacetate and eddda = ethylenediamine-N,N′-diacetate-N,N′-di-3-propionate) have been determined by single crystal X-ray diffraction techniques. The former crystal was monoclinic with the space group P21/n,a = 17.775(3),b = 10.261(1),c = 8.883(2)Å, β = 95.86(4)° and Z = 4. The latter was also monoclinic with the space group P21/n,a = 6.894(2),b = 20.710(6),c = 13.966(3)Å, β = 101.44(2)° and Z = 4. Both complex anions were found to adopt an octahedral six-coordinated structure with all of six ligand atoms of trdta4− or eddda4− coordinated to the Fe(III) ion, unlike the corresponding edta4− complex which is usually seven-coordinate with the seventh coordination site occupied by H2O. Of the three geometrical isomers possible for the eddda complex, the trans(O5) isomer was actually found in the latter crystal. Factors determining the structural types of metal–edta complexes are discussed in detail.  相似文献   

11.
The new disymmetric ligand N,N,N′-tris(2-pyridylmethyl)-N′-(2-salicylideneethyl)ethane-1,2-diamine (LH) has been synthesized in the search of a novel type of manganese complex to mimic the active site of the water-oxidizing enzyme in photosystem II. The complex [Mn(II)L]ClO4 has been obtained and characterized by X-ray diffraction techniques. It crystallizes in the monoclinic space group Pn with the following unit cell parameters: a=10.164(3), b=10.122(4), c=14.166(5) Å, β=93.48(2)° and Z=2. The manganese ion is heptacoordinated with the coordination being achieved by only one ligand; it is bonded to the oxygen atom of the phenolate group in an axial position, the imino and the three pyridine nitrogen atoms in an equatorial position and the two amine atoms in a pseudo-axial position. The coordination polyhedron is best described as a distorted monocapped trigonal prism. This structure was compared with the seven-coordinated Mn(II) complexes deposited in the Cambridge Structured Database (CSD). The redox potential of the Mn(III)/Mn(II) couple was determined by cyclic voltammetry.  相似文献   

12.
The Schiff base formed by condensation of 2,6-diacetylpyridine with S-benzyldithiocarbazate (H2SNNNS) behaves as a pentadentate ligand, forming a nickel(II) complex of empirical formula Ni(SNNNS)·H2O that is high-spin with a room-temperature magnetic moment of 2.93 B.M. Spectroscopic data indicate that the ligand coordinates with the nickel(II) ion via the pyridine nitrogen atom, the azomethine nitrogen atom and the thiolate sulfur atom. The crystal and molecular structure of the nickel(II) complex was determined by X-ray crystallography. The complex crystallizes in the monoclinic system, space group C2/c, with a=15.849(2), b=18.830(2) and c=18.447(2) Å and =90°, β=102.179(6)°, γ=90° and Z=8. The crystal structure analysis shows that the complex is dinuclear, [Ni(SNNNS)]2·2H2O, in which the nickel(II) ions are bridged by the two pyridine nitrogen atoms of two fully deprotonated ligands. The NiN4S2 coordination geometry about each nickel(II) ion can be described as a distorted octahedron. The Schiff base and its nickel(II) complex were tested against four pathogenic bacteria (Bacillus subtilis, Pseudomonas aeruginosa, methicillin-resistant Staphylococcus and B. subtilis (wild type B29) and pathogenic fungi (Saccharomyces ceciricae, Candida albicans, Candida lypolitica and Aspergillus ochraceous) to assess their antimicrobial properties. Both compounds exhibit mild antibacterial and antifungal activities against these organisms. The anticancer properties of these compounds were also evaluated against Human T-lymphoblastic leukaemia cell lines. The Schiff base exhibits marked cytotoxicity against these cells, but its nickel(II) complex is inactive.  相似文献   

13.
Treatment of the A-ring aromatic steroids estrone 3-methyl ether and β-estradiol 3, 17-dimethyl ether with Mn(CO)5+BF4 in CH2Cl2 yields the corresponding [(steroid)Mn(CO)3]BF4 salts 1 and 2 as mixtures of and β isomers. The X-ray structure of [(estrone 3-methyl ether)Mn(CO)3]BF4 · CH2Cl2 (1) having the Mn(CO)3 moiety on the side of the steroid is reported: space group P21 with a=10.3958(9), b=10.9020(6), c=12.6848(9) Å, β=111.857(6)°, Z=2, V=1334.3(2) Å3, calc=.481 cm−3, R=0.0508, and wR=0.0635. The molecule has the traditional ‘piano stool’ structure with a planar arene ring and linear Mn---C---O linkages. The nucleophiles NaBH4 and LiCH2C(O)CMe3 add to [(β-estradiol 3,17-dimethyl ether)Mn(CO)3]BF4 (2) in high yield to give the corresponding - and β-cyclohexadienyl manganese tricarbonyl complexes (3). The nucleophiles add meta to the arene -OMe substituent and exo to the metal. The and β isomers of 3 were separated by fractional crystallization and the X-ray structure of the β isomer with an exo-CH2C(O)CMe3 substituent is reported (complex 4): space group P212121 with a=7.5154(8), b=15.160(2), c=25.230(3) Å, Z=4, V=2874.4(5) Å3, calc=1.244 g cm−3, R=0.0529 and wR2=0.1176. The molecule 4 has a planar set of dienyl carbon atoms with the saturated C(1) carbon being 0.592 Å out of the plane away from the metal. The results suggest that the manganese-mediated functionalization of aromatic steroids is a viable synthetic procedure with a range of nucleophiles of varying strengths.  相似文献   

14.
The synthesis of the tetradentate pendant arm macrocycles 1,4,7-triazacyclononane-N-acetate (L1) and N-(2-hydroxybenzyl)-1,4,7-triazacyclononane (HL2) and their coordination chemistry with vanadium(IV) and (V) are reported. The following mononuclear species have been prepared and characterized by UV-Vis, IR spectroscopy: [L1VIVO(NCS)] (1), [L1VO2]·H2O (2), [L2VO(NCS)] (3), [L2VO(NCS)]Cl (4), and [L2VO2] (5). In addition, the dinuclear, mixed valent complexes [L21V2O3]Br (6), [L22V2O3](ClO4)·0.5acetone (7), and the homovalent complex [L22V2O3](ClO4)2 (8) have been synthesized. Complexes 2, 3, 6 and 7 have been characterized by single crystal X-ray crystallography. Crystal data: 2, space group P21c,a=9.944(4),b=6.701(3),c=18.207(8)Å, β=102.88(3)°, V=1182.7 Å3, Z=4, Dcalc=1.51 g cm−3, R=0.049 based on 4760 reflections; 3, space group Pbca, A=11.003(6), b=14.295(7), C=20.21(1) Å, V=3178.8 Å3, Z=8, Dcalc=1,50 g cm−3, R=0.057 based on 1049 reflections; 6, space Pbcn, a=12.922(3), B=13.852(3), C=12.739(3) Å, V=2280.3 Å3, Z=4, Dcalc=1,75 g cm−3, R=0.047 based on 1172 reflections; 7, space group C2/c, A=23.553(9), B=13.497(5), C=20.951(8) Å, β=90.03(3)°, V=6660.2 Å3, Z=8, Dcalc=1.49 g cm−3, R=0.053 based on 3698 reflections. Complexes 6 and 7 are mixed valent V(IV)/(V) complexes containing the [OV---O---VO]3+ core. In the solid state 6 belongs to class III (delocalized) and 7 to class I (localized) according to the Robin and Day classification of mixed valent compounds. A rationale for these differing electronic structures is given.  相似文献   

15.
Tricarbonyl-η5-2,4-dimethyl-2,4-pentadien-1-yl-manganese (1) forms upon UV irradiation in THF at 208 K solvent stabilized dicarbonyl-η5-2,4-dimethyl-2,4-pentadien-1-yl-tetrahydrofurane-manganese (2). With butynedioic acid dimethyl ester (3) and diphenylacetylene (5) complex 2 yields tricarbonyl-η5-1,2-dimethoxycarbonyl-4,6-dimethyl- cyclohepta-2,4-dien-1-yl-manganese (4) and tricarbonyl-η-4,6-dimethyl-1,2-diphenyl-cyclohepta-2,4-dien-1-yl- manganese (6) in a formal [5+2] cycloaddition. Addition of carbon monoxide and a 1,4-H shift completes the reaction. Propynoic acid methyl ester (7) forms the 2:1 adduct dicarbonyl-η5:2-1,3-dimethyl-6-methoxycarbonyl-6- (E-2′-methoxycarbonylvinyl)-cyclohepta-2,4-dien-1-yl-manganese (8). The crystal and molecular structure of 8 was determined by X-ray structure analysis. The molecular structures of the complexes 4 and 6 were established by IR and NMR spectroscopy. Formation mechanisms of 4, 6 and 8 are discussed. Crystal data for 8: monoclinic space group P21/c, a=802.6(3), b=1136.6(1), c=8872.3(3) pm, β=93.14(2)°, V=1.705 nm3, Z=4.  相似文献   

16.
Rapid reactions occur between [OsVI(tpy)(Cl)2(N)]X (X = PF6, Cl, tpy = 2,2′:6′,2″-terpyridine) and aryl or alkyl phosphi nes (PPh3, PPh2Me, PPhMe2, PMe3 and PEt3) in CH2Cl2 or CH3CN to give [OsIV(tpy)(Cl)2(NPPh3)]+ and its analogs. The reaction between trans-[OsVI(tpy)(Cl)2(N)]+ and PPh3 in CH3CN occurs with a 1:1 stoichiometry and a rate law first order in both PPh3 and OsVI with k(CH3CN, 25°C) = 1.36 ± 0.08 × 104 M s−1. The products are best formulated as paramagnetic d4 phosphoraniminato complexes of OsIV based on a room temperature magnetic moment of 1.8 μB for trans-[OsIV(tpy)(Cl)2(NPPh3)](PF6), contact shifted 1H NMR spectra and UV-Vis and near-IR spectra. In the crystal structures of trans-[OsIV(tpy)(Cl)2( NPPh3)](PF6)·CH3CN (monoclinic, P21/n with a = 13.384(5) Å, b = 15.222(7) Å, c = 17.717(6) Å, β = 103.10(3)°, V = 3516(2) Å3, Z = 4, Rw = 3.40, Rw = 3.50) and cis-[OsIV(tpy)(Cl)2(NPPh2Me)]-(PF6)·CH3CN (monoclinic, P21/c, with a = 10.6348(2) Å, b = 15.146(9) ÅA, c = 20.876(6) Å, β = 97.47(1)°, V = 3334(2) Å3, Z = 4, R = 4.00, Rw = 4.90), the long Os-N(P) bond lengths (2.093(5) and 2.061(6) Å), acute Os-N-P angles (132.4(3) and 132.2(4)°), and absence of a significant structural trans effect rule out significant Os-N multiple bonding. From cyclic voltammetric measurements, chemically reversible OsV/IV and OsIV/III couples occur for trans-[OsIV(tpy)(Cl)2(NPPh3)](PF6) in CH3CN at +0.92 V (OsV/IV) and −0.27 V (OsIV/III) versus SSCE. Chemical or electrochemical reduction of trans-[OsIV(tpy)(Cl)2(NPPh3)](PF6) gives isolable trans-OsIII(tpy)(Cl)2(NPPh3). One-electron oxidation to OsV followed by intermolecular disproportionation and PPh3 group transfer gives [OsVI(tpy)Cl2(N)]+, [OSIII(tpy)(Cl)2(CH3CN)]+ and [Ph3=N=PPh3]+ (PPN+). trans-[OsIV(tpy)(Cl)2(NPPh3)](PF6) undergoes reaction with a second phosphine under reflux to give PPN+ derivatives and OsII(tpy)(Cl)2(CH3CN) in CH3CN or OsII(tpy)(Cl)2(PR3) in CH2Cl2. This demonstrates that the OsVI nitrido complex can undergo a net four-electron change by a combination of atom and group transfers.  相似文献   

17.
A new method has been developed for the preparation of nitroaryl transition metal complexes using copper(II) nitrate in the presence of acetic anhydride (Menke conditions) to directly nitrate an aryl group which is already σ-bound to a transition metal centre. Under these conditions ruthenium(II) aryl complexes of the type: (where R1=R2=H; R1=H, R2=CH3; R1=CH3, R2=H) react to yield three distinct types of nitroaryl-containing products (I–III).

The preparation and characterisation of these compounds are described. X-ray crystallographic data for one example of each of the three types of compound, are also reported. The compounds that have been studied crystallographically are Ru(C6H4NO2-4)(η2-O2CCH3)(CO)(PPh3)2 (1a), C45H37NO5P2Ru·(CH2Cl2)0.5, a = 20.254(5), b=19.437(8), c=22.629(3) Å, β=115.390(10)°, monoclinic, space group C2/c, Z=8; Ru(C6H4N[O]O-2)- Cl(CO)(PPh3)2 (4a), C43H34ClNO3P2Ru, a=9.331(3), b=12.443(2), c=16.346(3) Å, =82.81(2), β=85.03(2), γ=74.76(2)°, triclinic, space group P , Z=2; Ru(C6H2CH3-2,NO2-4,N[O]O-6)Cl(CO)(PPh3)2 (5b), C44H35Cl- N2O5P2Ru·(CH2Cl2)2, a=19.497(3), b=14.502(3), c=19.340(5) Å, β=122.79(1)°, monoclinic, space group Cc, Z=4.  相似文献   


18.
Two novel, weakly antiferromagnetically coupled, tetranuclear copper(II) complexes [Cu4(PAP)22-1,1-N3)22-1,3-N3)22-CH3OH)2(N3)4 (1) (PAP = 1,4-bis-(2′-pyridylamino)phthalazine) and [Cu4(PAP3Me)22-1,1-N3)22-1,3-N3)2(H2O)2(NO2)2]- (NO3)2 (2) (PAP3Me = 1,4-bis-(3′-methyl-2′-pyridyl)aminophthalazine) contain a unique structural with two μ2-1,1-azide intramolecular bridges, and two μ2-1,3-azide intermolecular bridges linking pairs of copper(II) centers. Four terminal azide groups complete the five-coordinate structures in 1, while two terminal waters and two nitrates complete the coordination spheres in 2. The dinuclear complexes [Cu2(PPD)(μ2-1,1-N3)(N3)2(CF3SO3)]CH3OH) (3) and [Cu2(PPD)(μ2-1,1-N3)(N3)2(H2O)(ClO4)] (4) (PPD = 3,6-bis-(1′-pyrazolyl)pyridazine) contain pairs of copper centers with intramolecular μ2-1,1-azid and pyridazine bridges, and exhibit strong antiferromagnetic coupling. A one-dimensional chain structure in 3 occurs through intermolecular μ2-1,1-azide bridging interactions. Intramolecular Cu-N3-Cu bridge angles in 1 and 2 are small (107.9 and 109.4°, respectively), but very large in 3 and 4 (122.5 and 123.2°, respectively), in keeping with the magnetic properties. 2 crystallizes in the monoclinic system, space group C2/c with a = 26.71(1), b = 13.51(3), c = 16.84(1) Å, β = 117.35(3)° and R = 0.070, Rw = 0.050. 3 crystallizes in the monoclinic system, space group P21/c with a = 8.42(1), b = 20.808(9), c = 12.615(4) Å, β = 102.95(5)° and R = 0.045, Rw = 0.039. 4crystallizes in the triclinic system, space group P1, with a = 10.253(3), b = 12.338(5), c = 8.072(4) Å, = 100.65(4), β = 101.93(3), γ = 87.82(3)° and R = 0.038, Rw = 0.036 . The magnetic properties of 1 and 2 indicate the presence of weak net antiferromagnetic exchange, as indicated by the presence of a low temperature maximum in χm (80 K (1), 65 K (2)), but the data do not fit the Bleaney-Bowers equation unless the exchange integral is treated as a temperature dependent term. A similar situation has been observed for other related compounds, and various approaches to the problem will be discussed. Magnetically 3 and 4 are well described by the Bleaney-Bowers equation, exhibiting very strong antiferromagnetic exchange (− 2J = 768(24) cm−1 (3); − 2J = 829(11) cm−1 (4)).  相似文献   

19.
A series of square-planar complexes [MLCl]ClO4 (M = Pd(II), Pt(II); L = bis(3-(diphenylphosphino)propyl)sulfide (psp), bis(3-(diphenylarsino)propyl)sulfide (asa)) have been prepared and characterized. The X-ray crystal structures of two of them have been determined: [Pd(psp)Cl]ClO4, P21/c, A = 12.519(2), B = 15.766(2), C = 16.501(2) Å, β = 105.22(1)°, Z = 4; and [Pt(asa)Cl]ClO4, P21/c, a = 12.583(5), B = 16.007(6), C = 16.549(6) Å, β = 104.89(3)°, Z = 4. In both structures, there is a conformational disorder between the chair and skew-boat orientation in one of the two six-membered chelate rings. The C---H…O hydrogen bond between the hybrid ligand and the perchlorate counter ion that induces the conformational disorder is discussed.  相似文献   

20.
The cyclocondensation of 2,5-diformylthiophene and the amines N,N-bis-(2-aminoethyl)-2-phenylethylamine, N,N-bis-(2aminoethyl)-t-butyl-amine and N,N-bis-(2-aminoethyl)-t-butyl-amine in the presence of silver(I) salts yields homodinuclear bibracchial tetraimine Schiff base macrocyclic complexes. The structures of two such complexes are also reported. The complex Ag2L4(NO3)(PF6) (2) crystallises in the triclinic space group , No. 2) and has unit-cell dimensions a = 12.834(6), B = 13.183(6), C = 14.588(7) Å, = 64.86(4), β = 79.77(4), γ = 69.44(3)° with Z = 2; there is a monodentate and singly bridging nitrate anion present and the Ag---Ag separation is 4.161 Å. The complex Ag2L4(CH3CN)2(BF4)2·CH3CN (9) crystallises in the triclinic space group , No. 2) and has unit-cell dimensions a = 9.297(4), B = 12.985(3), C = 21.770(5) Å, = 91.570(10), β = 92.33(3), γ = 97.92(3) ° with Z = 2; there is a strongly bonded acetonitrile molecule coordinated to each silver atom and the Ag---Ag separation is 4.920 Å.  相似文献   

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