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1.
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
2.
Jessica Chuang 《Inorganica chimica acta》2008,361(8):2357-2364
Hydrothermal chemistry was used to prepare the bimetallic organic-inorganic hybrid oxide [Cu(I)Cu(II)2(trz)2Mo4O13(OH)] · 6H2O (1 · 6H2O). The structure consists of chains linked through into a three-dimensional framework. The structures of the simple metal-triazole phases [MoO3(Htrz)0.5] (2) and [Cu(trz)] (3) are also reported. Compound 2 is two-dimensional, constructed from corner-sharing {MoO5N} octahedra. Compound 3 consists of {Cu(trz)}n chains linked through weak Cu?Cu contacts into a virtual layer. 相似文献
3.
Reactions of dichlorodioxobis(triphenylphosphine oxide)molybdenum(VI) complexes with ammonium/sodium salts of O,O-dialkyl(alkylene) and diphenyl dithiophosphoric acids in 1:1 molar ratio in dichloromethane solution yield dioxomolybdenum complexes of the types, MoO2Cl[S2P(OR)2] · OPPh3 (R=Me, Et, i-Pr, Ph) and MoO2Cl[S2] · OPPh3. (G=-CH2CMe2CH2O-, -OCMe2CMe2O-). These newly synthesized compounds were characterized by IR, UV-visible and 1H NMR spectroscopy and elemental analysis. The molecular structure of MoO2Cl2(OSMe2)2 was determined by single-crystal X-ray diffraction. MoO2Cl2(OSMe2)2 crystallizes as orthorhombic in the space group Pbca with cell parameters a=13.7235(3) Å, b=12.2429(2) Å, c=14.3356(3) Å, V=2408.60(8) Å−3, Z=8, R=0.0221, Rw=0.0519. There are two cis oxo ligands, two cis dimethylsulphoxide moieties and two trans chlorine atoms in a distorted octahedral environment around molybdenum. 相似文献
4.
The character and dynamics of low-lying electronic excited states of the complexes fac-[Re(Cl)(CO)3(papy)2] and fac-[Re(papy)(CO)3(bpy)]+ (papy = trans-4-phenylazopyridine) were investigated using stationary (UV-Vis absorption, resonance Raman) and ultrafast time-resolved (visible, IR absorption) spectroscopic methods. Excitation of [Re(Cl)(CO)3(papy)2] at 400 nm is directed to 1ππ∗(papy) and Re → papy 1MLCT excited states. Ultrafast (?1.4 ps) intersystem crossing (ISC) to 3nπ∗(papy) follows. Excitation of [Re(papy)(CO)3(bpy)]+ is directed to 1ππ∗(papy), 1MLCT(papy) and 1MLCT(bpy). The states 3nπ∗(papy) and 3MLCT(bpy) are then populated simultaneously in less then 0.8 ps. The 3MLCT(bpy) state decays to 3nπ∗(papy) with a 3 ps time constant. 3nπ∗(papy) is the lowest excited state for both complexes. It undergoes vibrational cooling and partial rotation around the -NN- bond, to form an intermediate with a nonplanar papy ligand in less than 40 ps. This species then undergoes ISC to the ground state potential energy surface, on which the trans and cis isomers are formed by reverse and forward intraligand papy rotation, respectively. This process occurs with a time constant of 120 and 100 ps for [Re(Cl)(CO)3(papy)2] and [Re(papy)(CO)3(bpy)]+, respectively. It is concluded that coordination of papy to the Re center accelerates the ISC, switching the photochemistry from singlet to triplet excited states. Comparison with analogous 4-styrylpyridine complexes (M. Busby, P. Matousek, M. Towrie, A. Vl?ek Jr., J. Phys. Chem. A 109 (2005) 3000) reveals similarities of the decay mechanism of excited states of Re complexes with ligands containing -NN- and -CC- bonds. Both involve sub-picosecond ISC to triplets, partial rotation around the double bond and slower ISC to the trans or cis ground state. This process is about 200 times faster for the -NN- bonded papy ligand. The intramolecular energy transfer from the 3MLCT-excited ∗Re(CO)3(bpy) chromophore to the intraligand state of the axial ligand occurs for both L = stpy and papy with a comparable rate of a few ps. 相似文献
5.
Phosphonium zwitterions of a known type were obtained in high yield via a 1:1 reaction of p-benzoquinone or methoxy-p-benzoquinone with the tertiary phosphines R3P [R = (CH2)3OH, Ph, Et, Me] and Ph2MeP, in acetone or benzene at room temperature. In all cases, attack of the P-atom occurs at a C-atom rather than at an O-atom. The products were characterized to various degrees by elemental analysis, 31P{1H}, 1H and 13C NMR spectroscopies, and mass spectrometry, and two of the zwitterions, the new [HO(CH2)3]3P+C6H2(O−)(OH)(MeO) and the known Ph3P+C6H3(O−)(OH), were structurally characterized by X-ray analysis. The PEt3 reaction also produces small amounts of the ‘dimeric’, μ-oxo co-product Et3P+C6H2(O−)(OH)-O-C6H3(O−)P+Et3 that is tentatively characterized by 1D- and 2D-NMR data. 2,5-Di-tert-butyl- and 2,3,5,6-tetramethyl-p-benzoquinone do not react with [HO(CH2)3]3P under the conditions noted above. Heating D2O solutions of the water-soluble zwitterions R3P+C6H3(O−)(OH) [R = (CH2)3OH, Et] at 90 °C for 72 h leads to complete H/D exchange of the H-atom in the position ortho to the phosphonium center. 相似文献
6.
Reaction of HSi(OEt)3 with IrCl(CO)(PPh3)2 (5:1 molar ratio) at room temperature for 1 h gives IrCl(H){Si(OEt)3}(CO)(PPh3)2 (1), which is observed by the 1H and 31P{1H} NMR spectra of the reaction mixture. The same reaction, but in 20:1 molar ratio at 50 °C for 24 h produces IrCl(H)2(CO)(PPh3)2 (2) rather than the expected product Ir(H)2{Si(OEt)3}(CO)(PPh3)2 (3) that was previously reported to be formed by this reaction. Accompanying formation of Si(OEt)4, (EtO)3SiOSi(OEt)3, and (EtO)2HSiOSi(OEt)3 is observed. On the other hand, trialkylhydrosilane HSiEt3 reacts with IrCl(CO)(PPh3)2 (10:1 molar ratio) at 80 °C for 84 h to give Ir(H)2(SiEt3)(CO)(PPh3)2 (4) in a high yield, accompanying with a release of ClSiEt3. 相似文献
7.
New mixed metal complexes SrCu2(O2CR)3(bdmap)3 (R = CF3 (1a), CH3 (1b)) and a new dinuclear bismuth complex Bi2(O2CCH3)4(bdmap)2(H2O) (2) have been synthesized. Their crystal structures have been determined by single-crystal X-ray diffraction analyses. Thermal decomposition behaviors of these complexes have been examined by TGA and X-ray powder diffraction analyses. While compound 1a decomposes to SrF2 and CuO at about 380°C, compound 1b decomposes to the corresponding oxides above 800°C. Compound 2 decomposes cleanly to Bi2O3 at 330°C. The magnetism of 1a was examined by the measurement of susceptibility from 5–300 K. Theoretical fitting for the susceptibility data revealed that 1a is an antiferromagnetically coupled system with g = 2.012(7), −2J = 34.0(8) cm−1. Crystal data for 1a: C27H51N6O9F9Cu2Sr/THF, monoclinic space group P21/m, A = 10.708(6), B = 15.20(1), C = 15.404(7) Å, β = 107.94(4)°, V = 2386(2) Å3, Z = 2; for 1b: C27H60N6O9Cu2Sr/THF, orthorhombic space group Pbcn, A = 19.164(9), B = 26.829(8), C = 17.240(9) Å, V = 8864(5) Å3, Z = 8; for 2: C22H48O11N4Bi2, monoclinic space group P21/c, A = 17.614(9), B = 10.741(3), C = 18.910(7) Å, β = 109.99(3)°, V = 3362(2) Å3, Z = 4. 相似文献
8.
Ryan Johnson 《Inorganica chimica acta》2007,360(10):3414-3423
Mo(CO)4(LL) complexes, where LL = polypyridyl ligands such as 2,2′-bipyridine and 1,10-phenanthroline, undergo quasi-reversible, one-electron oxidations in methylene chloride yielding the corresponding radical cations, [Mo(CO)4(LL)]+. These electrogenerated species undergo rapid ligand substitution in the presence of acetonitrile, yielding [Mo(CO)3(LL)(CH3CN)]+; rate constants for these substitutions were measured using chronocoulometry and were found to be influenced by the steric and electronic properties of the polypyridyl ligands. [Mo(CO)3(LL)(CH3CN)]+ radical cations, which could also be generated by reversible oxidation of Mo(CO)3(LL)(CH3CN) in acetonitrile, can be irreversibly oxidized yielding [Mo(CO)3(LL)(CH3CN)2]2+ after coordination by an additional acetonitrile. Infrared spectroelectrochemical experiments indicate the radical cations undergo ligand-induced net disproportionations that follow first-order kinetics in acetonitrile, ultimately yielding the corresponding Mo(CO)4(LL) and [Mo(CO)2(LL)(CH3CN)3]2+ species. Rate constants for the net disproportionation of [Mo(CO)3(LL)(CH3CN)]+ and the carbonyl substitution reaction of [Mo(CO)3(LL)(CH3CN)2]2+ were measured. Thin-layer bulk oxidation studies also provided infrared characterization data of [Mo(CO)4(ncp)]+ (ncp = neocuproine), [Mo(CO)3(LL)(CH3CN)]+, [Mo(CO)3(LL)(CH3CN)2]2+ and [Mo(CO)2(LL)(CH3CN)3]2+ complexes. 相似文献
9.
Daniela Belli Dell''Amico Daniele Boschi Fausto Calderazzo Luca Labella Fabio Marchetti 《Inorganica chimica acta》2002,330(1):149-154
Anhydrous Zn(O3SCF3)2 and Zn(O2CCX3)2, X=F, Cl, Br were obtained in substantially quantitative yields from ZnO (or ZnEt2 in the case of the bromide derivative) and a mixture of the corresponding acid and anhydride in heptane as medium. The reactions are rapid and moderately exothermic. Recrystallization of the triflate and trifluoroacetate complexes from dimethoxyethane (DME) produced single crystals of Zn(O3SCF3)2(DME)2 (1) and [Zn(O2CCF3)2(DME)]n (2) suitable for X-ray diffraction studies. In both compounds zinc is hexacoordinated with a pseudo-octahedral geometry. Compound 1 is constituted by mononuclear molecules with terminal monodentate O3SCF3 ligands in trans position. A polynuclear chain structure was found for 2 with zinc atoms joined alternatively by triple and single carboxylato bridges, and with bidentate terminal DME. 相似文献
10.
Anna V. Vologzhanina Larisa B. Serezhkina Viktor N. Serezhkin 《Inorganica chimica acta》2009,362(14):4921-7078
The reaction of uranyl oxalate trihydrate with guanidinium acetate at room temperature in water yields known uranyl complex with composition (CN3H6)2[UO2(C2O4)2(H2O)]·H2O as a first phase and a novel complex (CN3H6)5[(UO2)3O(OH)2(CH3COO)(C2O4)3] as a second. The second phase was investigated by means of IR spectroscopy and X-ray diffraction. The trinuclear discrete complex contains two symmetrically independent uranyl ions with a pentagonal bipyramid structure and has a nonplanar geometry. The distortion of its equatorial plane is caused by substitution of a monodentate bridge hydroxide anion by a bidentate bridge acetate-anion. The acidic ligands found in the complex are usually in competition for a place in coordination sphere of an uranyl ion, thus peculiarities of the complex formation are discussed in terms of ‘crystallochemical analysis’. 相似文献
11.
Pavel A. Abramov Rita Hernandez-Molina Alexander V. Virovets Pedro Gili Vladimir P. Fedin 《Inorganica chimica acta》2010,363(13):3330-3337
Reaction of [Mo2O2(μ-S)2(H2O)6]2+ with Mo(CO)6 or metallic Mo under hydrothermal conditions (140 °C, 4 M HCl) gives oxido-sulfido cluster aqua complex [Mo3(μ3-S)(μ-O)2(μ-S)(H2O)9]4+ (1). Similarly, [W3(μ3-S)(μ-O)2(μ-S)(H2O)9]4+ (2) is obtained from [W2O2(μ-S)2(H2O)6]2+ and W(CO)6. While reaction of [Mo2O2(μ-S)2(H2O)6]2+ with W(CO)6 mainly proceeds as simple reduction to give 1, [W2O2(μ-S)2(H2O)6]2+ with Mo(CO)6 produces new mixed-metal cluster [W2Mo(μ3-S)(μ-O)2(μ-S)(H2O)9]4+ (3) as main product. From solutions of 1 in HCl supramolecular adduct with cucurbit[6]uril (CB[6]) {[Mo3O2S2(H2O)6Cl3]2CB[6]}Cl2⋅18H2O (4) was isolated and structurally characterized. The aqua complexes were converted into acetylacetonates [M3O2S2(acac)3(py)3]PF6 (M3 = Mo3, W3, W2Mo; 5a-c), which were characterized by X-ray single crystal analysis, electrospray ionization mass spectrometry and 1H NMR spectroscopy. Crystal structure of (H5O2)(Me4N)4[W3(μ3-S)(μ2-S)(μ2-O)2(NCS)9] (6), obtained from 2, is also reported. 相似文献
12.
13.
Rui-Qin Fang 《Inorganica chimica acta》2006,359(7):2023-2028
Hydrothermal reaction of molybdenum oxide and copper(II) source in the presence of 4,4′-bipyridine (4,4′-bpy) afforded three-dimensional covalent framework [CuII(4,4′-bpy)(MoO4)] (1), while reaction with 1,4-diazoniabicyclo[2,2,2]octane (DABCO) in place of 4,4′-bpy and addition of metal molybdenum resulted in one-dimensional chain-like compound . The copper in 1 is divalent and approximately shows trigonal bipyramidal geometry, while in 2 is monovalent and approximately shows T-shaped geometry. The structure of 1 has a three-dimensional pillar-layered framework constructed from bimetallic {CuMoO4} layers bridged by bifunctional ligand 4,4′-bpy. Interestingly, the {CuMoO4} layer in 1 consists of 16-membered {Cu4Mo4O8} rings and 8-membered {Cu2Mo2O4} rings, different from other reported {CuMoO4} layers. The structure of 2 consists a one-dimensional chain that is attached by peripheral {Cu(HDABCO)}2+ units. The chain is constructed from octamolybdates through common corners. 相似文献
14.
Eric Burkholder 《Inorganica chimica acta》2004,357(1):301-304
The hydrothermal reaction of MoO3, [Cu(CH3CO2)2] · H2O, 2,2′:6′,2″-terpyridine (terpy), H2O3AsC6H5, H2O and H2SO4 yields aqua colored crystals of [{Cu(terpy)}2Mo12O34(O3AsC6H5)4] · 2.25H2O (1 · 2.25H2O). The two-dimensional structure of 1 is constructed from {Mo12O34(O3AsC6H5)4}4− clusters linked through {Cu(terpy)}2+ subunits. Each Cu(II) site exhibits {CuN3O2} coordination geometry and links two adjacent clusters. In turn, each cluster is associated with four Cu(II) sites through {MoO · Cu} interactions. 相似文献
15.
Stefanus OttoAndreas Roodt 《Inorganica chimica acta》2002,331(1):199-207
The crystal structures of the four-coordinate trans-[Rh(Cl)(CO)(SbPh3)2] (1) and the five-coordinate trans-[Rh(Cl)(CO)(SbPh3)3] (2) are reported, as well as the unexpected oxidative addition product, trans-[Rh(I)2(CH3)(CO)(SbPh3)2] (3), obtained from the reaction of 2 with CH3I. The formation constants of the five-coordinate complex were determined in dichloromethane, benzene, diethyl ether, acetone and ethyl acetate as 163±8, 363±10, 744±34, 1043±95 and 1261±96 M−1, respectively. While coordinating solvents facilitate the formation of the five-coordinate complex, the four-coordinate complex could be obtained from diethyl ether due to the favorable low crystallization energy. The tendency of stibine ligands to form five-coordinate rhodium(I) complexes is attributed mainly to electron deficient metal centers in these systems, with smaller contributions by the steric effects. The average effective cone angle for the SbPh3 ligand in the three crystallographic studies was determined as 139° with individual values ranging from 133 to 145°. 相似文献
16.
Marie-Cecile RosenblatRichard A. Henderson 《Inorganica chimica acta》2002,331(1):270-278
The kinetics of the reactions between anhydrous HCl and trans-[MoL(CNPh)(Ph2PCH2CH2PPh2)2] (L=CO, N2 or H2) have been studied in thf at 25.0 °C. When L=CO, the product is [MoH(CO)(CNPh)(Ph2PCH2CH2PPh2)2]+, and when L=H2 or N2 the product is trans-[MoCl(CNHPh)(Ph2PCH2CH2PPh2)2]. Using stopped-flow spectrophotometry reveals that the protonation chemistry of trans-[MoL(CNPh)(Ph2PCH2CH2PPh2)2] is complicated. It is proposed that in all cases protonation occurs initially at the nitrogen atom of the isonitrile ligand to form trans-[MoL(CNHPh)(Ph2PCH2CH2PPh2)2]+. Only when L=N2 is this single protonation sufficient to labilise L to dissociation, and subsequent binding of Cl− gives trans-[MoCl(CNHPh)(Ph2PCH2CH2PPh2)2]. At high concentrations of HCl a second protonation occurs which inhibits the substitution. It is proposed that this second proton binds to the dinitrogen ligand. When L=CO or H2, a second protonation is also observed but in these cases the second protonation is proposed to occur at the carbon atom of the aminocarbyne ligand, generating trans-[MoL(CHNHPh)(Ph2PCH2CH2PPh2)2]2+. Addition of the second proton labilises the trans-H2 to dissociation, and subsequent rapid binding of Cl− and dissociation of a proton yields the product trans-[MoCl(CNHPh)(Ph2PCH2CH2PPh2)2]. Dissociation of L=CO does not occur from trans-[Mo(CO)(CHNHPh)(Ph2PCH2CH2PPh2)2]2+, but rather migration of the proton from carbon to molybdenum, and dissociation of the other proton produces [MoH(CO)(CNPh)(Ph2PCH2CH2PPh2)2]+. 相似文献
17.
18.
The reaction of the hydrospirophosphorane HP(OCMe2CMe2O)2 ligand or the five-membered cyclic hydrogen phosphonate HP(O)(OCMe2CMe2O) ligand with the ReOCl3(OPPh3)(SMe2) precursor under controlled reaction conditions led to the isolation of dimeric oxo-rhenium(V) complexes containing P(O)(OCMe2CMe2O)− moieties, represented by [ReOCl2{μ-OP(OCMe2CMe2O)}3ReOCl(OPPh3)] (1) and [ReOCl2(SMe2){μ-OP(OCMe2CMe2O)}]2 (2). The chemical composition of these complexes was established by means of NMR, IR spectroscopic methods, and based on analytical data. The relative stereochemistry of 1 and 2 was unambiguously determined by single X-ray diffraction studies. The crystal structure of 1 comprises two crystallographically independent molecules in an asymmetric unit and co-crystallised molecules of both dichloromethane and acetonitrile. Two different six-coordinated monomeric subunits, ReOCl2 and ReOCl(OPPh3), connected by three phosphonate bridges, build up the dinuclear complex 1. It exhibits an uncommon feature, a cis disposition of the triphenylphosphine oxide molecule relative to the terminal ReO bond. The crystal structure of 2 includes four molecules, in which two equivalent rhenium subunits ReOCl2(SMe2) are linked by two P(O)(OCMe2CMe2O)− bridges. 相似文献
19.
P.A. Abramov M.N. Sokolov E.V. Peresypkina N.K. Moroz R. Hernandez-Molina M.C. Arévalo 《Inorganica chimica acta》2011,375(1):314-319
New cluster complex [Mo3SeO3(acac)3(py)3]+ was obtained by ligand substitution in the aqua complex [Mo3SeO3(H2O)9]4+. Crystal structure was determined for [Mo3SeO3(acac)3(py)3]PF6·C6H5CH3. The complex was characterized by 77Se NMR, electrospray mass-spectrometry, and cyclic voltammetry. DFT calculations were used to confirm the assignment of chemical shift and to study Mo-Mo bonding in the cluster core. 相似文献
20.
Rehan Basta 《Inorganica chimica acta》2004,357(13):3883-3888
The reactions of Zr(C5H5)(6,6-dmch)(PMe3)2 and Zr(6,6-dmch)2(PMe3)2 (dmch=dimethylcyclohexadienyl) with CO lead to the selective replacement of one PMe3 ligand by CO. Both carbonyl complexes have been structurally characterized. Additionally, the reaction of the latter complex with PhC2SiMe3 leads to a similar replacement of one PMe3 ligand, involving simple coordination of the alkyne, rather than any coupling to the dmch ligand. 相似文献