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1.
On the Reaction of Tellurium with Tungsten Halides: Synthesis and Crystal Structure of Te7WOCl5, a Compound with a Polymer Tellurium Cation The reaction of tellurium with WOCl4 in the presence of a large excess of WCl6 in a sealed evacuated glass ampoule at 150°C yields beside the main product Te8(WCl6)2 a small amount of Te7WOCl5. The crystal structure determination (orthorhombic space group Pcca, lattice parameters at 173 K: a = 2 596.5(9) pm, b = 810.0(3) pm, c = 775.7(2) pm) shows that Te7WOCl5 is built of one-dimensional band shaped polymeric tellurium cations, one-dimensional associated pyramidal WOCl4? anions and of isolated Cl? anions. Te7WOCl5 can thus be formulated as [Te72+]n [WOCl4?]n (Cl?). The structure is closely related but not isotypic to the bromine containing analogue Te7WOBr5. The difference between the two structures lies in different directions of the polar [WOX4?]n chains (X = Cl, Br). The strongly elongated thermal ellipsoid of one tellurium atom is shown to be caused by thermal vibration by determing the crystal structure of Te7WOCl5 at three different temperatures (223, 173 and 123 K). All displacement parameters of all atoms can be extrapolated to zero for 0 K.  相似文献   

2.
3.
《Polyhedron》1988,7(18):1767-1771
The complexes [MOCl2(dmpe)(PMe3)] and [MOCl2(dmpe)2]Cl (M = Mo, W; dmpe = Me2PCH2CH2PMe2) have been prepared by reaction of the oxo compounds [MOCl2(PMe3)3] with equivalent amounts of the dmpe ligand under appropriate conditions. The dark blue tungsten species [WOCl2(dmpe)(PMe3)] forms only slowly but reacts readily with more dmpe to afford [WOCl(dmpe)2]Cl. This prevents isolation of the former in a pure form. The related isocyanide derivatives [MOCl2(CNR)(PMe3)2], (M = Mo; R = CMe3 and C6H11; M = W, R = CMe3) have been obtained similarly by reaction of the [MOCl2(PMe3)3] complexes with the stoichiometric amount of the isocyanide ligand, but attempts to prepare the carbonyl analogues, [MOCl2(CO)(PMe3)2], have proved unsuccessful. The new compounds have been characterized by analytical and spectroscopic methods (IR, 1H, 13C and 13P NMR spectroscopy).  相似文献   

4.
Summary Reaction of MoCl5 or WCl6 with 1-methyl-1-phenylhydrazine or 1, 1-diphenylhydrazine hydrochloride results in the formation of MVI species [MCl4(NNRR)]. These react with tertiary phosphines PR3 to form MV species [MCl3(NNRR)(PR3) n ] (n=1 or 2).[MoCl3(NNMePh)(PMe3)2] can be reduced in the presence of PMe3 to the MoIV speciescis-mer-[MoCl2(NNMePh)(PMe3)3].  相似文献   

5.
Reaction of PhCONH2 with [WCl6] under reflux in benzene gives a near quantitative yield of [WOCl4(NCPh)] (1) which can be prepared directly by the reaction of PhCN and [WOCl4]. PhCONH2 reacts with [WOCl4] under reflux in benzene to give [WO2Cl2(NCPh)] (2) and with [NbCl5] under similar conditions to give [NbOCl3(NCPh)] (3). PhCONH2 and TiCl4 give [TiCl4(NH2COPh)2] (4). Reaction of the aroyl isocyanate PhCONCO with [WOCl4] gave [WOCl4(NCPh)] (1) and 4-Me3CPhCONCO and [WOCl4] gave [WOCl4(NCPhCMe3-4)] (5). PhCONCO reacts catalytically with [WOCl4] or [WOCl4(NCPh)] to give quantitative yields of PhCN. Similarly, 4-Me3CPhCONCO and 2-ClCPhCONCO react catalytically with [WOCl4] to give complete conversion to 4-Me3CPhCN and 2-ClCPhCN. DFT studies show structures and intermediates in support of a possible catalytic mechanism. This involves initial complexation followed by formation of a metallocycle from the WO bond and the CN bond of the isocyanate. Rearrangement and elimination of CO2 leads to an amidate complex that undergoes C-O bond scission and O migration to the W atom to give PhCN bound to the WOCl4 moiety in a cis arrangement. This complex is unstable with respect to dissociation which completes the catalytic cycle. The overall reaction WOCl4 + PhC(O)NCO → WOCl4·PhCN + CO2 is exothermic (ΔH = −20.7 kJ mol−1) and is favoured from free energy considerations (ΔG = −69.3 kJ mol−1).  相似文献   

6.
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   

7.
New Arsinidene-bridged Multinuclear Cluster Complexes of Ag and Au. The Crystal Structures of [Ag14(AsPh)6Cl2(PR3)8], (PR3 = PEt3, PMenPr2, PnPr3), [M4(As4Ph4)2(PR3)4], (M = Ag, PR3 = PEt3, PnPr3; M = Au, PR3 = PnPr3), [Au10(AsPh)4(PhAsSiMe3)2(PnPr3)6] The reaction of AgCl with PhAs(SiMe3)2 in presence of tertiary phosphines (PR3) leads to arsinidene-bridged silver clusters with the composition [Ag14(AsPh)6Cl2(PR3)8], (PR3 = PEt3 1 , PMenPr2 2 , PnPr3 3 ). Further it is possible to obtain the multinuclear complexes [Ag4(As4Ph4)2(PR3)4], (PR3 = PEt3 4 , PMenPr2 5 ). In analogy to that [PMe3AuCl] reacts with PhAs(SiMe3)2 and PnPr3 to form the compound [Au4(As4Ph4)2(PnPr3)4] 6 , which is isostructurell to 4 and 5 . The gold cluster [Au10(AsPh)4(PhAsSiMe3)2(PnPr3)6] 7 was obtained from the same solution. The structures were characterized by X-ray single crystal structure analysis. (Crystallographic data see “Inhaltsübersicht”)  相似文献   

8.
The addition of dichloromethane solutions of carbon diselenide to liquid ammonia containing suspensions of platinum bis-phosphine dichlorides [PtCl2(PRX)n] (n = 2, (PRX) = PMe3, PMe2Ph, PMePh2, and PPh3, n = 1, (PRX) = dppm, dppe, dppp, dppf) gives, after evaporation of the ammonia and extraction of the reaction residues with dichloromethane, the appropriate platinum bis-phosphine triselenocarbonate complexes in reasonable yields (40–60%).  相似文献   

9.
New Phosphido-bridged Multinuclear Complexes of Ag and Zn. The Crystal Structures of [Ag3(PPh2)3(PnBu2tBu)3], [Ag4(PPh2)4(PR3)4] (PR3 = PMenPr2, PnPr3), [Ag4(PPh2)4(PEt3)4]n, [Zn4(PPh2)4Cl4(PRR′2)2] (PRR′2 = PMenPr2, PnBu3, PEt2Ph), [Zn4(PhPSiMe3)4Cl4(C4H8O)2] and [Zn4(PtBu2)4Cl4] AgCl reacts with Ph2PSiMe3 in the presence of tertiary Phosphines (PnBu2tBu, PMenPr2, PnPr3 and PEt3) to form the multinuclear complexes [Ag3(PPh2)3(PnBu2tBu)3] 1 , [Ag4(PPh2)4(PR3)4] (PR3 = PMenPr2 2 , PnPr3 3 ) and [Ag4(PPh2)4(PEt3)4]n 4 . In analogy to that ZnCl2 reacts with Ph2PSiMe3 and PRR′2 to form the multinuclear complexes [Zn4(PPh2)4Cl4(PRR′2)2] (PRR′2 = PMenPr2 5 , PnBu3 6 , PEt2Ph 7 ). Further it was possible to obtain the compounds [Zn4(PhPSiMe3)4Cl4(C4H8O)2] 8 and [Zn4(PtBu2)4Cl4] 9 by reaction of ZnCl2 with PhP(SiMe3)2 and tBu2PSiMe3, respectively. The structures were characterized by X-ray single crystal structure analysis. Crystallographic data see “Inhaltsübersicht”.  相似文献   

10.
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   

11.
The two‐step one‐pot oxidative decarbonylation of [Fe2(S2C2H4)(CO)4(PMe3)2] ( 1 ) with [FeCp2]PF6, followed by addition of phosphane ligands, led to a series of diferrous dithiolato carbonyls 2 – 6 , containing three or four phosphane ligands. In situ measurements indicate efficient formation of 1 2+ as the initial intermediate of the oxidation of 1 , even when a deficiency of the oxidant was employed. Subsequent addition of PR3 gave rise to [Fe2(S2C2H4)(μ‐CO)(CO)3(PMe3)3]2+ ( 2 ) and [Fe2(S2C2H4)(μ‐CO)(CO)2(PMe3)2(PR3)2]2+ (R=Me 3 , OMe 4 ) as principal products. One terminal CO ligand in these complexes was readily substituted by MeCN, and [Fe2(S2C2H4)(μ‐CO)(CO)2(PMe3)3(MeCN)]2+ ( 5 ) and [Fe2(S2C2H4)(μ‐CO)(CO)(PMe3)4(MeCN)]2+ ( 6 ) were fully characterized. Relevant to the Hred state of the active site of Fe‐only hydrogenases, the unsymmetrical derivatives 5 and 6 feature a semibridging CO ligand trans to a labile coordination site.  相似文献   

12.
Summary Upon u.v. irradiation of [Fe(CO)4(PR 3 )] with HSiR3 (HSiR3 = HSiMePh2, PR3 = PPh3; HSiR3 = HSiMe2Cl, PR3 = PPh3 or PMe2Ph; HSiR3 = HSiMeCl2, PR3 = PPh3, PMePh2, PMe2Ph or PMe3; HSiR3 = HSiCl3, PR3 = PPh3, PMePh2, PMe2Ph, PMe3 or PBu 3 n ) the corresponding hydridosilyl complexes [Fe(CO)3H(PR3)SiR3] are formed. The complexes have themer configuration with acis disposition of the hydride and the silyl ligands. Prolonged irradiation with an excess of silane results in the formation of bis-silyl complexes [Fe(CO)3(PR3)(SiR3)2], if electron density at the metal is not too high. Thus, [Fe(CO)3H(PPh3)SiMePh2] and [Fe(CO)3-H(PMe2Ph)SiMe2Cl] can be obtained but not the corresponding bis-silyl complexes. Most bis-silyl complexes are obtained asmer-isomers with acis-arrangement of the silyl ligands. Only for [Fe(CO)3(PR3)(SiCl3)2] with small phosphine ligands (PR3 = PMe3 or PMe2Ph) is thefac-isomer formed.Part VII of this series, ref. (1).  相似文献   

13.
The complexes [Ir(cod)Ln]PF6(I, L = PPh3, PMePh2; n = 2. L = PMe2Ph; n = 3) react with HX to give [IrHX(cod)L2]PF6 (II, L = PMePh2 or PMe2Ph) or [IrHX2(cod)(PPh3)] (III). The intermediates [IrX(cod)L2] have, in two cases (L = PMePh2, X = I, Br), been directly isolated from the reaction mixtures at 0°C, and are also formed from I with KX (L = PPh3, X = Cl; L = PMePh2, X = Cl, Br, I); these intermediates protonate to give II (L = PMePh2), or an equimolar mixture of III and I (L = PPh3, X = Cl). Surprisingly, I2 reacts with I in MeOH to give III (L = PPh3). The stereochemistries of II and III were determined by < 1H NMR and especially by new methods using 13C NMR spectroscopy. The complexes I exhibit a Lewis acid reactivity pattern.  相似文献   

14.
The complexes C5H5Rh(PMe3)C2H3R′ (R′  H, Me, Ph) and C5H5Rh(PR3)C2H4(PR3  PMe2Ph, PPri3) are prepared by reaction of[PMe3(C2H3R/t')RhCl]2 or [PR3(C2H4)RhCl]2 and TlC5H5, respectively. They react with HBF4 in ether/propionic anhydride to form the BF4 salts of the hydrido(olefin)rhodium cations [C5H5RhH(C2H3R′)PR3]+(R  Me; R′  H, Me and R  Pri; R′  H). From C5H5Rh(PMe3)C2H3Ph and CF3COOH/NH4PF6 the η3-benzyl complex [C5H5Rh(PMe3)(η3-CH3CHC6H5)]PF6 is obtained. The reversibility of the protonation reactions is demonstrated by temperature-dependent NMR spectra and by deuteration experiments. The complexes C5H5Rh(PMe3)C2H3R′ (R′  H, Ph) and C5H5Rh(PMe2Ph)C2H4 react with CH3I in ether to give the salts [C5H5RhCH3(C2H3R′)PR3]I which in THF or CH3NO2 yield the neutral compounds C5H5RhCH3(PR3)I.  相似文献   

15.
Chalcogen Derivatives of the Halfsandwich Tungsten(V) Complexes Cp*WCl4 and Cp*WCl4(PMe3). X‐Ray Crystal Structure Analyses of anti ‐[Cp*W(Se)(μ‐Se)]2 and Cp*W(S)2(OMe) The chalcogenation of Cp*WCl4 ( 1 ) by E(SiMe3)2 (E = S, Se) and Te(SiMe2tBu)2 in chloroform solution leads to dimeric products of the type anti‐[Cp*W(E)(μ‐E)]2 (E = S ( 3 a ), Se ( 3 b ) and Te ( 3 c )). An X‐ray structure determination of 3 b indicates a centrosymmetric molecule containing a planar W(μ‐Se)2W ring, the W–W distance (297.9(1) pm) corresponds to a single bond. In the presence of air the two terminal chalcogenido ligands (E) in 3 a – c are stepwise replaced by oxido ligands (O) to give [Cp*W(O)(μ‐E)]2 (E = S ( 5 a ), Se ( 5 b ) and Te ( 5 c )) in quantitative yields. The reaction of Cp*WCl4 with H2S or ammonium polysulfide, (NH4)2Sx (x ∼ 10), leads to Cp*W(S)2Cl ( 6 a ); the corresponding methoxy derivative, Cp*W(S)2OCH3 ( 9 a ), has been characterized by an X‐ray structure analysis. On the other hand, the reaction of Cp*WCl4(PMe3) ( 2 ) with sodium tetrasulfide, Na2S4, in dimethylformamide solution gives a mixture of mononuclear Cp*W(S)(S2)Cl ( 8 a ), dinuclear [Cp*W(S)(μ‐S)]2 ( 3 a ) and a trinuclear side‐product of composition Cp*2W3S7 ( 13 a ). Terminal sulfido ligands are replaced by terminal oxido ligands in solution in the presence of oxygen. Thus, 6 a is stepwise converted into Cp*W(O)(S)Cl ( 10 a ) and CpW(O)2Cl ( 12 a ), whereas 8 a gives Cp*W(O)(S2)Cl ( 11 a ) and 13 a leads to Cp*2W3(O)S6 ( 14 a ). The disulfido complexes 8 a and 11 a are desulfurized by triphenylphosphane to give 6 a and 10 a . The new complexes have been characterized by their IR and NMR spectra and by mass spectrometry.  相似文献   

16.
Summary Binuclear PdII and PtII complexes of the type [M2Cl2(-Opy)2(PR3)2] [M = Pd or Pt; Opy = 2-OC5H4N (2-hydroxypyridinate ion); PR3 = PEt3, Pn-Bu3, PMe2Ph or PMePh2] were synthesized and characterized by elemental analysis, 1H- and 31P-n.m.r. spectroscopies. The Pd complexes exist in the sym trans form, whereas the corresponding Pt complexes were generated as different isomers.  相似文献   

17.
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   

18.
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   

19.
The reduction of [WCl4(PMe3)3] with dispersed sodium, under dinitrogen, gives cis-[W(N2)2(PMe3)4], while under ethylene trans-[W(C2H4)2(PMe3)4] is obtained. The ethylene complex can also be prepared by displacement of the dinitrogen molecules in cis-[W(N2)2(PMe3)4] by ethylene at room temperature and pressure. Interaction of cis-[M(N2)2(PMe3)4] complexes (M = Mo, W), with PMe3, under helium or argon, yields [M(N2)(PMe3)5]. The molybdenum complex crystallizes in the orthorhombic space group Pnma, with a 22.063(6), b 12.106(4), c 9.745(4) Å. The Mo—P distance trans to the dinitrogen ligand (2.483(7) Å) is slightly longer than the average of the other four Mo—P bonds (2.460(5) Å).  相似文献   

20.
Contributions to the Chemistry of Transition Metal Alkyl Compounds. XXXVII. About the Existence of 1-Norbornyl Compounds of Tungsten and Molybdenum Reactions of WCl6, WCl4, WO2Cl2, WOCl4, MoCl5, and MoO2(acac)2 with 1-Norbornyl lithium (1-NorLi1)) are described. From WCl6 and WCl4 [(1-Nor)2W]n is formed, whereas in dependence of the solvent WO2Cl2 and WOCl4 are transformed into the complexes Li2[1-NorWOCl4] · THF, Li[WOCl4], Li[WO2Cl2], and Li2[WO2Cl2]. MoCl5 and MoO2(acac)2 are reduced with formation of Li[MoCl5], Li[MoO2(acac)2] and Li2[MoO2(acac)2]. — Stable (1-Nor)4M-derivatives of molybdenum and tungsten, comparable those of 3d-metals (M = Ti? Co) seem not to exist.  相似文献   

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