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1.
Konstantinos D. Demadis Edward M. Kober Peter S. White 《Inorganica chimica acta》2007,360(3):1143-1153
Structural changes between [OsIIL3]2+ and [OsIIIL3]3+ (L: 2,2′-bipyridine; 1,10-phenanthroline) and molecular and electronic structures of the OsIII complexes [OsIII(bpy)3]3+ and [OsIII(phen)3]3+ are discussed in this paper. Mid-infrared spectra in the ν(bpy) and ν(phen) ring stretching region for [OsII(bpy)3](PF6)2, [OsIII(bpy)3](PF6)3, [OsII(phen)3](PF6)2, and [OsIII(phen)3](PF6)3 are compared, as are X-ray crystal structures. Absorption spectra in the UV region for [OsIII(bpy)3](PF6)3 and [OsIII(phen)3](PF6)3 are dominated by very intense absorptions (ε = 40 000-50 000 M−1 cm−1) due to bpy and phen intra-ligand π → π∗ transitions. In the visible region, relatively narrow bands with vibronic progressions of ∼1500 cm−1 appear, and have been assigned to bpy or phen-based, spin-orbit coupling enhanced, 1π → 3π∗ electronic transitions. Also present in the visible region are ligand-to-metal charge transfer bands (LMCT) arising from π(bpy) → t2g(OsIII) or π(phen) → t2g(OsIII) transitions. In the near infrared, two broad absorption features appear for oxidized forms [OsIII(bpy)3](PF6)3 and [OsIII(phen)3](PF6)3 arising from dπ-dπ interconfigurational bands characteristic of dπ5OsIII. They are observed at 4580 and 5090 cm−1 for [OsIII(bpy)3](PF6)3 and at 4400 and 4990 cm−1 for [OsIII(phen)3](PF6)3. The bpy and phen infrared vibrational bands shift to higher energy upon oxidation of Os(II) to Os(III). In the cation structure in [OsIII(bpy)3](PF6)3, the OsIII atom resides at a distorted octahedral site, as judged by ∠N-Os-N, which varies from 78.78(22)° to 96.61(22)°. Os-N bond lengths are also in general longer for [OsIII(bpy)3](PF6)3 compared to [OsII(bpy)3](PF6)2 (0.010 Å), and for [OsIII(phen)3](PF6)3 compared to [OsII(phen)3](PF6)2 (0.014 Å). Structural changes in the ligands between oxidation states are discussed as originating from a combination of dπ(OsII) → π∗ (bpy or phen) backbonding and charge redistribution on the ligands as calculated by natural population analysis. 相似文献
2.
The reaction of 2 equiv. of [Os3(CO)10(MeCN)2] with R-CC-L-CC-R (R = H, L = (C4H2S); R = SiMe3, L = (C4H2S-C4H2S), (C4H2S-C4H2S-C4H2S), (C4H2S)-(C14H8)-(C4H2S)) affords the series of linked clusters [{Os3(CO)10}(HCC(C4H2S)CCH){Os3(CO)10}] (1), [{Os3(CO)10}(Me3SiCC(C4H2S-C4H2S)CCSiMe3){Os3(CO)10}] (2), [{Os3(CO)10}(Me3SiCC(C4H2S-C4H2S-C4H2S)CCSiMe3){Os3(CO)10}] (4) and [{Os3(CO)10}(Me3SiCC(C4H2S)-(C14H8)-(C4H2S)CCSiMe3){Os3(CO)10}] (6) as the major products. The complexes have been characterised by a range of spectroscopic methods and, in the case of 1 and 2 by single crystal X-ray crystallography. The alkyne groups cap the osmium triangles in the expected μ3-η2-||-bonding mode and each triangle is coordinated by nine terminal and one μ2-carbonyl group. Solution UV-Vis spectra of the complexes were similar to those observed for the free ligands consistent with there being little delocalisation between the cluster units and the thiophene groups. 相似文献
3.
A new complex of composition [Cu(2-NO2bz)2(nia)2(H2O)2] (1) (nia = nicotinamide, 2-NO2bz = 2-nitrobenzoate) has been prepared and its composition and stereochemistry as well as coordination mode have been determined by elemental analysis, electronic, infrared and EPR spectroscopy, magnetization measurements over the temperature range 1.8-300 K, and its structure has been solved, as well. The complex structure consists of the centrosymmetric molecules with Cu(II) atom monodentately coordinated by the pair of 2-nitrobenzoato anions and by the pair of nicotinamide molecules, forming nearly tetragonal basal plane, and by a pair of water molecules that complete tetragonal-bipyramidal coordination polyhedron about the copper atom. The complex 1 exhibits magnetic moment μeff = 1.86 B.M. at 300 K which decreases to μeff = 1.83 B.M. at 1.8 K. The magnetic susceptibility temperature dependence obeys Curie-Weiss law with Curie constant of 0.442 cm3 K mol−1 and with Weiss constant of −1.0 K. EPR spectra at room temperature as well as at 77 K are of axial type with g⊥ = 2.065 and g∥ = 2.280 and exhibit clearly, but partially resolved parallel hyperfine splitting with AII = 160 G, that is consistent with the determined molecular structure of 1. In order to analyze the factors influencing the degree of tetragonal distortion of coordination polyhedron, the dataset of 72 structures similar to that of 1 was extracted from CCD and analyzed. A significant correlation between the average Cu-Oax bond length and tetragonality parameter τ which was found as a consequence of the Jahn-Teller effect. 相似文献
4.
Raman spectroscopy was used to determine the conformation of the disulfide linkage between cysteine residues in the homodimeric construct of the N-terminal alpha helical domain of surfactant protein B (dSP-B1-25). The conformation of the disulfide bond between cysteine residues in position 8 of the homodimer of dSP-B1-25 was compared with that of a truncated homodimer (dSP-B8-25) of the peptide having a disulfide linkage at the same position in the alpha helix. Temperature-dependent Raman spectra of the S-S stretching region centered at ∼ 500 cm− 1 indicated a stable, although highly strained disulfide conformation with a χ(CS-SC) dihedral angle of ± 10° for the dSP-B1-25 dimer. In contrast, the truncated dimer dSP-B8-25 exhibited a series of disulfide conformations with the χ(CS-SC) dihedral angle taking on values of either ± 30° or 85± 20°. For conformations with χ(CS-SC) close to the ± 90° value, the Raman spectra of the 8-25 truncated dimers exhibited χ(SS-CC) dihedral angles of 90/180° and 20-30°. In the presence of a lipid mixture, both constructs showed a ν(S-S) band at ∼ 488 cm− 1, corresponding to a χ(CS-SC) dihedral angle of ± 10°. Polarized infrared spectroscopy was also used to determine the orientation of the helix and β-sheet portion of both synthetic peptides. These calculations indicated that the helix was oriented primarily in the plane of the surface, at an angle of ∼ 60-70° to the surface normal, while the β structure had ∼ 40° tilt. This orientation direction did not change in the presence of a lipid mixture or with temperature. These observations suggest that: (i) the conformational flexibility of the disulfide linkage is dependent on the amino acid residues that flank the cysteine disulfide bond, and (ii) in both constructs, the presence of a lipid matrix locks the disulfide bond into a preferred conformation. 相似文献
5.
Ali Canlier 《Inorganica chimica acta》2010,363(1):1-4850
Crystal structure of [ReO2(4-MeOpy)4][PF6] (4-MeOpy = 4-methoxypyridine) complex has been examined by the single crystal X-ray analytical method. This complex shows a trans-dioxo geometry (average Re-O bond length = 1.766(2) Å) and its equatorial plane is occupied by four 4-MeOpy molecules (average Re-N bond length = 2.156(4) Å). Electrochemical reaction of [ReO2(4-MeOpy)4]+ in CH3CN solution containing tetra-n-butylammonium perchlorate as a supporting electrolyte has been studied using cyclic voltammetry at 24 °C. Cyclic voltammograms show one redox couple around 0.65 V (Epa) and 0.58 V (Epc) [versus ferrocene/ferrocenium ion redox couple, (Fc/Fc+)]. Potential differences between two peaks (ΔEp) at scan rates in the range from 0.01 to 0.10 V s−1 are 65 mV, which is almost consistent with the theoretical ΔEp value (59 mV) for the reversible one electron transfer reaction at 24 °C. The ratio of anodic peak currents to cathodic ones is 1.04 ± 0.03 and the (Epa + Epc)/2 value is constant, 0.613 ± 0.001 V versus Fc/Fc+, regardless of the scan rate. Spectroelectrochemical experiments have also been carried out by applying potentials from 0.40 to 0.77 V versus Fc/Fc+ with an optically transparent thin layer electrode. It was found that the UV-visible absorption spectra show clear isosbestic points at 228, 276, and 384 nm, and that the electron stoichiometry is evaluated as 1.03 from the Nernstian plot. These results indicate that the [ReO2(4-MeOpy)4]+ complex is oxidized reversibly to the [ReO2(4-MeOpy)4]2+ complex. Furthermore, it was clarified that the [ReO2(4-MeOpy)4]2+ in CH3CN has the characteristic absorption bands at 236, 278, 330, 478, and 543 nm and their molar absorption coefficients are 4.3 × 104, 4.5 × 103, 1.0 × 104, and 6.1 × 103 M−1 cm−1 (M = mol dm−3), respectively. 相似文献
6.
Leonardo D. Slep Otaciro R. Nascimento María T. Garland Mireille Perec 《Inorganica chimica acta》2007,360(9):2911-2916
A seven-coordinate FeIII complex, [Fe(oda)(H2O)2(NO3)], was obtained after dissolving Fe(NO3)3 · 9H2O in an aqueous solution of oxydiacetic acid (H2oda) at room temperature. In the solid state, the FeIII center adopts a pentagonal bipyramid geometry with an {FeO7} core formed by a tridentate oda2− and a bidentate in the equatorial plane, and two axial water molecules. Magnetic measurements and EPR spectra revealed the presence of S = 5/2 FeIII centers with rhombic zero field splitting parameters (D = 0.81 cm−1, E/D = 0.33 ). Weak antiferromagnetic interactions with J ≈ −0.06 cm−1 operating between neighboring Fe ions connected through Fe-O-C-O?H-O-Fe paths are estimated using the molecular field approximation. 相似文献
7.
The 2-D K(I)-tetrazole metal-organic complex, [K2(4-TPA)2(H2O)2]n (1), which is constructed by the [K2O4N]n inorganic skeleton chains bridged by the 4-TPA linkers, has been synthesized and characterized by single crystal X-ray crystallography and temperature-dependence dielectric constant(ε) measurement under the alternating electric field, (4-TPA = 2-(4-(1H-tetrazol-5-yl)pyridinium-1-yl) acetate). The ε of temperature dependence remains unchanged almost within the measured temperature range of 90 K to 430 K at 1 M Hz, and the ε of frequency dependence shows a significant decline from 6.7 to 4.6 within the measured frequency range of 200-1 MHz at room temperature. And it is consistent with the low dielectric loss (ε2/ε1) behavior, which is attributed to the highly ordered polarization mechanism. 相似文献
8.
Flash photolysis with time-resolved infrared (TRIR) spectroscopy was used to elucidate the photochemical reactivity of the hydroformylation catalyst precursor Co2(CO)6(PMePh2)2. Depending on reaction conditions, the net products of photolysis varied significantly. A model is presented that accounts for the net reactivity with two initial photoproducts, the 17-electron species Co(CO)3(PMePh2) and the coordinatively unsaturated dimer Co2(CO)5(PMePh2)2. No evidence was found for photochemical formation of Co2(CO)6(PMePh2). Time-resolved spectroscopic studies allowed for the direct observation of transient species and for kinetics studies of certain reactions; for example, the reactions of Co(CO)3PMePh2 with CO and with PMePh2 gave the respective rate constants 1.5 × 105 and 1.2 × 107 M−1 s−1, while the analogous reactions with Co2(CO)5(PMePh2)2 gave the rate constants of 2.6 × 106 M−1 s−1 and 3.9 × 107 M−1 s−1. 相似文献
9.
Yi-Shan Song 《Inorganica chimica acta》2005,358(1):191-195
A novel chain-like luminescent samarium coordination polymer {Sm3(C8H4O4)4(C12N2H8)2(NO3)}n (C8H4O4 = phthalate, C12N2H8 = 1,10-phenanthroline) has been assembled by hydrothermal process. The title complex crystallizes in the monoclinic system, space group P2(1)/c, with lattice parameters a = 22.56(3) Å, b = 11.155(15) Å, c = 20.32(3) Å, β = 96.70(2)°, V = 5078(12) Å3, F(000) = 2964, GOF = 0.857, R1 = 0.0358, wR2 = 0.0597, Z = 4. Samarium ions exhibit different coordination modes from each other and lead to the unexpected high asymmetrical structure. To our knowledge, it is the first example of lanthanide coordination polymers comprising the three asymmetrical central Sm3+ fragments. The photophysical properties have been studied with excitation and emission spectra. 相似文献
10.
A novel fluorinated iron phosphite Fe2(HPO3)F2 (1) has been hydrothermally synthesized and characterized by single-crystal X-ray diffraction. Compound 1 crystallizes in the orthorhombic space group Pnma (No. 51) with a = 7.3458(15) Å, b = 10.038(2) Å, c = 5.4947(11) Å, V = 405.16(14) Å3, Z = 4. Its structure is built up from iron(II) oxygen-fluorine FeO3F3 octahedra and HPO3 pseudo-tetrahedra, giving rise to a 3D inorganic framework. The infinite -Fe-O-Fe-F-Fe- linkage and -Fe-F-Fe- layer in the framework are the noteworthy structural features. Mössbauer spectrum shows the presence of Fe2+ in the octahedral coordination. Magnetic measurements indicate the existence of antiferromagnetic interactions. 相似文献
11.
Using incoherent quasi-elastic and inelastic neutron scattering, we have investigated the hydrogen relaxational dynamics and hydrogen vibrational modes in the polyoxomolybdate specie [Mo72Fe30O252(CH3COO)12[Mo2O7(H2O)]2[H2Mo2O8(H2O)](H2O)91]· ≈ 150 H2O. The translational dynamics of the water molecules in the compound is profoundly different from that of bulk water at the same temperature showing a non-Debye relaxation behavior. The temperature dependence of the relaxation time can be described in terms of an Arrhenius law, indicating that the dynamics is triggered by the breaking of the bonds connecting the crystal water molecules with the hydrophilic nanocapsule surfaces. Inelastic neutron scattering spectra confirm the attenuation of water translational modes with respect to the bulk water case due to the strong destructuring effect imposed by the nanocage interface and the enhancement of the highest frequency librational mode as already found in hydrated Vycor or Gelsil matrix. Small angle X-ray scattering on freshly prepared aqueous solution evidences the presence of nanocapsule structures proper of the monomer (2.6 nm in diameter) that coexist with a small amount of oligomers. After 1 month the polyoxomolibdate specie self-assembles in a supramolecular structure with a polydisperse distribution of dimensions spanning from the monomer to the “blackberry” vesicular structure already reported in literature. 相似文献
12.
A series of osmium(VI) nitrido complexes containing pyridine-carboxylato ligands OsVI(N)(L)2X (L = pyridine-2carboxylate (1), 2-quinaldinate (2) and X = Cl (a), Br (1b and 2c) or CH3O (2b)) and [OsVI(N)(L)X3]− (L = pyridine-2,6-dicarboxylate (3) and X = Cl (a) or Br (b)) have been synthesised. Complexes 1 and 2 are electrophilic and react readily with various nucleophiles such as phosphine, sulfide and azide. Reaction of OsVI(N)(L)2X (1 and 2) with triphenylphosphine produces the osmium(IV) phosphiniminato complexes OsVI(NPPh3)(L)2X (4 and 5). The kinetics of nitrogen atom transfer from the complexes OsVI(N)(L)2Br (2c) (L = 2-quinaldinate) with triphenylphosphine have been studied in CH3CN at 25.0 °C by stopped-flow spectrophotometric method. The following rate law is obtained: −d[Os(VI)]/dt = k2[Os(VI)][PPh3]. OsVI(N)(L)2Cl (L = 2-quinaldinate) (2a) reacts also with [PPN](N3) to give an osmium(III) dichloro complex, trans-[PPN][OsIII(L)2Cl2] (6). Reaction of OsVI(N)(L)2Cl (L = 2-quinaldinate) (2a) with lithium sulfide produces an osmium(II) thionitrosyl complex OsII(NS)(L)2Cl (7). These complexes have been structurally characterised by X-ray crystallography. 相似文献
13.
Mikhail N. Bochkarev Georgy V. Khoroshenkov Dmitry M. Kuzyaev Anatoly A. Fagin Mikhail E. Burin Georgy K. Fukin Eugeny V. Baranov Alexander A. Maleev 《Inorganica chimica acta》2006,359(10):3315-3320
It was found that the lanthanide diiodides LnI2 (1) (Ln = Nd, Sm, Eu, Dy, Tm, Yb) are dissolved in isopropylamine (IPA) without redox transformations. Stability of the formed solutions decreases in a row Eu ≈ Yb > Sm > Tm > Dy > Nd. Removing of a solvent in vacuum leaves complexes LnI2(IPA)x (2) (Nd, x = 5; Sm, Eu, Dy, Tm, Yb, x = 4) as crystalline colored solids. Stability of 2-Nd,Dy,Tm is higher than that of known THF or DME coordinated salts. Divalent state of metal in the products is confirmed by data of UV-Vis spectroscopy, magnetic measurements and their chemical behavior. Structure of 2-Eu and 2-Tm was established by X-ray diffraction analysis. Oxidation of 2-Nd,Dy in IPA affords amine-amides (PriNH)Ln(IPA)y (3) (Nd, y = 4; Dy, x = 3). n-Propylamine also dissolves the iodides 1-Sm,Eu,Dy,Tm,Yb but stability of the solutions is significantly lower. 1-Nd vigorously reacts with PrnNH2 even at −30 °C which hampers the formation of the solution. 相似文献
14.
Thomas Schölkopf 《Inorganica chimica acta》2011,374(1):181-186
The orthorhombically crystallizing salts Rb2[B12(OH)12]·2H2O (a = 1576.81(9), b = 813.08(5), c = 1245.32(7) pm) and Rb2[B12(OH)12]·2H2O2 (a = 1616.54(9), b = 814.29(5), c = 1260.12(7) pm) could be prepared from Rb2[B12H12] and hydrogen peroxide. Both crystal structures were determined by X-ray single crystal diffraction and refined in the space group Cmce. They are not isostructural to the other compounds containing icosahedral dodecahydroxo-closo-dodecaborate dianions [B12(OH)12]2− and potassium, rubidium or cesium cations already known to literature, but both title compounds crystallize quasi-isotypically exhibiting Rb+ cations in 10-fold oxygen coordination. The hydrogen peroxide adduct (Rb2[B12(OH)12]·2H2O2) is explosive on shock and heat, while the hydrate (Rb2[B12(OH)12]·2H2O) is not. 相似文献
15.
The binuclear mixed valence copper(I/II) compound [CuI(CN)3CuII(tn)2] (1) (tn = propane-1,3-diamine) and its acetonitrile adduct [CuI(CN)3CuII(tn)2] · 2MeCN (2) have been synthesized. Complex 1 crystallizes triclinic, space group , a = 8.117(2) Å, b = 8.389(2) Å, c = 11.920(2) Å, α = 108.728(3)°, β = 100.024(3)°, γ = 104.888(4)°, Z = 2, and compound 2 monoclinic, space group P21/m, a = 8.752(2) Å, b = 13.243(3) Å, c = 9.549(2) Å, β = 114.678(4)°, Z = 2. In both crystal structures, the binuclear [CuI(CN)3CuII(tn)2] complex with slightly different bonding geometries is formed. One of the three nitrogen atoms of a CuI(CN)3 moiety is coordinated to Cu(II) at the apex of a square-pyramid with two chelating ligands tn on its base. The shortest intramolecular CuII?CuII distance in 1 is 5.640(7) Å. The EPR behaviour of 1 has been investigated at room temperature and at 77 K. The magnetic properties were measured in the temperature range 1.8-300 K. 相似文献
16.
Infrared, far-infrared and Raman spectra of Re2(O2CCH3)4X2 (X = Cl, Br) and Re2(O2CCD3)4Cl2 have been recorded. Assignments of the vibrational spectra of Os2(O2CCH3)4Cl2 and its deuterated derivative have been completed together with the Re complexes on the basis of normal-coordinate analysis. Force constant calculation was made for the acetate ion as well as for a four-atomic unit (with the CH3 and CD3 groups considered as point masses) using optimized masses of 16.7, 17.8, 20.5 and 21.6 for 12CH3, 13CH3, 12CD3 and 13CD3 groups, respectively. The force constants of the acetate ion have been adopted to the starting force field of the M2(O2CCH3)4X2 type complexes. The metal-halide (0.889, 0.997 and 1.286 N cm−1) and metal-metal stretching (3.32, 3.34 and 3.57 N cm−1) force constants were obtained for Re2(O2CCH3)4Cl2Re2(O2CCH3)4Br2 and Os2(O2CCH3)4Cl2 complexes, respectively. It was shown that the so-called diatomic approximation in most cases overestimates the M-M stretching force constants by 30-40%. Much better correlation has been obtained to fit these force constants, which produced values very close to those obtained by full normal-coordinate calculations. The Re-Re stretching force constants showed a reasonable correlation with the Re-Re bond distances for 18 rhenium complexes. 相似文献
17.
The reaction of with Co(dmgBF2)2(H2O)2 in 1.0 M HClO4/LiClO4 was found to be first-order in both reactants and the [H+] dependence of the second-order rate constant is given by k2obs = b/[H+], b at 25 °C is 9.23 ± 0.14 × 102 s−1. The [H+] dependence at lower temperatures shows some saturation effect that allowed an estimate of the hydrolysis constant for as Ka = 9.5 × 10−3 M at 10 and 15 °C. Marcus theory and the known self-exchange rate constant for Co(OH2)5OH2+/+ were used to estimate an electron self-exchange rate constant of k22 = 1.7 × 10−4 M−1 s−1 for . 相似文献
18.
Reaction of NH4VO3 with 2,6-pyridinedimethanol in water at 85 °C followed by the room temperature addition of HCl (aq) yields [HVO2(pydim)]x (pydim = 2,6-pyridinedimethanolato dianion), as a sparingly soluble off-white solid. This acid may be deprotonated by titration with NaOH (aq), yielding Na[VO2(pydim)] · 4H2O, which has been structurally characterized by single-crystal X-ray diffraction. Treating Na[VO2(pydim)] · 4H2O with HCl (aq) regenerates [HVO2(pydim)]x, but reaction with additional NaOH (aq) displaces the pyridinedimethanolato ligand from the vanadium center. Similarly, treating [HVO2(pydim)]x with excess HCl (aq) strips the pyridinedimethanolato ligand from the vanadium center and yields the adduct [H3(pydim)]+Cl− as one component in a mixture of products. This adduct has been structurally characterized by single-crystal X-ray diffraction. The optimum pH range for stable dioxovanadium(V) complexes stabilized by the 2,6-pyridinedimethanolato ligand is at least 1.5-9.4. 相似文献
19.
The structures and relative energies of the As2Co2(CO)n (n = 6, 5, 4) derivatives are predicted by density functional theory to be analogous to those of the corresponding H2C2Co2(CO)n derivatives. Thus As2Co2(CO)6 is predicted to have three carbonyls on one cobalt atom eclipsed relative to the three carbonyls on the other cobalt atom. The corresponding As2Co2(CO)6 structure with a staggered rather than eclipsed arrangement of the Co(CO)3 units is a transition state rather than a genuine minimum. For As2Co2(CO)5 the structure in which an equatorial group is removed from the As2Co2(CO)6 structure and a singly bridged As2Co2(CO)4(μ-CO) structure are predicted to have essentially the same energies, within <2 kcal/mol. A higher energy As2Co2(CO)5 structure by 9 ± 2 kcal/mol is derived from the As2Co2(CO)6 structure by removal of an axial carbonyl group. The two unbridged As2Co2(CO)5 structures correspond to those observed experimentally in the photolysis of As2Co2(CO)6 in Nujol matrices at low temperatures. In such photolysis experiments the higher energy isomer is produced initially and then converted to the lower energy isomer upon annealing. A singly bridged structure was found for As2Co2(CO)4. The analogous structure was not observed in the previous work with H2C2Co2(CO)4. However, such a H2C2Co(CO)3(μ-CO) structure is found here for the acetylene complex. This singly bridged structure is predicted to lie 1.9 kcal/mol below the H2C2Co2(CO)44-1S structure by the BP86 method but 3.5 kcal/mol above the latter by the B3LYP method. In addition to the singly bridged As2Co2(CO)4 structure, the same six unbridged structures were located for As2Co2(CO)4 that were previously found for H2C2Co2(CO)6. 相似文献
20.
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