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1.
Reactions of NaER (E = Se, Te; R = Ph, substituted Ph or 2-pyridyl) with a number of mono- and bi-nuclear palladium and platinum complexes have been investigated. Complexes of the type [M(Sepy)2], [M(ER)2(PR3)2], [M2Cl2(μ-ER)2(PR3)2] and [M2Cl2(μ-Cl)(μ-ER)(PR3)2] (M = Pd, Pt) were isolated. They were characterized by elemental analysis, NMR (1H, 13C, 31P, 77Se, 125Te, 195Pt) data and in a few cases by X-ray diffraction studies. The [M(Sepy)2(PPh3)2] dissociates into PPh3 and [M(Sepy)(η2-Sepy)(PPh3)] in solution. 2-Selenopyridine in its complexes acts in a monodentate (bonding through selenium) as well as in chelating (Se?N) or bridging fashion. The mononuclear complexes [M(ER)2(PR3)2] are useful precursors for stepwise synthesis of cationic bi- and tri-nuclear derivatives.  相似文献   

2.
Cyclic voltammetry has been employed to study the diffusive, irreversible platinum(II) → platinum(0) reduction of three sets of structurally related complexes: cis-[PtCl2P{p-C6H4X}3)2] (X = H, CH3, Cl, F, OCH3, N(CH3)2); cis-[PtCl2(PPh2R)2] (R = CH3, n-C3H7, n-C5H11, n-C6H13, n-C12H25) and cis-[PtCl2(PR3)2] (R = CH3, C2H5, CH2ch2CN). Relationships between the peak potentials for the Pt(II) → Pt(0) reduction and thermodynamic parameters which measure the electronic properties of the ligands are shown to exist for complexes of P{p-C6H4X}3 ligands, implying a thermodynamic origin for the sensitivity of the peak potentials to structural change. Complexes of both P{p-C6H4X}3 and PPh2R ligands show correlations between peak potentials for reduction and the 31P{1H} NMR spectroscopic parameter, 1J(195Pt, 31P). Correlations with values of δ(31P) exist in both cases, but a correlation with the coordination chemical shift, Δδ(31P), exists for complexes of PPh2R, and not for complexes of P{C6H4X}3. Complexes of PR3 ligands show no correlation between the peak potentials measured for the Pt(II) → Pt(0) reduction and electronic or spectroscopic parameters, except possibly 1J(195Pt, 31P).  相似文献   

3.
The 1H and 31P NMR spectra of (η3-allyl)Pt(PR3)Cl] (PR3 = PMe3, PCy3, P-t-Bu3, P-n-Bu3, PPh3, PPh2Me, PPhMe2 and P(p-Tol)3) complexes in chloroform have been studied. The results suggest that there is bonding interaction between the phosphine and the allyl group via central metal atom.  相似文献   

4.
Mono-cyclopentadienyl complexes CpVX2(PR3)2 and Cp′VX2 (PR3)2 (Cp = η5- C5H5; Cp′ = η5-C5H4Me; R = Me, Et; X = Cl, Br) have been prepared by reaction of VX3(PR3)2 with CpM (M = Na, T1, SnBun3, 1/2 Mg) or Cp′Na. Attempts to prepare analogous complexes with other phosphine ligands, PPh3, PPh2 Me, PPhMe2, Pcy3, DMPE and DPPE failed. Reduction of CpVCl2(PEt3)2 with zinc or aluminium under CO (1 bar) offers a simple method for the preparation of CpV(CO)3(PEt3). The crystal structure of the trimethylphosphine complex CpVCl2(PMe3)2 is reported.  相似文献   

5.
The compounds [Pt(C2H4)2(PR3)] [PR3 = P-tBu2Me, P(C6H11)3, PPh3] react dimethyldivinylsilane or dimethyldivinyltin to give chelate complexes [Pt{(CH2CH)2MMe2} (PR3)] (M = Si or Sn). allyltrimethyltin reacts with various diethylene (tertiary phosphine)platinum compounds with cleavage of the allyl group to afford complexes [Pt(SnMe3)(η3-C3H5)(PR2)]. The NMR spectra (13C, 1H and 31P) of the new compounds have been recorded, and the data are discussed in terms of the structures proposed.  相似文献   

6.
The reaction of [Pt2X2(-Cl)2(PR3)2] with NaSpy or NaSepy gave complexes of the type [PtX(Epy)(PR3)]n (X=Cl or Ar; E=S or Se; PR3=PEt3, PMe2Ph, PMePh2 or PPh3; n=1 or 2) which were characterized by elemental analysis and by 1H, 31P{1H}, 195Pt{1H} n.m.r. spectroscopy. When X=Cl a dynamic equilibrium between [Pt2Cl2(-Spy)2(PR3)2] and [PtCl(k-S,N-Spy)(PR3)] species exists in CHCl3 solution. The aryl derivatives, X=Ar, exist exclusively as dimers (n=2) with predominantly SN bridging. The [Pt(Spy)2 (PPh3)2] complex, prepared by reacting [PtCl2 (PPh3)2] with NaSpy, dissociates in CHCl3 to [Pt(k-S,N-Spy) (Spy)(PPh3)] and PPh3 at room temperature.  相似文献   

7.
On the Reactivity of Alkylthio Bridged 44 CVE Triangular Platinum Clusters: Reactions with Bidentate Phosphine Ligands The 44 cve (cluster valence electrons) triangular platinum clusters [{Pt(PR3)}3(μ‐SMe)3]Cl (PR3 = PPh3, 2a ; P(4‐FC6H4)3, 2b ; P(n‐Bu)3, 2c ) were found to react with PPh2CH2PPh2 (dppm) in a degradation reaction yielding dinuclear platinum(I) complexes [{Pt(PR3)}2(μ‐SMe)(μ‐dppm)]Cl (PR3 = PPh3, 3a ; P(4‐FC6H4)3, 3b ; P(n‐Bu)3; 3e ) and the platinum(II) complex [Pt(SMe)2(dppm)] ( 4 ), whereas the addition of PPh2CH2CH2PPh2 (dppe) to cluster 2a afforded a mixture of degradation products, among others the complexes [Pt(dppe)2] and [Pt(dppe)2]Cl2. On the other hand, the treatment of cluster 2a with PPh2CH2CH2CH2PPh2 (dppp) ended up in the formation of the cationic complex [{Pt(dppp)}2(μ‐SMe)2]Cl2 ( 5 ). Furthermore, the terminal PPh3 ligands in complex 3a proved to be subject to substitution by the stronger donating monodentate phosphine ligands PMePh2 and PMe2Ph yielding the analogous complexes [{Pt(PR3)}2(μ‐SMe)(μ‐dppm)]Cl (PR3 = PMePh2, 3c ; PMe2Ph, 3d ). NMR investigations on complexes 3 showed an inverse correlation of Tolmans electronic parameter ν with the coupling constants 1J(Pt,P) and 1J(Pt,Pt). All compounds were fully characterized by means of NMR and IR spectroscopy. X‐ray diffraction analyses were performed for the complexes [{Pt{P(4‐FC6H4)3}}2(μ‐SMe)(μ‐dppm)]Cl ( 3b ), [Pt(SMe)2(dppm)] ( 4 ), and [{Pt(dppp)}2(μ‐SMe)2]Cl2 ( 5 ).  相似文献   

8.
The reactions of the tungsten(I) complex of picolinic acid [W(CO)3(pic)]n with certain monodentate tertiary phosphines affords a convenient route to complexes of the types W(CO)3(PR3)3 and HW(CO)2(PR3)2(pic). The latter hydrido complexes of tungsten(II) have been characterized by infrared and NMR spectroscopy. The reactions of Re2(CO)10 with picolinic acid have also been investigated and the new series of rhenium(I) derivatives of the types Re(CO)3(L)(pic), where L = py, 4-Ph-py, PPh3 or dppe, and Re(CO)2(L')2(pic), where L' = PPh3 or 12dppe, have been isolated and characterized.  相似文献   

9.
Syntheses of the complexes trans-[PtCl2(PR3)Mo2(CO)45-C5H5)2(tBuCP)], (PR3=PEt3, PPr3, PBu3, PPh2Me, PPhMe2) trans-[PdCl2(PBu3)Mo2(CO)45-C5H5)2(tBuCP)], and trans[RhCl{(PF2NMe)2CO}Mo2(CO)45-C5H5)2(tBuCP)] are described and their 31P NMR spectra presented and discussed.  相似文献   

10.
The dark red octahydride complex of dirhenium, Re2H8(PPh3)4, undergoes a reversible one-electron oxidation to the blue mono-cation [Re2H8(PPh3)4]+ (Ebuit;12 ?0.24 V vs. SCE by cyclic voltammetry). The X-band ESR spectrum of a dichloromethane glass (?160°C) containing the monocation is in accord with the HOMO being a delocalized metal-based orbital. Treatment of the heptahydrides ReH7(PR3)2 (PR3 = PPh3 or PEtPh2) with C6H11NC or Me3CNC in the presence of KPF6 leads to the elimination of hydrogen and the formation of [Re(CNR)4(PR3)2]PF6. Electrochemical oxidation of ReH5(PPh3)2L (L = PPh3, PEt2Ph, pyridine, piperidine or cyclohexylamine) activities these molecules to attack by RNC to afford rhenium(I) species  相似文献   

11.
Abstract

The immobilization of the dinuclear platinum(II) sulfido complex [Pt2(μ-S)2 (PPh3)4] on solid supports has been investigated. Reaction with haloalkyl functionalized polymers [Merrifield's resin (chloromethylated polystyrene), chloropropyl silica, chloropropyl controlled pore glass, and bromopropyl polysiloxane] gives complexes immobilized through alkylation of one of the sulfide ligands, forming a μ-thiolate ligand acting as an anchor to the polymer support, akin to well-established reactions of [Pt2(μ-S)2(PPh3)4] with molecular alkylating agents. The model complex [Pt2(μ-S)(μ-SCH2SiMe3)(PPh3)4]PF6 was prepared as the first molecular silicon-containing derivative of [Pt2(μ-S)2(PPh3)4] and was fully characterized by NMR spectroscopy, electrospray ionization-mass spectrometry, and single-crystal X-ray diffraction. Immobilization of [Pt2(μ-S)2(PPh3)4] by phosphine exchange reactions was also achieved using commercial polystyrene-grafted triphenylphosphine or a new immobilized phosphine [derived by sequential functionalization of Merrifield's resin with a polyether amine and then Ph2PCH2OH].  相似文献   

12.
Trimethylamine N-oxide (TMNO)-initiated decarbonylations of Mo(CO)6 followed by phosphine additions yield the complexes Mo(CO)5(Ph2PCH2PPh2), which consists of a unidentate diphosphine, and the dinuclear phosphine-bridged complexes Mo2(CO)10(μ-Ph2P(CH2)nPPh2) (where n = 2, 3) at ambient temperatures. The IR and NMR (1H and 31P) spectroscopic and structural properties of these complexes are presented and discussed. Some thermal analytical data are summarised.  相似文献   

13.
[(PPh3)3(PPh2)2Pd3Cl] Cl, benzene and aniline hydrochloride were isolated as products of the reactions of (PPh3)2PdCl2]2 or [(PPh3)PdCl2]2 with H2 in organic amines (Am). Similar products were obtained when (Ph3P)2Pd(Ph)Br was treated with H23 Both in amines and aromatic solvents. The reaction between H2 and [(PBu3)PdCl2]2 resulted in the formation of [(PBu3(PBu2)PdCl2 ·. 2 Am The kinetic data for H2 absorption by solutions of palladium(II) complexes are consistent with the heterolytic mechanism of cleavage fo hte HH bond in the coordination sphere of palladium(II); the function of the H+ acceptor being performed by the bases (e.g. Am or Ph). The reaction between the palladium complexes and H2 is autocatalytic. Reduction of the initial PdII complexes leads to lower oxidation state palladium complexes, which catalyse the reduction of PdII complexes. In the coordination sphere of the lower oxidation state palladium complexes, the oxidative addition of PR3 to Pd takes place with formation of compounds containing a Pd-R bond. It is the reaction between these complexes and H2 that yields palladium compounds with PR2 ligands.  相似文献   

14.
Platinum(II) hydridotin complexes containing bulky phosphine ligands, trans-Pt(H)L2(SnR3) have been prepared from: (i) the equimolar reaction between corresponding platinum(II) dihydride complexes and HSnR3 (Cy = cyclohexyl), P-i-Pr3, P-t-BuPh2, P-t-Bu2Me; R = Ph), (ii) the oxidative addition of the corresponding zerovalent complexes, Pt0L2, with HSnR3 (L = P-i-Pr3, P-t-BuPh2; R = Ph), (iii) the reaction of the corresponding platinum(II) dihydride complexes with ClSnR3 in the presence of pyridine in benzene (L = P-i-Pr3, P-t-BuPh2; R = CH3, n-Bu), (iv) the sodium borohydride reduction of the corresponding hydridochloride complexes Pt(H)Cl(PR3)2 with ClSnR3 in THF (L = PCy3; R = Ph), these compounds have been characterized by their elemental analysis, infrared, 1H and 31P NMR spectral data.  相似文献   

15.
《Polyhedron》1999,18(21):2729-2736
A family of three mixed-ligand osmium complexes of type [Os(PPh3)2(N-N)Br2], where N-N=2,2′-bipyridine (bpy), 4,4′-dimethyl-2,2′-bipyridine (Me2bpy) and 1,10-phenanthroline (phen), have been synthesized and characterized. The complexes are diamagnetic (low-spin d6, S=0) and in dichloromethane solution they show intense MLCT transitions in the visible region. The two bromide ligands have been replaced from the coordination sphere of [Os(PPh3)2(phen)Br2] under mild conditions by a series of anionic ligands L (where L=quinolin-8-olate (q), picolinate (pic), oxalate (Hox) and 1-nitroso-2-naphtholate (nn)) to afford complexes of type [Os(PPh3)2(phen)(L)]+, which have been isolated and characterized as the perchlorate salt. The structure of the [Os(PPh3)2(phen)(pic)]ClO4 complex has been determined by X-ray crystallography. The PPh3 ligands occupy trans positions and the picolinate anion is coordinated to osmium as a bidentate N,O-donor forming a five-membered chelate ring. The [Os(PPh3)2(phen)(L)]+ complexes are diamagnetic and show multiple MLCT transitions in the visible region. The [Os(PPh3)2(N-N)Br2] complexes show an osmium(II)–osmium(III) oxidation (−0.02 to 0.12 V vs. SCE) followed by an osmium(III)–osmium(IV) oxidation (1.31 to 1.43 V vs. SCE). The [Os(PPh3)2(phen)(L)]+ complexes display the osmium (II)–osmium (III) oxidation (0.26 to 0.84 V vs. SCE) and one reduction of phen (−1.50 to −1.79 V vs. SCE). The osmium (III)–osmium (IV) oxidation has been observed only for the L=q and L=Hox complexes at 1.38 V vs. SCE and 1.42 V vs. SCE respectively. The osmium(III) species, viz. [OsIII(PPh3)2(N-N)Br2]+ and [OsIII(PPh3)2(phen)(L)]2+, have been generated both chemically and electrochemically and characterized in solution by electronic spectroscopy and cyclic voltammetry.  相似文献   

16.
As for [RuCl2(PPh33], carbonylation of [RuCl2(PR3)3] [PR3 = P(p-tolyl)3, PEtPh2) in N,N 1-dimethylformamide (dmf) gives [Ru(CO)Cl2 (dmf) (PR3)2] (II). For PR3 = PEtPh2, rearrangement of (II) in various solvents gives inseparable mixtures (31P evidence) but for PR3 = P(p-tolyl)3 [Ru2(CO)2Cl4-{P(p-tolyl)3}3]is obtained. Reaction of [Ru(CO)Cl2 (dmf) - {P(p-tolyl)3}2] with [RuCI2{(P(p-tolyl)3}3] (1:1 mol ratio) gives [Ru2 (CO) Cl4 {P (p-tolyl)3}4] whereas reaction of [Ru (CO) Cl2 (dmf) - (PPh32] with (Rul2 {P (p-tolyl)3}3] gives [Ru2(CO)Cl4 (PPh3)2] - {P(p-tolyl)3}2] - Reaction of [RuCl2 {P(p-tolyl)3}3] with CS2 gives the related [Ru2Cl4(CS) {P(p-tolyl)3}4] and [{RuCl2(CS)}P(p-tolyl)3{2}2] whereas [RuCl2(PEtPh2)3] and CS2 produce [RuCl2(S2CPEtPh2) (PEtPh2)2]CS2 and [Ru2Cl4(CS)2(PEtph2)3].  相似文献   

17.
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   

18.
The redox reaction of bis(2-benzamidophenyl) disulfide (H2L-LH2) with [Pd(PPh3)4] in a 1:1 ratio gave mononuclear and dinuclear palladium(II) complexes with 2-benzamidobenzenethiolate (H2L), [Pd(H2L-S)2(PPh3)2] (1) and [Pd2(H2L-S)2 (μ-H2L-S)2(PPh3)2] (2). A similar reaction with [Pt(PPh3)4] produced only the corresponding mononuclear platinum(II) complex, [Pt(H2L-S)2(PPh3)2] (3). Treatment of these complexes with KOH led to the formation of cyclometallated palladium(II) and platinum(II) complexes, [Pd(L-C,N,S)(PPh3)] ([4]) and [Pt(L-C,N,S) (PPh3)] ([5]). The molecular structures of 2, 3 and [4] were determined by X-ray crystallography.  相似文献   

19.
CO2, COS, and SCNPh react under very mild conditions with the copper(I)-tetrahydroborate complexes [(PR3)2Cu(η2-BH4)] (R = Ph, Cy); CO2 and COS give the complexes [(PR3)2Cu(η2-O2CH)] and [(PR3)2Cu(η2-OSCH)] respectively, whereas SCNPh gives the η2-dithiocarbamate complexes [(PR3)2Cu-(η2-S2CNHPh)]. Addition of PPh3 under CO2 to solutions of [(PPh3)2Cu-(η2-BH4)] gives [(PPh3)3Cu(η1-O2CH)] while addition of PPh3 and NBu4ClO4 under CO2 gives [(PPh3)3Cu(η-O2CH)Cu(PPh3)3] ClO4.  相似文献   

20.
Compounds of the type [XM(CO)2(ν-allyl)L2] (where X = Cl and Br; M = Mo and W; L2 = Ph2PCH2PPh2 and Ph2 PCH2CH2PPh2) have been prepard from the corersponding MeCN complexes. The spectral properties of these compounds and the effects of chelate rign size on 31P coordination shifts and J(183W—31P) have been investigated.  相似文献   

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