The synthesis and properties of polynuclear complexes of general formulae [M(RIm)(diolefin)x, [M(RIm)(CO)2]x and [M(RIm)(CO)L]x (M Rh, Ir; RIm imidazolate, 2-methylimidazolate, 2-benzylbenzimidazolate; L PPh3 or P(OPh)3) are reported. The crystal structure of the novel complex [Rh(2-MeIm)-(CO)2]4 (2-MeIm 2-methylimidazolate) has been determined by X-ray methods. The crystals are orthorhombic, space group P212121, with Z 4 in a unit cell of dimensions a 19.427(12), b 13.419(8), c 12.346(9) Å. The structure has been solved by combined Patterson and direct methods and refined by full-matrix least-squares to R 0.043 for 937 independent observed reflections. It consists of discrete tetrameric complexes in which each Rh atom is in a nearly cis square planar arrangement, bonded to two carbon atoms of carbonyl groups and to two nitrogen atoms of two 2-methylimidazolate ligands, each of which, acting as an exo-bidentate ligand, bridging two metal atoms, so that the four bridging 2-MeIm ligands and the four Rh atoms form a multiatomic ring. 相似文献
The preparation and properties of complexes of general formulae [Rh(CS)-(HL)(PR3)2]ClO4 (HL = pyrazole (HPz), 3-methylpyrazole (H3-MePz), 3,5-dimethylpyrazole (H3,5-Me2Pz), PR3 = triphenylphosphine, tricyclohexylphosphine) and [(PR3)2(CS)Rh(μ-Pz)AuPPh3]ClO4 are reported. Complexes of the first set react with potassium hydroxide to give [Rh(μ-L)(CS)(PPh3)2 or RhPz(CS)(PR3)2 complexes. The structure of the complex [Rh(3,5-Me2Pz)(CS)(PPh3)]2 has been determined by X-ray diffraction methods. The crystals are monoclinic, space group P21/c, with Z = 4 in a unit cell of dimensions a = 12.700(11), b = 17.217(16), c = 23.041(18) Å, β = 116.55(8)°. The structure has been solved by Patterson and Fourier methods and refined by full-matrix least-squares to R = 0.059 for 1978 independent reflections. The structure consists of dimeric complexes, in which each rhodium atom is in a square-planar environment being bonded to a carbon atom of a thiocarbonyl ligand, a phosphorus atom of a triphenylphosphine molecule and to two nitrogen atoms of pyrazolate ligands bridging the metal atoms. The dihedral angle of 71.1° between such two square planes leads to a bent configuration with an intramolecular rhodium-rhodium distance of 3.220 Å. The thiocarbonyl and triphenylphosphine ligands are in a trans disposition. 相似文献
Cyclohexane solutions of [W(Cp)(CO)3]2 and [Mo(Cp)(CO)3]2 exhibit weak bimodal emission spectra when excited With 354 nm picosecond pulses, but do not luminesce when pumped at 530 nm. Picosecond lifetimes characterize the short-wavelength, emission bands, which may originate from metal-cyclopentadienyl CT excited states. 相似文献
Summary The carbonyl ligands in the Rh1 complexes Rh(L-L)(CO)2 [L-L=anthranilate (AA) orN-phenylanthranilate(FA) ions] are replaced by P(OPh)3 to form the mono-or disubstituted products, Rh(L-L)(CO)[P(OPh)3] and Rh(L-L)[P(OPh)3]2 respectively depending on the [P(OPh)3]/[Rh] molar ratio, at room temperature and in air. Under argon at [P(OPh)3]/[Rh]4 theortho-metallated Rh1 complex Rh[P(OPh)3]3[P(OC6H4)-OPh)2] is formed. The new route forortho-metallated Rh1 complex synthesis is described.The Rh(AA)(CO)2 complex was used as a catalyst precursor in hydroformylation of olefins. 相似文献
The preparation and properties of cationic rhodium complexes of the type [Rh(diolefin)L2]ClO4 (diolefin COD, NBD; L sulfur donor ligand) are described. Pentacoordinated complexes of general formula [Rh(NBD)2L]ClO4 (L SMe2, SEt2, tetrahydrothiophen or trimethylene sulfide) are also reported. The crystal structure of [Rh(NBD)2(Set2)]ClO4 has been determined by X-ray methods. The crystals are rhombohedral, space group R3c, with a 14.530(7) Å and α 77.86(5)° (Z = 6). The structure was solved from diffractometer data by direct and Fourier methods and refined by full-matrix least-squares to R = 0.054 for 937 independent observed reflections. In the cationic [Rh(NBD)2(SEt2)]+ complex the Rh atom is pentacoordinated, the geometry about the metal being a square pyramid whose base is defined by the midpoints of the olefin bonds from two norbornadiene molecules and the apex is occupied by a sulfur atom of the thioether ligand at a rather long distance [Rh?S 2.500(4) Å]. 相似文献
The iridium and rhodium complexes [MCl(CO)2(NH2C6H4Me-4)] (M = Ir or Rh) react with [Os3(μ-H)2(CO)10] to give the tetranuclear clusters [MOs3(μ-H)2(μ-Cl)(CO)12]; the iridium compound being structurally identified by X-ray diffraction. Similarly, [IrCl(CO)2(NH2C6H4Me-4)] and [Rh2(μ-CO)2(η-C5Me5)2] afford the tetranuclear cluster [Ir2Rh2(μ-CO)(μ3-CO)2(CO)4(η-C5Me5)2], also characterised by single-crystal X-ray crystallog 相似文献
An XRD analysis is used to study the single crystal of [Pd(NH3)4][Rh(NH3)(NO2)5] double complex salt at T = 150(2) K. Crystallographic characteristics are as follows: a = 7.6458(5) ?, b = 9.8813(6) ?, c = 9.5788(7) ?, β = 109.469(2)°, V = 682.30(8) ?3, P21/m space group, Z = 2, dx = 2.553 g/cm3. The geometry of the complex [Rh(NH3)(NO2)5]2− anion is described for the first time: Rh-N(NO2) distances are 2.020(4)–2.060(3) ?, Rh-N(NH3) 2.074(4) ?, N(NO2)-Rh-N(NH3) trans-angle is 178.8(2)°. 相似文献
A study has been carried out of the catalytic activity of the systems formed by [HRh{P(OPh)3}4] or [HRh(CO){P(OPh)3}3] with the modifying ligands P(OPh)3, PPh3, diphos and Cp2Zr(CH2PPh2)2 in hydroformylation of hex-1-ene (at p = 5 bar). The best results were obtained with the system [HRh{P(OPh)3}4]+Cp2Zr(CH2PPh2)2 (75–85% yeild of aldehydes). 相似文献
The thermal decomposition of the complexes trans-[Pt(X)(CH3)L2] (L P(C2H5)3; X Cl, Br, I, CN) in decalin at 170 and 200°C affords methane platinum metal and [Pt(X)2L2]. The kinetics of the decomposition of the complexes were determined by monitoring the appearance of methane by GLC. The observed first-order rate constant was found to be independent on the nature of the ligand X. The thermal decomposition of the trideuteriomethyl complexes [Pt(X)(CD3)L2] (X I, CN) in decalin-d18 at 170 and 200°C was studied by GLC/MS. The thermolysis affords CD3H and CD4 in ratios which are independent of the nature of X and of the temperature used. The mass spectra of the complexes were also examined. A relative scale of platinum-to-methyl bond dissociation energies has been established by measuring the appearance potential of the fragment ion [Pt(X)L2]+ and the ionization energies in the series [Pt(X)(CH3)L2]. Ionization potentials and PtCH3 bond energies show a clear dependence on the nature of X which is not reflected in corresponding changes in the decomposition rates. 相似文献
An X-ray crystal structure determination for the bimetallic complex Mn2(CO)8-[P(NMe2)3]2 reveals that the P(NMe2)3 ligands are trans to the Mn---Mn bond and the Mn---Mn bond distance is relatively long, 2.946(1) Å. 相似文献
An investigation into the effect of the flexibility of substituents on the disorder of the Cl-Rh-CO moiety in Vaska-type trans-[Rh(CO)Cl(PR3)2] complexes is presented. The influence of the packing of the complexes with PR3 = P(CH2C6H5)3, P(OC6H5)3, P(O-2-MeC6H4)3 and P(O-2,6-Me2C6H3)3 was evaluated by comparing the X-ray structures with the results of DFT calculations on these complexes. Reasonable agreement between the calculated and molecular structures was found. A good agreement, however, was found between the calculated and crystallographic structures when comparing the coordination polyhedron around the Rh atom. The main difference between the calculated and solid state structures appeared to be in the orientation of the phenyl groups of the P-donor ligands. 相似文献
The reduction of RhCl3 - 3 H2O by sodium amalgam in THF solution under an atmosphere of N2 and in the presence of an excess of a phosphine ligand has resulted in the formation of the hydridodinitrogen complexes RhH(N2)-(PPh(t-Bu)2)2 (I), RhH(N2)(P(t-Bu)3)2 (II), and [RhH(P(cyclo-C6H11)3)2]2(μ-N2)(V), and a hydridotrisphosphine complex RhH(P(i-Pr)3)3 (X). The dinitrogen coordination is stable in I but N2 is readily lost from other dinitrogen complexes, permitting the isolation of three-coordinate hydridobisphosphine rhodium(I) complexes RhH(P(t-Bu)3)2 (VII) and RhH(P(cyclo-C6H11)3)2 (VIII). Trihydrido complexes RhH3L2 (L = PPh(t-Bu)2 (XI), P(t-Bu)3 (XII), P(cyclo-C6H11)2 (XIII), and P(i-Pr)3 (XIV)) have been synthesized by the reaction of the above rhodium (I) compounds with H2. By treatment of the corresponding trihydrido complexes with N2 we have been able to obtain RhH(N2)-(P(cyclo-C6H11)3)2 (III) and RhH(N2)(P(i-Pr)3)2 (IV). Loss of N2 from IV results in the formation of [RhH(P(i-Pr)3)2]2(μ-N2) (VI) and RhH(P(i-Pr)3)2 (IX). The crystal and molecular structure of [RhH(P(i-Pr)3)2]2(μ-N2) (VI) has been determined at —85°C. The compound crystallizes in the triclinic space group CP1 with two molecules in a cell dimensions a 12.703(16), b 16.455(16), c 11.389(8) Å, α 90.25(9), β 103.87(3), γ 97.58(3)°, V 2289 Å3. The final conventional and weighted agreement indices on Fo for Fo2τ3σ(Fo2) are 0.051 and 0.060, respectively. The dinitrogen ligand of VI linearly bridges two planar RhHP2 fragments with NN separation of 1.134(5) Å and an average RhN bond distance of 1.977(6) Å. The dihedral angle between the two RhHP2 fragments is 55.2°. Overall, the dimeric complex effectively has D2 (222) symmetry. 相似文献
Rhodium(I) complexes [Rh(TropNMe)(CO)(PPh3)] (TropNMe = 2-(N-methylamino)tropone, ONC8H9) (1) and [Rh(Trop)(CO)(PPh3)] · Acetone (Trop = Tropolone, O2C7H6) (2) have been synthesized and characterized by single-crystal X-ray diffraction analysis. A distorted square planar geometry about the rhodium(I) metal centre is observed in both compounds 1 and 2. Substitution of an oxygen atom with a methyl functionalized nitrogen atom does not significantly alter the bond distances and angles in the rhodium(I) complex. A theoretical study at B3LYP/6-31G(d) (main group) and LANL2DZ (Rh) level is presented to clarify the solid state behaviour of these complexes. 相似文献
The iridium(I) complex [Ir(CO2Me)(CO)2(PPh3)2] undergoes a transesterification reaction with the alcohols CH2C(R)CH2OH (R = H, Me), MeCCCH2CH2OH, and HOCH2CH2OH to afford the complexes [Ir(CO2CH2CH2CMe)(CO)2(PPh3)2] and [Ir(CO2CH2CH2OH)(CO)2(PPh3)2], respectively. In contrast the acetylenic alcohol HCCCH2CH2OH gives [Ir(CCCH2CH2OH)(CO)PPh3)2]. Some reactions of the new complexes are described. 相似文献
[Rh(PhCOCHCOCH2CH2CH3)(CO)2] is characterised by crystallographic and density functional theory computational methods. The experimental structure is compared to the calculated structure, as well as to the structurally similar compound [Rh(PhCOCHCOCH2CH3)(CO)2] using root-mean-square calculations and a half-normal probability plot analyses. 相似文献
The transition state for the oxidative addition reaction [Rh(acac)(P(OPh)3)2] + CH3I, as well as two simplified models viz. [Rh(acac)(P(OCH3)3)2] and [Rh(acac)(P(OH)3)2], are calculated with the density functional theory (DFT) at the PW91/TZP level of theory. The full experimental model, as well as the simplified model systems, gives a good account of the experimental Rh-ligand bond lengths of both the rhodium(I) and rhodium(III) β-diketonatobis(triphenylphosphite) complexes. The relative stability of the four possible rhodium(III) reaction products is the same for all the models, with trans-[Rh(acac)(P(OPh)3)2(CH3)(I)] (in agreement with experimental data) as the most stable reaction product. The best agreement between the theoretical and experimental activation parameters was obtained for the full experimental system. 相似文献
The title compound can be prepared in good yield by heating either [Ru4(μ-H)4(CO)12] or [Au2Ru4(μ3-H)2(CO)12(PPh3)2] with [AuMe(PPh3)] in toluene. The related compound [Au3Ru4(μ3-H)(μ-dppm)(CO)12(PPh3)] has also been prepared. Both trigoldtetraruthenium clusters undergo dynamic behaviour in solution, involving intramolecular rearrangement of the metal core, as revealed by variable temperature NMR studies. The crystal structure of [Au3Ru4(μ3-H)(CO)12(PPh3)3] has been established by an X-ray diffraction study. The metal atom core comprises a trigonal bipyramidal AuRu4 unit with two AuRu2 faces capped by gold atoms. 相似文献
The clectrochemical behaviour of the complexes [RuII(L)(CO)2Cl2], [RuII(L)(CO)Cl3][Me4N] and [RuII(L)(CO)2(CH3CN)2][CF3SO3]2 (L = 2,2′-bipyridine or 4,4′-isopropoxycarbonyl-2,2′-bipyridine) has been investigated in CH3CN. The oxidation of [Ru(L)(CO)2Cl2] produces new complexes [RuIII(L)(CO)(CH3CN)2Cl]2+ as a consequence of the instability of the electrogenerated transient RuIII species [RuIII(L)(CO)2Cl2]+. In contrast, the oxidation of [RuII(L)(CO)Cl3][Me4N] produces the stable [RuIII(L)(CO)Cl3] complex. In contrast [RuII(L)(CO)2(CH3CN)2][CF3SO3]2 is not oxidized in the range up to the most positive potentials achievable. The reduction of [RuII(L)(CO)2Cl2] and [RuII(L)(CO)2(CH3CN)2][CF3SO3]2 results in the formation of identical dark blue strongly adherent electroactive films. These films exhibit the characteristics of a metal-metal bond dimer structure. No films are obtained on reduction of [RuII(L)(CO)Cl3][Me4N]. The effect of the substitution of the bipyridine ligand by electron-withdrawing carboxy ester groups on the electrochemical behaviour of all these complexes has also been investigated. 相似文献
Detailed procedures for the syntheses of Os(CO)2(PPh3)3, Os(CO)(CNR)-(PPh3)3 (R = p-tolyl), Os(CO)(CS)(PPh3)3 and Os(CS)(CNR)(PPh3)3, together with the derived complexes Os(CO)2(CS)(PPh3)2, Os(CO)(CS)(CNR)(PPh3)2, Os(η2-C2H4)(CO)(CNR)(PPh3)2, Os(η2-C2H4)(CO)(CS)(PPh3)2, Os(η2CS2)(CO)2-(PPh3)2, Os(η2CS2)(CO)(CS)(PPh3)2, Os(η2-CS2)(CO)(CNR)(PPh3)2, Os(η2PhC2Ph)(CO)2(PPh3)2 and OsH(C2Ph)(CO)2(PPh3)2 are described. 相似文献
