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1.
Christian Slugovc Eva Rüba Roland Schmid Karl Kirchner Kurt Mereiter 《Monatshefte für Chemie / Chemical Monthly》2000,18(7):1241-1251
This article gives an overview of recent chemistry based on the tris-acetonitrile complex [RuCp(CH3CN)3]+. Due to the labile nature of the CH3CN ligands, substitution reactions are a dominant feature of this complex. Important derivatives are the highly reactive complexes [RuCp(PR 3)(CH3CN)2]+ which are a source of the 14e− fragment [RuCp(PR 3)]+. These species are catalytically active in the redox isomerization of allyl alcohols to give aldehydes and ketones. Furthermore, the cationic complex [RuCp(κ1(P),η2-PPh2CH2CH2CH*CH2)(CH3CN)]PF6 derived from the reaction of [RuCp(CH3CN)3]+ with PPh2CH2CH2CH*CH2 is a model compound for studying coupling reactions of olefins and acetylenes. In addition, [RuCp(CH3CN)3]+ is a valuable precursor for the synthesis of configurationally stable chiral three-legged piano-stool ruthenium complexes. These are currently being intensively investigated as Lewis acid catalysts in asymmetric synthesis. 相似文献
2.
Marie-Noëlle Collomb-Dunand-Sauthier Alain Deronzier Raymond Ziessel 《Journal of Electroanalytical Chemistry》1993,350(1-2)
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
3.
Christian Slugovc Eva Rüba Roland Schmid Karl Kirchner Kurt Mereiter 《Monatshefte für Chemie / Chemical Monthly》2000,131(12):1241-1251
Summary. This article gives an overview of recent chemistry based on the tris-acetonitrile complex [RuCp(CH3CN)3]+. Due to the labile nature of the CH3CN ligands, substitution reactions are a dominant feature of this complex. Important derivatives are the highly reactive complexes
[RuCp(PR
3)(CH3CN)2]+ which are a source of the 14e− fragment [RuCp(PR
3)]+. These species are catalytically active in the redox isomerization of allyl alcohols to give aldehydes and ketones. Furthermore,
the cationic complex [RuCp(κ1(P),η2-PPh2CH2CH2CH*CH2)(CH3CN)]PF6 derived from the reaction of [RuCp(CH3CN)3]+ with PPh2CH2CH2CH*CH2 is a model compound for studying coupling reactions of olefins and acetylenes. In addition, [RuCp(CH3CN)3]+ is a valuable precursor for the synthesis of configurationally stable chiral three-legged piano-stool ruthenium complexes.
These are currently being intensively investigated as Lewis acid catalysts in asymmetric synthesis.
Received May 31, 2000. Accepted June 13, 2000 相似文献
4.
Robert H. Crabtree Jennifer M. Quirk Hugh Felkin Tauqir Fillebeen-Khan Claudine Pascard 《Journal of organometallic chemistry》1980,187(3):C32-C36
[Ir(cod)Cl]2 (cod = 1,5-cyclooctadiene) reacts with PMe2Ph in CH3CN to give the red cation [Ir(PMe2Ph)4]+. This complex in CH3CN reacts with H2 to give cis-[IrH2(PMe2Ph)4]+, but on reflux for 6 h in the absence of H2, it gives the first example of a cyclometallated PMe2Ph complex fac-[IrH(PMe2C6H4)(PMe2Ph)3]+, as shown by PMR spectroscopy and preliminary X-ray crystallographic data. 相似文献
5.
Stewart N. Anderson David L. Hughes Raymond L. Richards 《Transition Metal Chemistry》1985,10(1):29-30
Summary The compoundtrans-[MoCl2(PMe2Ph)4] has been prepared by the reduction of MoCl5 (by Mg) or of [MoCl3(PMe2Ph)3] (by LiBun) in the presence of PMe2Ph in tetrahydrofuran (THF). It has eff=2.84 B.M. and crystallises in space group P1 witha=11.591(3),b=12.931(3),c=12.703(3) Å, = 95.28(2), =105.97(2), =103.54(2)°. Refinement of the structure gave R=0.036. The Mo-Cl and Mo-P distances average 2.443(6) and 2.534(8) Å, respectively.Low-valent phosphine complexes of the Group VI metals continue to attract much attention because of their involvement in studies of the catalytic activation of dinitrogen(1), dihydrogen(2, 3), alkenes and alkynes(4). As a by-product during our studies of dinitrogen(1) and hydride(2) complexes of molybdenum and tungsten, we obtainedtrans-[MoCl2- (PMe2Ph)4] as yellow, paramagnetic crystals (eff= 2.84 B.M.). We first obtained the compound during the attempted synthesis ofcis-[Mo(N2)2(PMe2Ph)4] by reduction of MoCl5 with Mg in the presence of PMe2Ph (see Experimental). Upon identification of the compound we found that it could be readily synthesised by treatment of [MoCl3(PMe2Ph)3](5) with LiBun in THF in the presence of PMe2Ph (experimental).The complex was shown to have thetrans structure by x-ray analysis (Figure). Analogues oftrans-[MoCl2(PMe2Ph)4] have been prepared, namely [CrCl2(Me2PCH2CH2PMe2)2](6),trans- [MoCl2(PMe3)4](7), [WCl2(PMe2Ph)4](8) and [WCl2(PMe3)4](4), of which onlytrans-[MoCl2(PMe3)4] has been examined by X-rays(7). Its principal structural parametersi.e. d(Mo-Cl)= 2.420(6), d(Mo-P)av=2.496(3) Å(6) are close to those found here fortrans-[MoCl2(PMe2Ph)4]. 相似文献
6.
Ernesto Carmona Luis Sánchez Manuel L. Poveda Richard A. Jones John G. Hefner 《Polyhedron》1983,2(8):797-801
Direct reduction of WCl6 with PMe3 in toluene at 120°C in a sealed tube affords the complexes [WCl4(PMe3)x] (x = 2, 3). [WCl4(PMe3)3] abstracts oxygen from equimolar amounts of water in wet acetone or tetrahydrofuran to give [WOCl2(PMe3)3] in very high yields. This procedure has been successfully applied to the high yield synthesis of other known oxotungsten(IV) complexes, [WOCl2(PR3)3] (PR3 = PMe2Ph and PMePh2). Metathesis reactions of [WOCl2(PMe3)3] with NaX give [WOX2(PMe3)3] (X = NCO, NCS) and [WOX2(PMe3)] (X = Me2NCS2). The synthesis of the trimethylphosphite analogue, [WOCl2(P(OMe)3)3], is also described and the structures of the new complexes assigned on the basis of IR and 1H and 31P NMR spectroscopy. 相似文献
7.
Dr. Eszter M. Nagy Andrea Pettenuzzo Giulia Boscutti Prof. Dr. Luciano Marchiò Prof. Dr. Lisa Dalla Via Prof. Dr. Dolores Fregona 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(45):14464-14472
Hereby we present the synthesis of several ruthenium(II) and ruthenium(III) dithiocarbamato complexes. Proceeding from the Na[trans‐RuIII(dmso)2Cl4] ( 2 ) and cis‐[RuII(dmso)4Cl2] ( 3 ) precursors, the diamagnetic, mixed‐ligand [RuIIL2(dmso)2] complexes 4 and 5 , the paramagnetic, neutral [RuIIIL3] monomers 6 and 7 , the antiferromagnetically coupled ionic α‐[RuIII2L5]Cl complexes 8 and 9 as well as the β‐[RuIII2L5]Cl dinuclear species 10 and 11 (L=dimethyl‐ (DMDT) and pyrrolidinedithiocarbamate (PDT)) were obtained. All the compounds were fully characterised by elemental analysis as well as 1H NMR and FTIR spectroscopy. Moreover, for the first time the crystal structures of the dinuclear β‐[RuIII2(dmdt)5]BF4 ? CHCl3 ? CH3CN and of the novel [RuIIL2(dmso)2] complexes were also determined and discussed. For both the mono‐ and dinuclear RuII and RuIII complexes the central metal atoms assume a distorted octahedral geometry. Furthermore, in vitro cytotoxicity of the complexes has been evaluated on non‐small‐cell lung cancer (NSCLC) NCI‐H1975 cells. All the mono‐ and dinuclear RuIII dithiocarbamato compounds (i.e., complexes 6 – 10 ) show interesting cytotoxic activity, up to one order of magnitude higher with respect to cisplatin. Otherwise, no significant antiproliferative effect for either the precursors 2 and 3 or the RuII complexes 4 and 5 has been observed. 相似文献
8.
Reaction of 2-(phenylazo)pyridine (pap) with [Ru(PPh3)3X2] (X = Cl, Br) in dichloromethane solution affords [Ru(PPh3)2(pap)X2]. These diamagnetic complexes exhibit a weakdd transition and two intense MLCT transitions in the visible region. In dichloromethane solution they display a one-electron
reduction of pap near − 0.90 V vs SCE and a reversible ruthenium(II)-ruthenium(III) oxidation near 0.70 V vs SCE. The [RuIII(PPh3)2(pap)Cl2]+ complex cation, generated by coulometric oxidation of [Ru(PPh3)2(pap)Cl2], shows two intense LMCT transitions in the visible region. It oxidizes N,N-dimethylaniline and [RuII(bpy)2Cl2] (bpy = 2,2′-bipyridine) to produce N,N,N′,N′-tetramethylbenzidine and [RuIII(bpy)2Cl2]+ respectively. Reaction of [Ru(PPh3)2(pap)X2] with Ag+ in ethanol produces [Ru(PPh3)2(pap)(EtOH)2]2+ which upon further reaction with L (L = pap, bpy, acetylacetonate ion(acac−) and oxalate ion (ox2−)) gives complexes of type [Ru(PPh3)2(pap)(L)]n+ (n = 0, 1, 2). All these diamagnetic complexes show a weakdd transition and several intense MLCT transitions in the visible region. The ruthenium(II)-ruthenium(III) oxidation potential
decreases in the order (of L): pap > bpy > acac− > ox2−. Reductions of the coordinated pap and bpy are also observed. 相似文献
9.
T. Arthur R. Contreras G.A. Heath G. Hefter A.J. Lindsay D.J.A. Riach T.A. Stephenson 《Journal of organometallic chemistry》1979,179(4):C49-C54
Voltammetric studies reveal that, like [Ru2Cl4(PPh3)4(CO)], triply-bridged complexes [Ru2Cl4L5] (L = PClPh2, PMePh2, PEt2Ph) are reversibly oxidized to [Ru2Cl4L5]+. The mixed valence complexes [Ru2Cl5L3Y] (L = PPh3, P(tol)3; Y = CO, CS) undergo a corresponding reduction to [Ru2Cl5L3Y]?; whereas [Ru2Cl5L4] (L = PEt2Ph, As(tol)3) and [Ru2Cl6(AsPh3)3] are both reduced oxidised in reversible one-electron steps. For the bridging (RuCl3Ru)z+ moiety, the redox series z = 1, 2, 3, 4 is established. 相似文献
10.
The reduction of trans-RuCl2(PMe3)4 with Na/Hg and of trans-OsCl2(PMe3)4 with sodium in the presence of catalytic amounts of naphthalene gives the complexes RuH(η2-CH2PMe2)(PMe3)3 (III) and OsH(η2-CH2PMe2PMe2), (IV) in good yields. An equilibrium with the metal(0) isomers [M(PMe3)4] cannot be detected by NMR spectroscopy. III and IV react with dihalomethanes CH2X2 (X = Cl, Br, I) and CH3I to form mixtures of the dimethylphosphinomethanide complexes MX(η2-CH2PMe2)(PMe3)3 and the compounds MX2(PMe3)4. The reactions of III and IV with the Brönsted acids HCl, HBr, CF3CO2H and HC2Ph lead (with exception of M = Ru and X = C2Ph) to the complexes cis-MX2(PMe3)4. The hydrolysis of IV gives the hydrido(hydroxy) compound cis-OsH(OH)(PMe3)4, which has been characterized by 1H, 31P NMR and mass spectroscopy. The synthesis of the complex cis-Os(CH3)2(PMe3)4 is also described; the conversion into the ethylene(hydrido)metal cation [OsH(C2H4)(PMe3)4]+ failed. 相似文献
11.
UV photolysis of [CpFeII(CO)3]+ PF66? (I) or [CpFeII(η6-toluene)]+ PF6?? (II) in CH3CN in the presence of 1 mole of a ligand L gives the new air sensitive, red complexes [CpFeII(NCCH3)2L]+PF6? (III, L = PPh3; IV; L = CO; VIII, L = cyclohexene; IX, L = dimethylthiophene) and the known air stable complex [CpFeII(PMe3)2(NCMe)]+ PF6? (V). The last product is also obtained by photolysis in the presence of 2 or 3 moles of PMe3. In the presence of dppe, the known complex [CpFeII (dppe)(NCCH3)]+ (XI) is obtained. Complex III reacts with CO under mild conditions to give the known complex [CpFe(NCCH3)(PPh3)CO]+ PF6? (X). UV photolysis of I in CH3CN in the presence of 1-phenyl-3,4-dimethylphosphole (P) gives [CpFeIIP3]+ PF6? (XII); UV photolysis of II in CH2Cl2 in the presence of 3 moles of PMe3 or I mole of tripod (CH3C(CH2Ph2)3) provides an easy synthesis of the known complexes [CpFeII(PMe3)3]+ PF6? (VII) or [CpFeIIη3-tripod]+ PF6t- (XIII). Since I and II are easily accessible from ferrocene, these photolytic syntheses provide access to a wide range of piano-stool cyclopentadienyliron(II) cations in a 2-step process from ferrocene. 相似文献
12.
《Journal of Coordination Chemistry》2012,65(1):81-94
Abstract The triply halide-bridged binuclear complexes [Ru2Cl5(CO)(AsPh3)3] (AsPh3 = triphenylarsine), [Ru2Cl5(CO)(PPh3)2(AsPh3)] (PPh3 = triphenylphosphine), [Ru2Cl5(CO)(AsPh3)2(PPh3)], [Ru2 Br5(CO)(PPh3)3], [Ru2Cl5(CO)(P{p-tol}3)2(PPh3)] (P{p-tol}3 = tri-p-tolylphosphine) and [Ru2 Br2Cl3(PPh3)2(AsPh3)] were prepared from the precursor compounds ttt-[RuX2(CO)2(P)2] (X = Cl or Br) and [RuY3(P')2S]·S (Y = Cl or Br; P=PPh3, AsPh3 or P{p- tol}3 and P' = AsPh3 or PPh3; S=DMA or MeOH, where DMA = N,N'-dimethylacetamide). The molecular structures of the binuclear complexes [Ru2Cl5(CO)(AsPh3)3] (P21/c), [Ru2Br5(CO)(PPh3)3] (P21/c) and ttt-[RuCl2(CO)2(PPh3)2] (P1) were determined by X-ray diffraction methods. The complexes are always formed by two Ru atoms bridged through three halide anions, two of which are × type (from the RuII precursor) and the other is Y type (from the rutheniumIII precursor) confirming our previously suggested mechanism for obtaining this class of complexes. The RuII atom is also coordinated to a carbon monoxide molecule and two P ligands from the ttt-starting isomer whereas the RuIII atom is bonded to two non-bridging Y halides and one P' molecule. The presence of RuIII was confirmed by EPR data, a technique that was also useful to suggest the symmetry of the complexes. The absence of intervalence charge-transfer transitions (IT) in the near infrared spectrum confirms that the binuclear complexes have localized valence. The IR spectra of the complexes show; (CO) bands close to 1970 cm?1 and ν(Ru-Cl) or(Ru-Br) bands at about 230–380 cm?1 corresponding to halides at terminal or bridged positions. Two widely separated redox processes, RuII/RuII←RuII/RuIII→RuIII/RuIII, were observed by cyclic voltammetry and differential pulse voltammetry. 相似文献
13.
14.
《Journal of Coordination Chemistry》2012,65(3-4):367-377
Abstract New dinuclear asymmetric complexes of ruthenium and rhenium, of formula [(bpy)(CO)3 ReI(4,4′-bpy)RuII/III(NH3)5]3+/4+ have been prepared and characterized by spectroscopic and electrochemical techniques. In the mixed-valent species [ReI, RuIII], the back electron transfer reaction RuII → ReII, that occurs after light excitation, is predicted to be in the Marcus inverted region. This fact is consistent with the observed quenching of the luminiscence of the Re chromophore in [(bpy)(CO)3ReI(4,4′-bpy)RuIII(NH3)5]4+, when compared to the parent complex [(bpy)(CO)3ReI(4,4′-bpy)]+. A theoretical treatment due to Creutz, Newton and Sutin has been successfully applied to predict the electronic coupling element in the mixed-valent complex. 相似文献
15.
The complex [C5H5RhH(C2H4)PMe3]BF4 (I) reacts with NaF and NaCN by deprotonation to give C5H5Rh(PMe3)C2H4 but with NaCl, NaBr and NaI the ethylrhodium compounds C5H5RhC2H5(PMe3)X (II–IV) are obtained. The reactions of I with CO and PPri3 yield the BF4 salts of the cations [C5H5RhH(CO)PMe3]+ and [C5H5RhH(PPri3)PMe3]+ (V, VI), respectively, from which the uncharged complexes C5H5Rh(CO)PMe3 (VII) and C5H5Rh(PPRi3)PMe3 (VIII) are prepared. The carbonyl compound VII is also accessible either from C5H5Rh(CO)2 and PMe3 or from C5H5Rh(PMe3)2 and CO. The reaction of I with ethylene leads to the BF4 salt of the cation [C5H5RhC2H5(PMe3)C2H4]+ (X) which on treatment with PMe3 forms the complex [C5H5RhC2H5(PMe3)C2H4PMe3]BF4 (XI). The compound [C5H5RhH(C2H4)PPri3]BF4 (XII) reacts with NaI by insertion to yield C5H5RhC2H5(PPri3)I (XIII) whereas with PPri3 the salt [C5H5RhH(PPri3)2]BF4 (XIV) is produced. The bis(triisopropylphosphine) complex C5H5Rh(PPri3)2 (XVI) is obtained from XIV and NaH. 相似文献
16.
《Journal of Coordination Chemistry》2012,65(17):2893-2902
The complex [MnIV(napbh)2] (napbhH2 = N-(2-hydroxynaphthalen-1-yl)methylenebenzoylhydrazide) reacts with activated ruthenium(III) chloride in methanol in 1 : 1.2 molar ratio under reflux, giving heterobimetallic complexes, [MnIV(napbh)2RuIIICl3(H2O)] · [RuIII(napbhH)Cl2(H2O)] reacts with Mn(OAc)2·4H2O in methanol in 1 : 1.2 molar ratio under reflux to give [RuIII(napbhH)Cl2(H2O)MnII(OAc)2]. Replacement of aquo in these heterobimetallic complexes has been observed when the reactions are carried out in the presence of pyridine (py), 3-picoline (3-pic), or 4-picoline (4-pic). The molar conductances for these complexes in DMF indicates 1 : 1 electrolytes. Magnetic moment values suggest that these heterobimetallic complexes contain MnIV and RuIII or RuIII and MnII in the same structural unit. Electronic spectral studies suggest six coordinate metal ions. IR spectra reveal that the napbhH2 ligand coordinates in its enol form to MnIV and bridges to RuIII and in the keto form to RuIII and bridging to MnII. 相似文献
17.
M. Carmen Barral Dr. David Casanova Dr. Santiago Herrero Dr. Reyes Jiménez‐Aparicio Dr. M. Rosario Torres Dr. Francisco A. Urbanos Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(21):6203-6211
The magnetic behaviour of the compounds containing the [Ru2(DPhF)3(O2CMe)]+ ion (DPhF?=N,N′‐diphenylformamidinate) shows a strong dependence on the nature of the ligand bonded to the axial position. The new complexes [Ru2(DPhF)3(O2CMe)(OPMe3)][BF4]?0.5 CH2Cl2 ( 1 ? 0.5 CH2Cl2) and [Ru2(DPhF)3(O2CMe)(4‐pic)][BF4] ( 2 ) (4‐pic=4‐methylpyridine) clearly display this influence. Complex 1 ?0.5 CH2Cl2 shows a magnetic moment corresponding to a S=3/2 system affected by the common zero‐field splitting (ZFS) and a weak antiferromagnetic interaction, whereas complex 2 displays an intermediate behaviour between S=3/2 and S=1/2 systems. The experimental data of complex 1 are fitted with a model that considers the ZFS effect using the Hamiltonian ?D= S ? D ? S . The weak antiferromagnetic coupling is introduced as a perturbation, using the molecular field approximation. DFT calculations demonstrate that, in the [Ru2(O2CMe)(DPhF)3(L)]+ complexes, the energy level of the metal–metal molecular orbitals is strongly dependent on the nature of the axial ligand (L). This study reveals that the increase in the π‐acceptor character of L leads to a greater split between the π* and δ* HOMO orbitals. The influence of the axial ligand in the relative energy between the doublet and quartet states in this type of complexes was also analysed. This study was performed on the new complexes 1 ?0.5 CH2Cl2 and 2 . The previously isolated [Ru2(DPhF)3(O2CMe)(OH2)][BF4]?0.5 CH2Cl2 ( 3 ? 0.5 CH2Cl2) and [Ru2(DPhF)3(O2CMe)(CO)][BF4]?CH2Cl2 ( 4 ?CH2Cl2) complexes were also included in this study as representative examples of spin‐admixed and low‐spin configurations, respectively. The [Ru2(DPhF)3(O2CMe)]+ ( 5 ) unit was used as a reference compound. These theoretical studies are in accordance with the different magnetic behaviour experimentally observed. 相似文献
18.
Prof. Javier A. Cabeza Dr. Pablo García‐Álvarez Dr. Enrique Pérez‐Carreño Dr. Vanessa Pruneda 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(10):3426-3436
The methylation of the uncoordinated nitrogen atom of the cyclometalated triruthenium cluster complexes [Ru3(μ‐H)(μ‐κ2N1,C6‐2‐Mepyr)(CO)10] ( 1 ; 2‐MepyrH=2‐methylpyrimidine) and [Ru3(μ‐H)(μ‐κ2N1,C6‐4‐Mepyr)(CO)10] ( 9 ; 4‐MepyrH=4‐methylpyrimidine) gives two similar cationic complexes, [Ru3(μ‐H)(μ‐κ2N1,C6‐2,3‐Me2pyr)(CO)10]+( 2 +) and [Ru3(μ‐H)(μ‐κ2N1,C6‐3,4‐Me2pyr)(CO)10]+ ( 9 +), respectively, whose heterocyclic ligands belong to a novel type of N‐heterocyclic carbenes (NHCs) that have the Ccarbene atom in 6‐position of a pyrimidine framework. The position of the C‐methyl group in the ligands of complexes 2 + (on C2) and 9 + (on C4) is of key importance for the outcome of their reactions with K[N(SiMe3)2], K‐selectride, and cobaltocene. Although these reagents react with 2 + to give [Ru3(μ‐H)(μ‐κ2N1,C6‐2‐CH2‐3‐Mepyr)(CO)10] ( 3 ; deprotonation of the C2‐Me group), [Ru3(μ‐H)(μ3‐κ3N1,C5,C6‐4‐H‐2,3‐Me2pyr)(CO)9] ( 4 ; hydride addition at C4), and [Ru6(μ‐H)2{μ6‐κ6N1,N1′,C5,C5′,C6,C6′‐4,4′‐bis(2,3‐Me2pyr)}(CO)18] ( 5 ; reductive dimerization at C4), respectively, similar reactions with 9 + have only allowed the isolation of [Ru3(μ‐H)(μ3‐κ2N1,C6‐2‐H‐3,4‐Me2pyr)(CO)9] ( 11 ; hydride addition at C2). Compounds 3 and 11 also contain novel six‐membered ring NHC ligands. Theoretical studies have established that the deprotonation of 2 + and 9 + (that have ligand‐based LUMOs) are charge‐controlled processes and that both the composition of the LUMOs of these cationic complexes and the steric protection of their ligand ring atoms govern the regioselectivity of their nucleophilic addition and reduction reactions. 相似文献
19.
IR,Raman, and Surface‐enhanced Raman Spectroscopic Study on Triruthenium Dipyridylamide Diruthenium Nickel Dipyridylamide Family: Metal‐metal Bonding and Structures 下载免费PDF全文
Yu‐Chun Chiu Kuan‐Yi Ho a I‐Chia Chen Shao‐An Hua Ming‐Chuan Cheng Shie‐Ming Peng 《中国化学会会志》2014,61(12):1289-1296
We report the infrared, Raman, and surface‐enhanced Raman scattering (SERS) spectra of triruthenium dipyridylamido complexes and of diruthenium mixed nickel metal‐string complexes. From the results of analysis on the vibrational modes, we assigned their vibrational frequencies and structures. The infrared band at 323–326 cm?1 is assigned to the Ru3 asymmetric stretching mode for [Ru3(dpa)4Cl2]0–2+. In these complexes we observed no Raman band corresponding to the Ru3 symmetric stretching mode although this mode is expected to have substantial Raman intensity. There is no frequency shift in the Ru3 asymmetric stretching modes for the complexes with varied oxidational states. No splitting in Raman spectra for the pyridyl breathing line indicates similar bonding environment for both pyridyls in dpa– , thus a delocalized structure in the [Ru3]6–8+ unit is proposed. For Ru3(dpa)4(CN)2 complex series, we assign the infrared band at 302 cm?1 to the Ru3 asymmetric stretching mode and the weak Raman line at 285 cm?1 to the Ru3 symmetric stretching. Coordination to the strong axial ligand CN– weakens the Ru‐Ru bonding. For the diruthenium nickel complex [Ru2Ni(dpa)4Cl2]0–1+, the diruthenium stretching mode νRu‐Ru is assigned to the intense band at 327 and 333 cm?1 in the Raman spectra for the neutral and oxidized forms, respectively. This implies a strong Ru‐Ru metal‐metal bonding. 相似文献
20.
Ruthenium monoterpyridine complexes, [1]+ and [2]2+, with 2,6-bis(benzoxazol-2-yl)pyridine as an ancillary ligand, L, have been synthesized and characterized by UV–Vis, FT-IR and 1H NMR spectroscopic techniques. The formulations of the complexes were confirmed by the single crystal structure of their perchlorate salts. In both complexes, the RuII center is hexa-coordinated in a distorted geometry. In complex [1]+, the ancillary ligand L behaves as a bidentate ligand; in [2]2+, however, it binds the metal center as a tridentate ligand. The central pyridine nitrogen of terpyridine (Np,trpy) is in a cis position with respect to the central pyridine nitrogen of the ancillary ligand (Np,benz) in complex [1]+ and in a trans-position in complex [2]2+. The cis orientation of Np,trpy and Np,benz in complex [1]+ forces L to behave as bidentate. The quasi-reversible RuII/RuIII couple appears at 0.90 and 1.44 V versus SCE in the case of complex [1]+ and [2]2+, respectively. [1]+, in the presence of aqueous AgNO3, affords [2]2+ through an intramolecular dissociative interchange pathway. 相似文献