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1.
Abstract

(TTP) hafnium dichloride, 1, where TTP = meso-5,10,15,20 tetratolyl porphyrin dianion, has been synthesized and spectroscopically characterized as a precursor to 2. Hydrolysis of 1 gives (TTP) hafnium μ-dioxo dimer, 2. (TTP) vanadium oxo complex, 3, can be obtained by hydrolysis of the corresponding chloro complex. Compound 2 has been characterized by spectroscopic and single crystal X-ray diffraction analyses. [(TTP)HfO]2-toluene crystalizes in the space group C2/c, a = 31.906(6) Å, b = 16.864(3) Å, c = 19.180(4) Å, β = 117.52(3)°, V = 9152(3) Å3, dcalcd = 1.369 g/cm3, Z = 8, 6029 unique observed reflections, final R = 0.077. The Hf atom is 1.02 Å from the plane of the porphyrin ring; Hf-O bond lengths are 2.1 Å. The hafnium atoms are 3.06(1) Å from each other and the average Hf-O-Hf angle is 94°. The porphyrin rings are 5.4° from being parallel and the distance between the centers of the porphyrin rings is ~ 5.1 Å. TTPVO·mesitylene, 3, crystallizes from mesitylene in the space group P1, a = 8.365(2), b = 10.320(3), c = 14.380(5) Å, α = 91.91(3), β = 91.44(3), γ = 108.26(2)°, V = 1177.2(6) Å3, dcalcd = 1.27 g/cm3, Z = 1, 1851 observed unique reflections, final R = 0.069. The average V - N distance = 2.016 Å. The coordination geometry around the vanadium is distorted C4V. The V = O group is disordered about the center of inversion. The vanadium atom resides 0.57 Å above the plane of the nitrogens. The (ring center) -V = O angle is 165.9° while the V = O vector is essentially colinear with the vector normal to the plane of nitrogens.  相似文献   

2.
The local structure of the double perovskite (Sr2‐xCax)FeMoO6 (0 ≤ × ≤ 2.0) and Sr2CrMO6 (M = Mo, W) systems have been probed by extended X‐ray absorption fine structure (EXAFS) spectroscopy at the Fe and Cr K‐edges. We found Fe‐O (ave) distance apparently decreases from 1.999 Å (x = 0) to 1.991 Å (x = 1.0) in (Sr2‐xCax)FeMoO6 (tetragonal structure). When x is increased further from 1.5 to 2.0, the Fe‐O bond distance decreased from 2.034 Å to 2.012 Å (monoclinic structure). In addition, Cr‐O, Sr‐Cr, and Cr‐Mo bond distances in Sr2CrWO6 are all slightly larger than the bond distances of Sr2CrMoO6, which is due to the ionic radius of the W5+ (0.62 Å) which is larger than the ionic radius of Mo5+ (0.61 Å). The results are consistent with our XRD refinements data.  相似文献   

3.
A novel ZnII complex of the saccharinate ligand (sac) with tris‐hydroxymethylaminomethane (tham) was synthesized and characterized by elemental analysis, FT‐IR spectroscopy, simultaneous TG and DTA techniques, and X‐ray diffraction. The complex, [Zn(sac)(tham)2](sac), crystallizes in monoclinic system with space group P21/c [a = 7.55954(3) Å, b = 13.0532(6) Å, c = 27.7777(10) Å, β = 100.539(3)°, Z = 4]. The ZnII ion has a distorted octahedral coordination. The tham ligand has chemically different functions in the structure, acting as both bidentate and tridentate ligands. There are also sac moieties to act as N‐bonded ligand and as a counter anion. The molecular packing of the complex is provided by moderate hydrogen bonds as well as π···π interactions between the sac moieties. The IR spectra and the thermal decomposition of the complex are also discussed.  相似文献   

4.
Abstract

The crystal structure of tetrakis(N,N′-dimethylthiourea)nickel(II) bromide dihydrate has been determined by three-dimensional x-ray diffraction from 1916 counter-data reflections collected at room temperature.

The structure consists of Ni[SC(NH)2(CH3)2]2+ 4 molecular ions, Br? ions and waters of hydration. The nickel is located on a center of symmetry and is coordinated to four sulfur atoms in a square planar configuration. The waters of hydration and the bromide ions are involved in hydrogen bonding to the N,N′-dimethylthiourea (dmtu) groups. The orientation of the dmtu groups is such that two bond through the sulfur sp2 orbital and the others bond through the π-orbitals of the dmtu group. The Ni-S distances are 2.204 ± 0.002 Å and 2.230 ± 0.002 Å, and the Ni-S-C angles are 106.2 ± 0.2Å and 110.3 ± 0.3°. The dmtu groups are planar except for methyl hydrogens.

The crystals are monoclinic, P21/a with a = 13.424 ± 0.002 Å, b = 12.321 ± 0.005 Å, c = 8.460 ± 0.008 Å β = 107.07 ± 0.05°, ρ0 = 1.67 g cm?3, ρc = 1.66 g cm?3 and Z = 2. The structure was refined by full-matrix least-squares to a conventional R of 0.0466.  相似文献   

5.
The title compound is an ethanol‐solvated salt, C16H38N42+·2C11H7O2·2C2H6O, in which the cation lies across a centre of inversion in P21/c. The ions are linked by N—H⃛O hydrogen bonds [H⃛O = 1.70 and 2.30 Å, N⃛O = 2.624 (2) and 3.136 (2) Å, and N—H⃛O = 178 and 151°], and the ethanol mol­ecule is linked to the anion by an O—H⃛O hydrogen bond [H⃛O = 1.90 Å, O⃛O = 2.728 (2) Å and O—H⃛O = 171°], to form a centrosymmetric five‐component aggregate. C—H⃛O hydrogen bonds and aromatic π–π‐stacking interactions are absent, but the aggregates are linked into sheets by a single C—H⃛π(arene) hydrogen bond.  相似文献   

6.
Five‐coordinate Cr(N)(salen) {salen is 2,2′‐[ethane‐1,2‐diylbis(nitrilomethylidyne)]diphenolate} reacts with [RhCl(COD)]2 (COD is 1,5‐cyclooctadiene) to yield the heterobimetallic nitride‐bridged title compound, namely chlorido‐2κCl‐[2(η4)‐1,5‐cyclooctadiene]{2,2′‐[ethane‐1,2‐diylbis(nitrilomethylidyne)]diphenolato‐1κ4O,N,N′,O′}‐μ‐nitrido‐1:2κ2N:N‐chromium(V)rhodium(I), [CrRh(C16H14N2O2)ClN(C8H12)]. The Cr—N bond of 1.5936 (14) Å is elongated by only 0.035 Å compared to the terminal Cr—N bond in the precursor. The nitride bridge is close to being linear [173.03 (9)°] and the Rh—N bond of 1.9594 (14) Å is very short for a monodentate nitrogen‐donor ligand, indicating significant π‐acceptor character of the Cr[triple‐bond]N group.  相似文献   

7.
The title compound has been prepared by reaction of (C5H5)2Cr with oxindole (indole with CO in place of CH2 at the 2-position). Red single crystals belong to space group P21/c with a = 10.107(4) Å, b = 22.496(7) Å, c = 9.210(3) Å, β = 93.26(3)°, V = 2091(2), and Z = 2. The centrosymmetric molecule has a CrCr distance of 2.495(4) Å. The mean CrO and CrN distances for the bonds to bridging oxindolate anions are 2.024(7) and 2.065(8) Å, respectively. There is an oxindole molecule bound at each end with a CrO axial bond of length 2.341(8) Å and a hydrogen bond from the oxindole NH group to an equatorial oxygen atom of length 2.83(1) Å. The significance of this compound with respect to CrCr bonding is discussed.  相似文献   

8.
While six‐coordinate iron(III) porphyrin complexes with pyridine N‐oxides as axial ligands have been studied as they exhibit rare spin‐crossover behavior, studies of five‐coordinate iron(III) porphyrin complexes including neutral axial ligands are rare. A five‐coordinate pyridine N‐oxide–5,10,15,20‐tetraphenylporphyrinate–iron(III) complex, namely (pyridine N‐oxide‐κO)(5,10,15,20‐tetraphenylporphinato‐κ4N,N′,N′′,N′′′)iron(III) hexafluoroantimonate(V) dichloromethane disolvate, [Fe(C44H28N4)(C5H5NO)][SbF6]·2CH2Cl2, was isolated and its crystal structure determined in the space group P. The porphyrin core is moderately saddled and the Fe—O—N bond angle is 122.08 (13)°. The average Fe—N bond length is 2.03 Å and the Fe—ONC5H5 bond length is 1.9500 (14) Å. This complex provides a rare example of a five‐coordinate iron(III) porphyrin complex that is coordinated to a neutral organic ligand through an O‐monodentate binding mode.  相似文献   

9.
By heating the mixture of solutions of (CpCrSCMe3)2S (I) in benzene and [CpNi(CO)]2 in pentane followed by chromatography on alumina, dark cherry-red needles of the heteronuclear cluster (Cp4Cr2Ni2)(μ3-S)24-S) (II) were obtained, whose structure was established on the basis of a complete X-ray analysis. The crystals are rhombic, spatial group Pbca; a = 12.07(1), b = 18.50(2), c = 17.36(1) Å, Z = 8. The metallic skeleton of II has the “butterfly” or “metal-chain” structure with a direct CrCr bond (2.62(1) Å) and inequivalent CrNi bonds, 2.86(1) and 2.64(1) Å, while the Ni·Ni distance is nonbonding (4.34(1) Å). The NiCr2 triangle planes produce a dihedral angle of 127°. The two μ3-bridged sulfur atoms locate under these triangles whereas the third sulfur atom is μ4-bridging coordinating all four metal atoms in the cluster with mean NiS and CrS distances of 2.29(1) and 2.25(1) Å, respectively. The Ni2S3 group is planar and almost perpendicular to the CrCr axis. Complex II is anti-ferromagnetic and its exchange parameter — 2J (418 cm-1) is close to that found for the initial binuclear complex I (— 2J = 430 cm-1 with a CrCr bond length of 2.689(8) Å). The role of the Ni coordination number in the generation of II is discussed.  相似文献   

10.
Relativistic density functional calculations have been carried out for the group VI transition metal carbonyls M(CO)5L (M=Cr, Mo, W; L=OH2, NH3, PH3, PMe3, N2, CO, OC (isocarbonyl), CS, CH2, CF2, CCl2, NO+). The optimized molecular structures and M(SINGLE BOND)L bond dissociation energies, as well as the metal–carbonyl bond energy of the trans CO group, have been calculated. Besides the marked dependence of the trans M(SINGLE BOND)CO bond length on the type of ligand L, such an effect on the that bond energy is also observed. For the chromium compounds, the trans Cr(SINGLE BOND)CO bond length varies from 184 to 199 pm and its bond energy from 242 to 150 kJ/mol. For the molybdenum compounds, the range is 197 to 216 pm and 253 to 128 kJ/mol and, for tungsten, 198 to 214 pm and 293 to 159 kJ/mol. The observed trends can be explained with the π acceptor strength of the L ligand. © 1997 John Wiley & Sons, Inc. J Comput Chem 18 : 1985–1992, 1997  相似文献   

11.
The 31P{1H}-NMR characteristics of the complexes [HgX2( 1 )] and [HgX2-(PPh2Bz)2] (X = NO3, Cl, Br, I, SCN, CN) and the solid state structures of the complexes [HgCl2( 1 )] and [HgI2( 1 )] ( 1 = 2,11-bis (diphenylphosphinomethyl)benzo-[c]phenanthrene) have been determined. The 1J(199Hg, 31P) values increase in the order CN < I < SCN < Br < Cl < NO3. The two molecular structures show a distorted tetrahedral geometry about mercury. Pertinent bond lengths and bond angles from the X-ray analysis are as follows: Hg? P = 2.485(7) Å and 2.509 (8) Å, Hg? Cl = 2.525 (8) Å and 2.505 (10) Å, P? Hg? P = 125.6(3)°, Cl? Hg? Cl = 97.0(3)° for [HgCl2( 1 )] and Hg? P = 2.491 (10) Å and 2.500(11) Å, Hg? I = 2.858(5) Å and 2.832(3) Å, P? Hg? P = 146.0(4)°, I? Hg? I = 116.9(1)° for [HgI2( 1 )]. The equation, derived previously, relating 1J(199Hg, 31P) and the angles P? Hg? P and X? Hg? X is shown to be valid for 1 .  相似文献   

12.
Abstract

The crystal and molecular structure of N-(O,O-diisopropyl phosphoryl)-trans-4-hydroxy-D,L-proline has been determined by X-ray diffraction analysis and is compared with proline or hydroxyproline residue in a peptide chain described in the literature. The compound crystallized in orthorhombic system with space group P212121, a=6.934(2), b=8.694(3), c=26.727(7) Å, V=1611.3(8) Å3, Z=4, Dx=1.22 g/cm3. The structure was solved by direct method and refined by anisotropic least squares to a discrepancy index R=0.072. In the compound, the nitrogen atom is trigonal and its remaining 2p orbital is conjugated with the P?Oπ system; the conformation of the phosphorimidate function is favoured by the trans orientation of the P=O bond with respect to the N-C4 bond. In the pyrrolidine ring moeity, the C2-C1-N-C4 atoms are nearly copolnar and the C3 atom is out of the plane by about 0.47 Å.  相似文献   

13.
Wentong Chen 《中国化学》2012,30(2):273-276
A novel zinc porphyrin, {[ZnTCPP(EtOH)][Zn(en)]2}n(EtOH)2n ( 1 ) (TCPP=meso‐tetra(4‐carboxyphenyl)‐porphyrin; EtOH=ethanol; en=ethylenediamine) was obtained via a hydrothermal reaction and characterized by single‐crystal X‐ray diffraction. Complex 1 crystallizes in the space group C2/c of the monoclinic system with eight formula units in a cell: a=32.465(4) Å, b=10.527(3) Å, c=31.845(3) Å, β=95.524(6) °, V=10832(4) Å3, C58H57N8O11Zn3, Mr=1238.23, Dc=1.518 g/cm3, S=1.005, µ(Mo Kα) =1.388 mm?1, F(000) =5112, R=0.0650 and wR=0.1574. Complex 1 features a novel 2‐D layered motif. The spectral data of UV‐vis, FT‐IR and fluorescence are reported.  相似文献   

14.
The crystal and molecular structure of methylbenzoatechromium dicarbonyl thiocarbonyl has been determined by a single-crystal X-ray study. The compound crystallizes with two molecules in a unit cell of symmetry P1, with the following parameters: triclinic system, a = 7.108(3), b = 10.340(4), c = 8.523(3) Å; α = 89.75(6), β = 95.89(4), γ = 105.50(4)°; V = 601 Å3; dm = 1.57 ± 0.05, dc = 1.56. The structure has been refined to R and R″ values of 0.030 and 0.038 respectively, for 1963 independent reflections. The main feature of the molecule is the Cs symmetry of the Cr(CO)2CS group with a CrC(S) bond length of 1.792(2) Å, shorter than the CrC(O) bond length, mean: 1.849(3) Å.  相似文献   

15.
1H- and 13C-NMR. data are reported for the complexes [Pt (1) L] and [Pt (2) L]; 1 = OC6H4CH ? NCH2CH2O, 2 = OC6H4CH ? NC6H4O; L = PR3, AsR3, C ? N (cyclohexyl), DMSO, pyridine, secondary amine. The molecular structures of [Pt (2) (NHEt2)] (I) and [Pt (2) (PPh3)] (II) have been determined by X-ray analysis. Relevant bond distances for I: Pt-N (amine) = 2.076 Å, Pt-N (imine) = 2.017 Å, Pt-O = 1.992 Å and 2.002 Å; for II: Pt-P = 2.248 Å, Pt-N = 2.064 Å, Pt-O = 1.964 and 2.005 Å. Both the solid and solution state data are interpreted in terms of differences in the trans influence of the ligand L. The question of metal-ligand d-p π back bonding to the imine is discussed.  相似文献   

16.
Ethylenediamine (en) solutions of [P7M(CO)3]3– (M = Cr, W) react with weak acids to give [HP7M(CO)3]2– ions where M = Cr ( 4 a ) and W ( 4 b ) in high yields. Competition studies with known acids revealed a pKa range for 4 b in DMSO of 17.9 to 22.6. The [P7M(CO)3]3– complexes also react with one-half equivalent of I2 to give 4 through an oxidation/hydrogen atom abstraction process. Labeling studies show that the abstracted hydrogen originates from the [K(2,2,2-crypt)]+ ions or from the solvent (DMSO-d6) in the absence of [K(2,2,2-crypt)]+ or other good hydrogen atom donors. In the solid state, the ions have no crystallographic symmetry but in solution they show virtual Cs symmetry (31P NMR spectroscopy) due to an intramolecular wagging process. Crystallographic data for [K(2,2,2-crypt)]2[HP7W(CO)3]: triclinic, P 1, a = 10.9709(8) Å, b = 13.9116(10) Å, c = 19.6400(14) Å, α = 92.435(6)°, β = 93.856(6)°, γ = 108.413(6)°, V = 2831.2(4) Å3, Z = 2, R(F) = 7.65%, R(wF2) = 14.17% for all 7400 reflections. For [K(2,2,2-crypt)]2[HP7Cr(CO)3]: triclinic, P 1, a = 12.000(3) Å, b = 14.795(3) Å, c = 17.421(4) Å, α = 93.01(2)°, β = 93.79(2)°, γ = 110.72(2)°, V = 2877(2) Å3, Z = 2.  相似文献   

17.
The title compound (Mr = 373) crystalizes in the othorhombic space group P bna with a = 10.410(2), b = 11.658(4), c = 23.108(3) Å, V = 2804.4 Å Z = 8. The single crystal intensity data were collected using MoK∞ radiation (λ = 0.7093Å) at room temperature. The crystal and molecular structure was solved with the final agreement index R = 0.039 for 1046 observed reflections. The bond lengths N(1)- C(7) and C(7)-C(8) of the title compound are slightly longer than those of 3-substituted sydnone derivatives. This may be attributed to the steric effect arising from the interaction of the phenyl ring and the 4-substituent with the neighboring atoms of sydnone ring. Both the title compound and 4-acetyl-3-(p-tolyl)sydnone have smaller dihedral angles between the sydnone ring and the plane of the sp2 orbital of the double bond of the 4-substituent and both have shorter C(7)-C(9) bond lengths than those of other similar sydnone derivatives.  相似文献   

18.
In the title compound, C13H16N22+·2C2H4O5P, the cation lies across a twofold rotation axis in space group Fdd2. The anions are linked into molecular ladders by two O—H⃛O hydrogen bonds [H⃛O = 1.73 and 1.77 Å, O⃛O = 2.538 (2) and 2.598 (3) Å, and O—H⃛O = 160 and 170°], these ladders are linked into sheets by a single type of N—H⃛O hydrogen bond [H⃛O = 1.75 Å, N⃛O = 2.624 (3) Å and N—H⃛O = 171°] and the sheets are linked into a three‐dimensional framework by a single type of C—H⃛O hydrogen bond [H⃛O = 2.48 Å, C⃛O = 3.419 (4) Å and C—H⃛O = 167°].  相似文献   

19.
Three new oxo‐centered trinuclear mixed‐bridged carboxylate complexes with terminal unsaturated ligands ([M2M′(μ3‐O)(μ‐O2C3H3)5(μ‐O4C6H7)(O2C3H3) (H2O)2]·2H2O [M = Fe, M′ = Fe ( 1 ); M = Fe, M′ = Cr ( 2 ); M = Cr, M′ = Fe ( 3 )]) have been synthesized and characterized by means of elemental analyses, IR spectra and crystal structure analyses. The compounds crystallize isotypically in the orthorhombic space group type Pbcn with a = 24.622(3) Å, b = 16.304(2) Å, c = 17.491(2) Å, V = 7021.5(15) Å3 ( 1 ), a = 24.708(5) Å, b = 16.290(2) Å, c = 17.394(2) Å, V = 7001.0(18) Å3 ( 2 ), a = 24.611(4) Å, b = 16.300(3) Å, c = 17.359(3) Å, V = 6964(2) Å3 ( 3 ), and Z = 8. The infrared spectra show resolved bands arising from νasym(OCO) and νsym(OCO) vibrations of monodentate and bridging carboxylate ligands along with those of νasym(M2M′O) vibrations in the complexes.  相似文献   

20.
The complex cis‐[RuCl(DMSO)(phen)2]BPh4, where DMSO is dimethylsulfoxide and phen is 1, 10‐phenanthroline, crystallizes in the monoclinic space group P21/c with a = 19.505(4), b = 10.045(2), c = 21.199(4) Å, β = 90.137(4)°, V = 4153(2) Å3, Z = 4, Dcalc = 1.430 g cm—3. The ruthenium coordination geometry is that of a slightly distorted octahedron with a cis‐RuN4ClS arrangement of the ligand donor atoms. The Ru—Cl distance is 2.421(1) Å and the Ru—S distance 2.250(2) Å. The four Ru—N distances are 2.057(6), 2.066(4), 2.073(4), and 2.086(4) Å with the Ru—N bond trans to Cl the second shortest and the Ru—N bond trans to S the longest one.  相似文献   

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