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1.
《Journal of Coordination Chemistry》2012,65(1-3):163-172
Abstract The kinetics of the transformation of [Ru6(CO)18]2? into [Ru6C(CO)16]2? in diglyme over the temperature range 130–160°C have been determined. The results are consistent with reversible loss of a carbonyl ligand from [Ru6(CO)18]2?, followed by formation of carbon dioxide and reassociation of carbon monoxide to give the observed product. Mass spectral analysis of the evolved carbon dioxide trapped as barium carbonate supports an intramolecular pathway for the disproportionation of carbon monoxide. 相似文献
2.
Dr. Sara Sabater Dr. David Schmidt Dr. Heidi Schmidt Dr. Maximilian W. Kuntze-Fechner Dr. Thomas Zell Connie J. Isaac Dr. Nasir A. Rajabi Harry Grieve Dr. William J. M. Blackaby Dr. John P. Lowe Prof. Stuart A. Macgregor Dr. Mary F. Mahon Prof. Dr. Udo Radius Prof. Michael K. Whittlesey 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(52):13221-13234
The addition of PPh2H, PPhMeH, PPhH2, P(para-Tol)H2, PMesH2 and PH3 to the two-coordinate Ni0 N-heterocyclic carbene species [Ni(NHC)2] (NHC=IiPr2, IMe4, IEt2Me2) affords a series of mononuclear, terminal phosphido nickel complexes. Structural characterisation of nine of these compounds shows that they have unusual trans [H−Ni−PR2] or novel trans [R2P−Ni−PR2] geometries. The bis-phosphido complexes are more accessible when smaller NHCs (IMe4>IEt2Me2>IiPr2) and phosphines are employed. P−P activation of the diphosphines R2P−PR2 (R2=Ph2, PhMe) provides an alternative route to some of the [Ni(NHC)2(PR2)2] complexes. DFT calculations capture these trends with P−H bond activation proceeding from unconventional phosphine adducts in which the H substituent bridges the Ni−P bond. P−P bond activation from [Ni(NHC)2(Ph2P−PPh2)] adducts proceeds with computed barriers below 10 kcal mol−1. The ability of the [Ni(NHC)2] moiety to afford isolable terminal phosphido products reflects the stability of the Ni−NHC bond that prevents ligand dissociation and onward reaction. 相似文献
3.
《Journal of organometallic chemistry》1986,309(3):355-362
A variety of electrochemical reactions has been observed for the carbido-carbonyl clusters [Co8(CO)18C](NMe3CH2C6H5)2, [Co6(CO)15C](NMe3CH2C6H5)2, [Rh6(CO)15C](Et4N)2 and [Fe6(CO)16C](Et4N)2. The hexanuclear clusters undergo irreversible electrochemical oxidation and reduction steps, whereas the octacobalt species exhibits three electrochemically reversible one-electron steps. The relation between the redox properties and the structure of these clusters is discussed. 相似文献
4.
《Chemical physics letters》1987,135(6):525-528
The pressure shifts of the first three bands appearing in the visible spectra of [Pt3(CO)6]2−n (n = 3–5) have been measured in solution over the range 0–10 kbar. Previous electronic calculations performed on the dimer in conjunction with these results afford a possible set of assignments for the first three bands appearing in the visible spectrum for the dimer. 相似文献
5.
《Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy》1992,48(11-12):1773-1777
The complex ion [Fe(CN)6SO3]4− has been prepared in aqueous solution and as the zinc salt in the solid state. The electronic and IR spectra of the complex ion (I) have been recorded. MO calculations have been performed to understand the electronic structure of complex I. The electronic spectra of I and hexacyanoferrate(II) [HCF(II)] have been calculated and compared with the experimental results for I, HCF(II) and HCF(III). The experimental and theoretical results suggest that the oxidation state of Fe in I is + 3 and not +2 and the SO3 moiety is bonded to one of the nitrogen atoms of the cyano group. 相似文献
6.
《Polyhedron》1987,6(6):1445-1456
Reactions of [Fe2S2(CO)6]2− (3) with [Cl2FeS2MS2]2− [M = Mo (4) or W (6)] and [Cl2FeS2VS2FeCl2]3− (8) in acetonitrile-THF solutions afford the new clusters [MFe3S6(CO)6]2− (M = Mo (5) or W (7)] and [VFe6S8(CO)12]3− (9). (Et4N)2 (5) crystallizes in orthorhombic space group Pbcn with a = 15.314(7) Å, b = 16.627(6) Å, c = 29.971(13) Å, and Z = 8. Cluster 5 is formed by displacement of chloride from 4 by 3 to yield a species with the [Fe2(μ3-S)2Fe(μ2-S)2MoS2]2− core arrangement containing one Fe(II) and Mo(VI) in distorted tetrahedral sites. Similar structures are proposed for 7 and 9, with the latter containing two 3 ligands bound to the [VFe2S4]1+ core of 8. Treatment of 5 with RSSR results in oxidative decarbonylation and formation of [Mo2Fe6S8(S2)2(SR)6]4− (10) (R = p-C6H4Cl or p-C6H4Br), which consists of two [MoFe3(μ3-S)4]3+ cubane-type subclusters bridged by two μ2-η3-S22− groups. Cluster 10 was also obtained in a direct-assembly system consisting of [MoS4]2− + 3FeCl3+ S22− + 7RS− in methanol. Evidence is presented that the solid-state structure of 10 is maintained in solution. The redox change [MoFe3(μ2-S)2(μ3-S) 2S2]2− (5) → [MoFe3(μ3-S)4(S2)]1+ (10) is described as an oxidatively induced core internal conversion in which there is net Fe and S oxidation and Mo reduction. It is argued that the reduction of tetrahedral Mo(VI) to or near Mo(III), stabilized in a six-coordinate site, is a significant factor in the formation of the cubane structure. The formation of the cubane cluster [VFe3S4Cl3(DMF)3]1− from 8 and FeCl2 is similarly promoted by the reduction of tetrahedral V(V) to or near V(III). The syntheses of 5, 7, 9 and 10 illustrate the utility of 3 as a cluster precursor. 相似文献
7.
《Journal of organometallic chemistry》1991,407(2):C13-C15
The dianion [Ru10C(CO)24]2− in CH2Cl2 reacts with CO under ambient conditions to produce quantitative amounts of the species [Ru3(CO)12] and [Ru6C(CO)16]2−; the hydrido-anion [HRu10C(CO)24]− reacts similarly to form [Ru6C(CO)16]−. 相似文献
8.
Hong-Lei Xu Dr. Ivan A. Popov Nikolay V. Tkachenko Dr. Zi-Chuan Wang Prof. Dr. Alvaro Muñoz-Castro Prof. Dr. Alexander I. Boldyrev Prof. Dr. Zhong-Ming Sun 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(39):17439-17443
In this work, the largest heterometallic supertetrahedral clusters, [Zn6Ge16]4− and [Cd6Ge16]4−, were directly self-assembled through highly-charged [Ge4]4− units and transition metal cations, in which 3-center–2-electron σ bonding in Ge2Zn or Ge2Cd triangles plays a vital role in the stabilization of the whole structure. The cluster structures have an open framework with a large central cavity of diameter 4.6 Å for Zn and 5.0 Å for Cd, respectively. Time-dependent HRESI-MS spectra show that the larger clusters grow from smaller components with a single [Ge4]4− and ZnMes2 units. Calculations performed at the DFT level indicate a very large HOMO–LUMO energy gap in [M6Ge16]4− (2.22 eV), suggesting high kinetic stability that may offer opportunities in materials science. These observations offer a new strategy for the assembly of heterometallic clusters with high symmetry. 相似文献
9.
Angelo J. Amoroso Brian F. G. Johnson Jack Lewis Chi-Keung Li Catherine A. Morewood Paul R. Raithby Maria D. Vargas Wing-Tak Wong 《Journal of Cluster Science》1995,6(1):163-173
Reduction of the heptaosmium cluster [Os7(CO)21] With [Et4N][NH4) gives the cluster dianion [Os7(CO)20]2–,1, in high yield. The reaction of the dianion with [AuPR
3Cl] (R=Et or Ph) in the presence of TlPF6 forms [Os7((CO)20(AuPR
3)2] [R=Et (2a);R = Ph(2b)] in 80% yield, while the corresponding reaction with (Os(C6H6)(CH3CN)3]2+ gives [Os8(CO)20 (
6-C6H6)] (3) in reasonable yield (ca. 30%). The dianion,1, and the clusters2 and3 have been fully characterized by bout spectroscopic and crystallographic methods. The crystal structure of the [Ph4P]+ salt of1 shows that the metals in the anion adopt a capped octahedral geometry, with all twenty carbonyl ligands in terminal sites. The metal core geometry in2a is best described as a tricapped octahedron, and is based on the structure of the dianion1 with two adjacent octahedral faces capped by the Au atoms of the two AuPEt3 groups. In a similar fashion, the geometry of3 is related to that of1 with the addition of an Os(C6H6) unit capped to a triangular face, to give a bicapped octahedral framework. 相似文献
10.
M. Maeda M. Takahashi M. Takeda 《Journal of Radioanalytical and Nuclear Chemistry》1999,239(2):233-236
121Sb Mössbauer spectra of the title complexes, whose isomer shifts are intermediate between the organoantimony(III) and organoantimony(V) compounds, suggest that considerable electrons are donated from hydrido ligand and Fe(CO)4 fragments to the antimony atom. 相似文献
11.
《Journal of Coordination Chemistry》2012,65(4):550-562
Three new cyano-bridged complexes 1 [Ni(tn)2Ni(CN)4] (tn?=?1,3-diaminopropane), 2 [CuII(dipn)NiII(CN)4], and 3 [Cu(dipn)]6[Co(CN)6]4?·?4H2O (dipn?=?dipropylenetriamine) have been assembled by the templates [Ni(CN)4]2? and [Co(CN)6]3?. 1 consists of a one-dimensional linear chain–Ni(tn)2–NC–Ni(CN)2–CN–Ni(tn)2? in which the Ni(II) centers are linked by two CN groups. One 1-D zigzag chain of 2 is formed with–Ni(2)–C–N–Cu(1)–N–C–linkages. A 2D structure of 3 is formed by an alternate array of [Co(CN)6]3? and [Co][Cu6] units. For 1, there is an overall weak antiferromagnetic interaction between Ni(II) ions through the–NC–Ni–CN–bridges of the diamagnetic [Ni(CN)4]2? anions. 2 exhibits a weak antiferromagnetic exchange interaction between copper(II) ions mediated by [Ni(CN)4]2? diamagnetic bridges. Complex 3 exhibits a weak ferromagnetic interaction between nearest CuII and CuII atoms through–NC–Co–CN–bridges. 相似文献
12.
The reaction of AgNO3 with [(“Bu4N2 i-MNT)]3 in CH3CN produces a new silver cluster anion [Ag4(i-MNT)4]4? ,3, a species having a tetrahedral arrangement of silver atoms bridged by fouri-MNT ligands which has been isolated and characterized by X-ray crystallography as [Bu4N]2[(PPh3)2]2 [Ag4(i-MNT)4],4. The reaction of two or three equivalents of Ag(PPh3)2NO3 with [BzEt3N]6[Ag6(i-MNT)6] in CH3CN produces two new clusters, [BzEt3N]4[Ag8(i-MNT)6(PPh3)4],6, and [BzEt3N]3[Ag4(i-MNT)6(PPh3)6], 7, having the common structural feature of an octahedral Ag6S12 core. The octanuclear Ag8 cluster also can be synthesized from the reaction of 4 and PPh3 in CH2Ck2 and compound 5 has been structurally characterized as [Bu4N]2[(PPh3)2N]2[Ag8(i-MNT)6(PPh3)4]. The31P{1H} NMR spectrum of 6 in CD3CN at ?43° shows two sets of two doublets. The corresponding chemical shift and coupling constant of each species is 9.32 ppm (354, 408.8 Hz) and 9.45 ppm (346.7, 401.7 Hz), respectively. Pertinent crystallographic data are as follows: Compound 4 crystallizes in the orthorhombic space group Cc2a, witha=18.668(3)A,b=36.793(4) A,c=17.836(3)A, Z=4, andV= 12250(3)A3. Compound 5 crystallizes in the triclinic space group P1, witha=16.506(3)A,b=17.280(3)A,c=19.144(4) A,x=98.485(14)°, β= 105.44(2)°.y=94.63(2),Z= 1, andV = 5164(2)A3. Compound6 crystallizes in the monoclinic space group C2/m, witha= 25.341(9)A,b= 25.289(9)A,c= 15.076(7)A, β= 107.19(5)°,Z=2, and V=9230(6)A3. Compound7 crystallizes in the monoclinic space group C2/c, witha=25.872(6)A,b=21.288(4) A,c=35,928(5), β=100.98(1)°,Z-4, andV=19426(6)A3. 相似文献
13.
V. V. Sharutin A. P. Pakusina O. K. Sharutina I. V. Egorova M. A. Pushilin 《Russian Journal of Coordination Chemistry》2007,33(2):96-103
The reaction of pentaphenylantimony with mercury iodide affords the ionic complex [Ph4Sb] 2 + [Hg2I6]2?·Ph2Hg (I). The [Ph4Sb] 2 + [Hg2I6]2? (II) and [Ph4Sb] 2 + [Cd2I6]2? (III) complexes are synthesized from tetraphenylantimony iodide and mercury and cadmium iodides. The [Ph4Sb] 2 + [Hg4I10]2? complex (IV) is prepared from tetraphenylantimony 2,4-dimethylbenzenesulfonate and mercury iodide. According to the X-ray diffraction data, the Sb atom in the [Ph4Sb]+ cations of complex I has virtually ideal tetrahedral coordination (the CSbC angles are 108.09°–109.64°). In the central square fragment Hg2I2 of the [Hg2I6]2? anion, the Hg-Ibr bond lengths are 2.825 and 3.075 Å, and the terminal iodine atoms are more strongly bonded to the mercury atoms (Hg-Iterm 2.691 and 2.700 Å). The [Cd2I6]2? anion in complex III has a similar structure (the Cd-Ibridg and Cd-Iterm distances are 2.865, 2.872 and 2.723, 2.748 Å, respectively). The anions in complex IV are joined by I…Hg (3.651 Å) and I…I (4.058 Å) interactions into an infinite dimeric network. 相似文献
14.
L. Gao 《Russian Journal of Coordination Chemistry》2014,40(3):138-142
Reaction of Hg(NO3)2 with 4 equivalent KI in water afford K2[HgI4]. By using K2[HgI4] as the precursor, three new heterobimetallic compounds [Ni(N-MeIm)6][HgI4] (I), [Co(N-MeIm)6][HgI4] (II), and [Cu(N-MeIm)6][HgI4] (III) have been characterized by elemental analysis, IR spectra, and the singlecrystal X-ray crystallorgraphy analysis. Three complexes are isomorphous and crystallized in monoclinic symmetry space group P21/c. The coordination around each center metal(II) atom is octahedral with six nitrogen atoms of N-MeIm ligand. Each structure contains one tetrahedral [HgI4]2? as an anion to balance the charge of the molecular. Thermogravimetry analysis indicates these complexes have the similar departure process and cyclic voltammogram exhibits a significant pair of redox peaks. 相似文献
15.
《Journal of Coordination Chemistry》2012,65(8):705-713
A new ion-pair complex, [BrBzMeQl][Ni(mnt)2] (1) ([BrBzMeQl]+?=?1-(4′-bromobenzyl)-2-methylquinolinium; mnt2??=?maleonitriledithiolate), has been prepared and characterized. X-ray diffraction analysis shows that the Ni(mnt)2 anion and [BrBzMeQl]+ cations of 1 form completely segregated stacking columns, with the Ni?···?Ni distances alternating between 3.717 and 4.466?Å?in the Ni(mnt)2 stacking column. The variable-temperature magnetic susceptibilities of 1 have been measured over the range 75–300?K and the results reveal that the complex exhibits antiferromagnetic behavior. 相似文献
16.
Edgar König 《Theoretical chemistry accounts》1962,1(1):23-35
Zusammenfassung Die Absorptions- und Reflexionsspektren der Oktocyanokomplexe desMo(IV) undW(IV) sowie die Absorptionsspektren der Oktocyanotomplexe desMo(V) undW(V) werden mitgeteilt. Die Spektren werden unter Zugrundelegung der durch Raman- und IR-spektroskopische Untersuchungen gefordertenD
4d-Symmetrie dieser Verbindungen interpretiert. Die beobachteten Banden niedriger Intensität (log<3) werden Übergängen in einem Termsystem zugeordnet, das für die Konfigurationend
2 undd
1 und die SymmetrieD
4d berechnet worden ist. Banden hoher Intensität (log>3) werden auf Übergänge in antibindende Zustände zurückgeführt, an denen höherep-Zustände des Zentralions sowie Ligandenzustände beteiligt sind. Die erhaltenen Werte des Feldparameters stimmen mit ligandenfeldtheoretischen Erwartungen überein.
Absorption and reflection spectra of the octacyanides ofMo(IV) andW(IV) and the absorption spectra of the octacyanides ofMo(V) andW(V) are presented. The spectra are interpreted in terms of theD 4d symmetry of the compounds supported by investigations of Raman and infrared spectra. Bands of low intensity (log<3) correspond to transitions between levels obtained in the case of the configurationsd 2 andd 1 respectively, in a field ofD 4d symmetry. Bands of high intensity (log>3) are attributed to transitions into antibonding levels in which p-orbitals of the central ion and ligand orbitals participate. The values of the field parameter obtained are in accord with ligand field theory.
Résumé Les spectres d'absorption et de réflexion des complexes octocyanurés duMo(IV) et duW(IV) ainsi que les spectres d'absorption des mêmes complexes deMo(V) et de W(V) sont présentés. Les spectres sont interprétés en supposant la symétrieD 4d des molécules indiquée par des analyses des spectres Raman et infrarouges. Les bandes de faible intensité (log<3) sont attribuées à des transitions dans un système de niveaux, calculé pour les configurationsd 2 etd 1, respectivement, en symétrieD 4d. Des bandes de forte intensité (log>3) sont attribuées à des transitions vers des niveaux antiliants auxquels participent des fonctions élevéesp de l'ion central et des fonctions des groupes liés. Les valeurs obtenues pour le paramètre de champ sont en accord avec les prévisions de la théorie.相似文献
17.
18.
Roberto Della Pergola Luigi Garlaschelli Mario Manassero Mirella Sansoni Donatella Strumolo 《Journal of Cluster Science》2001,12(1):23-34
The cluster [HIr5(CO)12]2- (1) was prepared by condensation of [HIr4(CO)11]- and [Ir(CO)4]- (molar ratio 1:1) in refluxing THF, with almost quantitative yields. Its solid state structure was determined by X-ray diffraction at low temperature on the salt [PPh3CH2Ph]2[HIr5(CO)12]. The metal atoms define a trigonal bipyramidal arrangement. The hydride ligand was located indirectly as a bridge between apical and equatorial metal atoms. The phosphine-substituted cluster [HIr4(CO)10PPh3]- (2) was synthetized by CO displacement on [HIr4(CO)11]-, in THF at room temperature. This reaction is selective, with no traces of polysubstitution products. In the solid state, the hydride and the triphenylphosphine are axially bound on basal iridium atoms; the terminal hydrogen atom was directly located by X-ray analysis at a Ir–H distance of 1.57(9) Å. On the contrary, two isomers are present in THF solution, and they interconvert rapidly at room temperature, as shown by1H and 31P NMR spectra. 相似文献
19.
《Journal of Molecular Catalysis #》1992,71(3):391-398
[FeII(SPh)4]2− (1) and [FeII(SePh)4]2− (2) exhibit high catalytic activity in the oxidation of benzoin with p-benzoquinone or air and of p-substituted benzhydrol with air under mild conditions (1 atm, 25 °C). p-Substitution of benzhydrols shows a trend in the oxidation rate: 4-Cl>H>4-OMe. Furthermore, the observed isotope effect of kH/kD = 4.0 (catalyzed by [Fe(Sph)4]2− (1)) and 3.3 (catalyzed by [Fe(SePh)4]2− (2)) in the p-benzoquinone oxidation of benzoin indicates that the methine hydrogen of benzoin and benzhydrol is released as a proton in the rate-determining step. 相似文献
20.
The reaction of molybdenum hexacarbonyl with C6H5CH2OC6H4ONa and Et4NBr in CH3CN at 60 ℃ afforded the di-nuclear Mo(0) compound [Et4N]3[Mo2(CO)6(μ-OC6H4OCH2- C6H5)3] 1. 1 crystallizes in monoclinic, space group P21/c with a=15.359(2), b=18.378(3), c=24.952(2)(A), β=102.268(4)°, V=6882.3(16) (A)3, Mr=1348.34, Z=4, Dc=1.301 g/cm3, F(000)=2832 and μ= 0.424 mm-1. The final R=0.0606 and wR=0.1552 for 9396 observed reflections (Ⅰ > 2σ(Ⅰ)). 1 contains a [Mo2O3]3- core in triangular bi-pyramidal configuration and each Mo atom adopts a distorted octahedral geometry with three carbon atoms from carbonyls and three μ-O atoms from C6H5CH2OC6H4O- bridging ligands. The Mo…Mo distance is 3.30(8) (A), indicating no metalmetal bonding. A formation pathway via forming a di-molybdenum(0) di-bridging OR compound [Mo2(μ-OR)2(CO)8]2- has been figured out and the reaction of Mo(CO)6 with alkoxide has also been discussed. 相似文献