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1.
Pentaammineosmium(III) coordinates to both the N7 and C8 positions of purine rings. The compound 7-[9MeHyp(NH3)5Os]Cl3·H2O crystallizes in the orthorhombic space group Pnma (No. 62) with the unit cell parameters: a=11.542(2), b=6.9841(8), c=21.960(3) Å and Z=4. The compound 8-[1,3,7Me3Xan(NH3)5Os]Cl3·2H2O crystallizes in the monoclinic space group P21/c (No. 14) with the unit cell parameters: a=7.1228(X), b=14.613(1), c=19.667(1) Å, β=91.782(9)° and Z=4. The Os---C bond in the latter structure is 2.039(9) Å and the imidazolylidine ligand exerts a slight trans influence seen in the lengthening of the Os---Nax distance (2.172(8) Å) by about 0.05 Å relative to the average of the equatorial Os---Neq value of 2.123(8) Å. The spectroscopic, electrochemical and structural properties of these and additional N-bound purine complexes are compared with those of similar N7 and C8 ruthenium(III) species.  相似文献   

2.
Bis(pentamethylcyclopentadienyl)samarium bis- (tetrahydrofuranate), (C5Me5)2Sm(THF)2, reacts with 2,3,5,6-tetramethylphenol in toluene to yield (C5Me5)2Sm(OC6HMe4-2,3,5,6). The compound crystallizes in the space group P21/c with a = 8.725(3) Å, b=18.821(6) Å, c=18.461(6) Å, β= 111.17(2)°, V = 2827(2) Å3 and Dc=1.340 g cm−3 for Z = 4. Molecules of the aryloxide complex are monomeric and exhibit a bent metallocene structure with a nearly linear Sm---O---C(aryloxide) linkage: Sm---O = 2.13(1) Å, O---C = 1.29(2) Å, and Sm---O---C = 172.3(13)°. Reaction of the samarium complex with phenyllithium produces the previously- characterized species (C5Me5)2Sm(C6H5)(THF).  相似文献   

3.
The synthesis, crystal structure determination and magnetic properties of a new five-coordinated unsymmetrical copper(II) dinuclear complex [Cu2Cl3(C7H6N2)5]Cl·4H2O are reported. The crystals are orthorhombic, space group Pnma with 4 formula units in a cell of dimensions: a = 19.506(3), b = 17.384(4), C = 11.940(2) Å. The structure was solved by direct methods. Least-squares refinement using 2138 independent reflections with I3σ(I) has led to a final value of the conventional R factor (on F) of 0.047 and Rw of 0.049. The complex cation consists of pairs of deformed trigonal-bipyramidal copper(II) centers which share an edge by two equatorial chloride ions. The equatorial coordination sites of the Cu(1) atom are occupied by three chloride ligands, while of the Cu(2) atom by two chloride and one benzimidazole ligands. The axial sites are occupied by the nitrogen atoms from four benzimidazole ligands. The Cu atoms and equatorial ligands are located on the symmetry plane. The Cu---Cu non-bonding distance in the complex is 3.386(1) Å; the two shorter bridging Cu(1)---Cl(1) and Cu(2)---Cl(1) distances are 2.402(2) and 2.424(2) Å; the two longer Cu(1)---Cl(2) and Cu(2)---Cl(2) are 2.620(2) and 2.551(2) Å. The Cu(1)---Cl(1)---Cu(2) and Cu(1)---Cl(2)---Cu(2) angles are 89.1(1) and 81.8(1)°. The structure is the first example of a bibridged binuclear complex with two non-equivalent Cu---Cl---Cu bridges. Comparison to other binuclear bis(μ-halide)-bridged copper complexes of similar structure has been made. Magnetic susceptibility measurements indicate ferromagnetic coupling of the copper(II) centers, the intramolecular exchange parameter, 2J, being 5.6 cm−1 and the intermolecular one J′ = −0.6 cm−1. The investigation of the electronic structure of the complex and the orbital interpretation of the magnetic coupling based on extended Hückel molecular orbital calculations are also presented.  相似文献   

4.
The preparation and X-ray structure of [Ag(9-EtGH-N7)2]NO3·H2O(9-EtGH=neutral 9-ethylguanine) is reported. The compound crystallizes in the triclinic system, space group P with a=7.063(6), b=7.153(3), c=11.306(10) Å, α=83.36(6), β=76.66(7), γ=81.44(6)°. The cation is centrosymmetric with Ag(I) coordinated via two N7 positions and Ag---N7 bond lengths of 2.11(1) Å. Applying 109Ag NMR spectroscopy, complex formation constants for both the 1:1 complex (log β1=0.6) and the title compound (log β2=1.6) in Me2SO have been determined.  相似文献   

5.
The reaction of α-MgCl2 with boiling ethyl acetate affords MgCI2(CH3COOC2H5)2· (CH3COOC2H5), which is obtained as crystals suitable for X-ray analysis only from the mother liquor. M=315.5, orthorhombic, space group P21221 (No. 18), a=25.077(3), b=8.616(1), c=7.345(1) Å, V=1587.0(3) Å3, Z=4, Dx=1.32 g cm−3,λ A(Mo Kα)=0.71069 Å, μ=4.17 cm−1, F(000)=664, T=298 K, observed reflections: 1667, R=0.059 and Rw=0.069. The structure is composed of polymeric chains of MgCl2(CH3COOC2H5)2 and the ethyl acetate molecules occupy a mutually trans position.  相似文献   

6.
The reactions of lithium(diphenylphosphino)tetramethylcyclopentadienide with CpTiCl3 and secondly with TiCl3 followed by CCl4 oxidation lead to the formation of two titanocene phosphines: (η5-C5H5)[η5-C5Me4P(C6H5)2]TiCl2 (2) and [η5-C5Me4P(C6H5)2]2TiCl2 (3), respectively. The metalloligand 3 reacts readily with Mo(CO)4cod, Mo(CO)5THF and Mo(CO)6 to give in each case [(η5-C5Me4 o(CO)4 (6) as a sole product. The structure of 6 has been determined by X-ray diffraction. Crystal data: P , a = 11.716(1), b = 11.753(2), c = 16.110(2) Å, α = 99.06(1), β = 92.61(1), γ = 104.20(1)°, Z = 2. The molybdenum-titanium distance of 5.194(1) Å rules out any metal-metal interaction. The chlorine substitution reactions by CO in 2 and 3 and by thiolate group (pH3C-C6H4-S) in 16 are reported.  相似文献   

7.
Uranyl complexes of glycine, β-alanine and γ-aminobutanoic acid were prepared and characterized. All those studied or examined contain the aminoacids in the zwitterionic form binding the metal through the ionized carboxyl group. The structure of the title compound was determined by X-ray crystallography and refined to R=6.6%. The crystals are triclinic, space group P1, Z = 2, with a = 11.966(5), b = 12.054(5), c = 10.581(5) Å, α = 70.88(3)°, β = 109.89(3)°, and γ = 120.72(3)°. The uranyl group is equatorially bonded to the bidentate carboxylate of three molecules of the organic ligand forming a distorted hexagonal bipyramidal coordination geometry around the metal. U---O(equatorial) distances are in the range 2.24–2.48 Å.  相似文献   

8.
The reaction of iron(III) acetylacetonate with zirconium(IV) n-propanolate in n-propanol leads to a tetranuclear species Zr3FeO(OC3H7)10(acac)3. This compound crystallizes in the triclinic system (space group P ): a = 12.426(2), b = 12.977(2), c = 20.129(4) Å, α = 91.55(1), β = 97.90(1), γ = 100.53(1)°. The structure consists of discrete tetranuclear molecules. The metal atoms design an almost perfect tetrahedron around a four-fold coordinated oxygen atom. The zirconium atoms are in a seven-fold coordination and the iron atom in a five-fold coordination.  相似文献   

9.
The 1,3-oxazine complexes cis- and trans-[PtCl2{ C(R)OCH2CH2C}H22] (cis: R=CH3 (1a), CH2CH3 (2a), (CH3)3C (3a), C6H5 (4a); trans:R =CH3 (1b), C6H5 (4b)) were obtained in 51-71% yield by reaction in THF at 0 °C of the corresponding nitrile complexes cis- and trans-[PtCl2(NCR)2] with 2 equiv. of OCH2CH2CH2Cl, generated by deprotonation of 3-chloro-1-propanol with n-BuLi. The cationic nitrile complexes trans-[Pt(CF3)(NCR)(PPh3)2]BF4 (R=CH3, C6H5) react with 1 equiv, of OCH2CH2CH2Cl to give a mixture of products, including the corresponding oxazine derivatives trans-[Pt(CF3){ CH2}(PPh3)2]BF4 (5 and 6), the chloro complex trans- [Pt(CF3)Cl(PPh3)2] and free oxazine H2. For short reaction times (c. 5–15 min) the oxazine complexes 5 and 6 could be isolated in modest yield (37–49%) from the reaction mixtures and they could be separated from the corresponding chloro complex (yield 40%) by taking advantage of the higher solubility of the latter derivative in benzene. For longer reaction times (> 2 h), trans-[Pt(CF3)Cl(PPh3)2] was the only isolated product. Complex 6 was crystallographically characterized and it was found to contain also crystals of trans- [PtCl{ H2}(PPh3)2]BF4, which prevented a more detailed analysis of the bond lengths and angles within the metal coordination sphere. The 1,3-oxazine ring, which shows an overall planar arrangement, is characterized by high thermal values of the carbon atoms of the methylene groups indicative of disordering in this part of the molecule in agreement with fast dynamic ring processes suggested on the basis of 1H NMR spectra. It crystallizes in the trigonal space group P , with a=22.590(4), b=15.970(3) Å, γ=120°, V=7058(1) Å3 and Z=6. The structure was refined to R=0.059 for 3903 unique observed (I3σ(I)) reflections. A mechanism is proposed for the conversion of nitrile ligands to oxazines in Pt(II) complexes.  相似文献   

10.
1-Methylimidazoline-2(3H)-thione (mimtH) and copper(I) thiocyanate in refluxing ethanolacetonitrile produce a colourless, diamagnetic complex, [Cu2(mimtH)4(SCN)2], which crystallises in an orthorhombic cell (a=8.0724(3), b=15.9545(6), c=21.3357(8) Å), space GROUP=Pbca, Z=4, final R=0.0319 from 2427 observed reflections F>4σc(F)). In the dimeric complex the copper(I) atoms are pseudo-tetrahedrally coordinated by pairs of, respectively, asymmetrically μ2-S bridging mimtH, terminal monodentate-S mimtH, (Cu---S=2.290(1) Å), and terminal monodentate-S thiocyanate, (Cu---S=2.332(1) Å). Each pair of ligands is trans-related to its partner across crystallographic centres of symmetry, consequently, each copper(I) atom has an identical S4 donor set with angles at the metal ranging from 95.9(1)° to 121.8(1)°. The centro-symmetric Cu2S2 core is rhomboid with Cu---S=2.377(1) and 2.457(1) Å, Cu---Sbr---Cu=72.6(1)° and Cu---Cu, Sbr---Sbr separation distances of 2.861(1) and 3.897(2) Å, respectively. Thermal decomposition of the complex in flowing air, (133–1000 °C), involves de-sulfurisation of mimtH and thiocyanate with concomitant production of copper(II) sulfide followed by oxidation to copper(II) oxide.  相似文献   

11.
The copper(II), nickel(II) and silver(I) complexes of the pentadentate 17-membered macrocycle 1, 12, 15-triaza-3, 4:9, 10-dibenzo-5,8-dithiacycloheptadecane (L1) have been prepared as perchlorates and characterized by X-ray crystallography. The N3S2 ligand uses all donor atoms for complexation. The copper coordination is square pyramidal with one sulfur atom in the axial site. Ni(II) displays an octahedral coordination by an interaction with a water molecule. The Ag(I) coordination is best described as a distorted pentagonal bipyramid. In [CuL1]2+ the 1, 4, 7-triazaheptane fragment of L1 is meridionally coordinated, but facially in [NiL1(H2O)]2+ and intermediate in [AgL1](ClO4). Crystal data for [CuL1](ClO4)2: monoclinic, space group P21/n, a = 13.153(8), b = 11.951(5), c = 17.880(8)Å, β = 110.29(4)°, Z = 4, R = 0.086 for 2732 independent reflections with I 2σ(I); [NiL1(H2O)](ClO4)2: monoclinic, P21/a, a = 10.771(2), b= 16.157(2), c = 15.286(2) Å, β =93.08(1)°, Z = 4, R = 0.085 for 1464 independent reflections with I 2σ(I); [AgL1](ClO4): monoclinic, P21/n, a = 12.708(9), b = 9.483(7), c = 19.569(13) Å, β= 103.95(6)°, Z = 4, R = 0.039 for 3600 independent reflections with I 2σ(I).  相似文献   

12.
The reactive palladium dimer, [Pd(dppm)(O2CCF3)]2, is carbonylated to [Pd(dppm)(O2CCF3)]2(μ-CO) in a reversible reaction with K = c. 7.2(2)x104 atm−1 (P1/2 = c. 2.4 Torr). This is significantly larger than is expected based on the λmax = 280 nm in the electronic spectrum. The product can be isolated in analytically pure form by crystallization under a CO atmosphere. It forms crystals in the monoclinic space group Cc with a = 18.584(5), b = 28.65(1), c = 11.164(3) Å and β = 95.16(2)°. The structure is significantly distorted. The bonding about the two palladium atoms is quite asymmetric. While one is close to a square planar geometry with a Pd---C(O) distance of 1.90(2) Å, the other is significantly pyramidalized and has a longer (2.00(2) Å) bond to the bridging CO. The Pd---Pd distance is only 2.896(2) Å, much shorter than that usually observed for formally non-bonded Pd atoms.  相似文献   

13.
The reaction of [Mo2Cl4(μ-S2)(μ-2-SC5H3NH-3-SiMe3)(2-SC5H3N-3-SiMe3)2] with phenylhydrazine yields [Mo(NNPh)(2-SC5H3N-3-SiMe3)3] (1). Complex 1 adopts a pentagonal bipyramidal geometry with the phenyldiazenido group occupying an axial position. The structural parameters exhibited by 1 are similar to those of other members of the class of seven coordinate Mo-hydrazido and Mo-diazenido species. Crystal data for C30H41N5Si3S3Mo (1): monoclinic space group P21n, a = 11.600(2), b = 14.880(3), c = 21.681(3) Å, β = 90.46(1)°, V = 3242.2(12) Å3, Z = 4; 5690 reflections, R = 0.049.  相似文献   

14.
(Ph4P)4[Tl4Se16] was prepared hydrothermally in a sealed pyrex tube by the reaction of TlCl, K2Se4 and Ph4PCl in a 1:1:1 molar ratio at 110 °C for one day. The red crystals were obtained in 50% yield. Crystals of (Ph4P)4[Tl4Se16]: triclinic P (No. 2), Z=1, a=12.054(9), b=19.450(10), c=11.799(6) Å, α=104.63(4), β=98.86(6), γ=101.99(6)° and V=2555(3) Å3 at 23 °C, 2θmax=40.0°, μ=120.7 cm−1, Dcalc=2.23. The structure was solved by direct methods. Number of data collected: 5206. Number of unique data having Fo2>3σ(Fo2): 1723. Final R=0.075 and Rw=0.089. [Tl4Se16]4− consists of four, almost already linearly arranged, tetrahedral thallium centers which are coordinated by two chelating Se42−, two bridging Se22− and four bridging Se2− ligands. [Tl4Se16]4− sits on an inversion center and possesses a central {Tl2Se2}2+ planar core. The Tl(1)–Tl(1)′ distance in this core is 3.583(6) Å. These two thallium atoms are then each linked to two cyclic Tl(Se4) fragments via bridging Se22− and Se2− ligands forming Tl2Se(Se2) five-membered rings.  相似文献   

15.
Synthesis and characterisation of the new macrocyclic ligand 1,7-dimethyl-4,10-di(methylcarbamoylmethy)-1,4,7,10-tetraazacyclododecane (L) are reported. The ligand, based on cyclen (1,4,7,10-tetraazacyclododecane), has been functionalised by the insertion of two methyl groups and two amidic pendant arms linked to the amine nitrogens. The interaction of L with H+, Na(I), Ca(II), Cu(II), Zn(II), Pb(II), and Gd(III) ions has been studied by potentiometric titrations, microcalorimetric and 1H NMR measurements in 0.1 mol dm−3 Me4NCl aqueous solution at 298.1±0.1 K. The thermodynamic data suggest that the N4 moiety is the binding site for Cu(II) and Zn(II), while in the case of Pb(II) also the pendant arms are coordinated to the metal ion. The crystal structure of [PbL](ClO4)2 (space group P21/a, a=12.883(2) Å, b=12.259(3) Å, c=17.275(5) Å, β=108.65(2)°, V=2585.0(11) Å3, Z=4, R=0.0660, RW 2=0.1467) shows the metal ion hexa-coordinated by the four nitrogen atoms of the cyclic tetra-amine and by the two amidic oxygens of the pendant arms.  相似文献   

16.
The reaction of mercaptoacetyl diglycine (MAG2) with technetium(V) gluconate in aqueous solution produced [TcO(MAG2)]. A single X-ray structure determination was carried out for the tetraphenylarsonium salt. The dark brown crystals are monoclinic, space group P2(1)/n, with a=12.478(5), b=14.922(5), c=17.183(9) Å and Z=4. The [TcO(MAG2)] ion has a square pyramidal geometry with the technetium atom displaced by 0.756 Å towards the oxo ligand from the plane formed by the equatorial S,N,N,O atoms. The rhenium complex AsPh4[ReO(MAG2)] was prepared analogously starting from Re(V) gluconate and characterized.  相似文献   

17.
An X-ray structural analysis of bis-2,2′,N,N′-bipyridyl ketone cobalt(III) nitrate dihydrate, CoC22H20N4O4+· NO3·2H2O,Mr=559.38 g/mol, P , a=8.862(2), b=16.195(3), c=8.772(2) Å, α=103.54(2), β=95.74(3), γ=105.07°, V=1164.4(4) Å3, Z=2, Dx=1.595 g/cm3, Mo Kα radiation (λ=0.71073 Å), μ=7.8 cm−1 and R=0.079, revealed a Co(III) cation in a slightly distorted octahedral environment. The structure reveals that the ligand di-2-pyridyl ketone (dpk) has undergone a hydration reaction across the ketone double bond and one of the hydrate oxygen atoms coordinated to the metal forming a tridentate chelate. This new Co(dpk-hydrate)2+ complex displays the least distorted geometry yet reported for either 1:1 or 1:2 (metal:ligand) complexes. A geometry optimization using the INDO model Hamiltonian as implemented in the program ZINDO was performed on the title complex with the Co3+ modeled as a singlet. The result of the computation corroborates the geometry of the title complex as that expected for Co3+.  相似文献   

18.
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   

19.
Reaction of 9-methyl-1-deazapurine (9-MeDP) with Hg(CF3COO)2 in the presence of NaNO3 yields the title compound [Hg(9-MeDP)2](NO3)2 · H2O with the two 9-MeDP ligands bound to the metal ion via their N7 positions. The X-ray structure is reported: monoclinic, P21/c (no. 14), a = 5.4015(11), b = 20.467(4), c = 17.775(4) Å, β = 97.00(3)°, V = 1950.4(7) Å3, Z = 4. Hg is eight-coordinate with two trans-oriented Hg-N bonds (2.073(3) and 2.075(3) Å) and three nearly coplanar, bidentate nitrate moieties (Hg-O: 2.716(3)-2.985(4) Å), leading to a distorted hexagonal bipyramidal environment of the metal ion. Within this structure, the nitrate ions form a honeycomb-like chain structure with HgII being positioned inside the combs. This work represents the first report of such geometry for a transition metal ion surrounded by symmetrically bidentate nitrate ions. The corresponding nucleoside, 1-deazapurine 2′-deoxyribonucleoside, also forms a stable 2:1 complex with HgII, as was shown by 1H NMR spectroscopy, making it a potential candidate for incorporation into nucleic acids based on metal-mediated base pairs.  相似文献   

20.
An unusual Tc(III) boron-capped imine-oxime complex has been isolated from the reaction of 99TcCl3(CH3CN)(PPh3)2, dimethyl glyoxime (DMG) and ethyl boronic acid (EtB(OH)2). A single crystal X-ray structure analysis of this molecule 99TcCl(DMG)2(BDI)BEt (BDI=butane-2, 3-dione imine-oxime) shows it to be seven coordinate: TcClC14H25N6O5B, a=9.073(2), b=23.686(5), c=19.539(6) Å; β=93.77(2)°, P21/n, Z=8. Its structure is very similar to that of previously reported Tc(III) complexes 99TcCl(dioxime)3BR, except that one dioxime ligand on the molecule has been reduced to an imineoxime.  相似文献   

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