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1.
An efficient route to the novel tridentate phosphine ligands RP[CH2CH2CH2P(OR′)2]2 (I: R = Ph; R′ = i-Pr; II: R = Cy; R′ = i-Pr; III: R = Ph; R′ = Me and IV: R = Cy; R′ = Me) has been developed. The corresponding ruthenium and iron dicarbonyl complexes M(triphos)(CO)2 (1: M = Ru; triphos = I; 2: M = Ru; triphos = II; 3: M = Ru; triphos = III; 4: M = Ru; triphos = IV; 5: M = Fe; triphos = I; 6: M = Fe; triphos = II; 7: M = Fe; triphos = III and 8: M = Fe; triphos = IV) have been prepared and fully characterized. The structures of 1, 3 and 5 have been established by X-ray diffraction studies. The oxidative addition of MeI to 1-8 produces a mixture of the corresponding isomeric octahedral cationic complexes mer,trans-(13a-20a) and mer,cis-[M(Me)(triphos)(CO)2]I (13b-20b) (M = Ru, Fe; triphos = I-IV). The structures of 13a and 20a (as the tetraphenylborate salt (21)) have been verified by X-ray diffraction studies. The oxidative addition of other alkyl iodides (EtI, i-PrI and n-PrI) to 1-8 did not afford the corresponding alkyl metal complexes and rather the cationic octahedral iodo complexes mer,cis-[M(I)(triphos)(CO)2]I (22-29) (M = Ru, Fe; triphos = I-IV) were produced. Complexes 22-29 could also be obtained by the addition of a stoichiometric amount of I2 to 1-8. The structure of 22 has been verified by an X-ray diffraction study. Reaction of 13a/b-20a/b with CO afforded the acetyl complexes mer,trans-[M(COMe)(triphos)(CO)2]I, 30-37, respectively (M = Ru, Fe; triphos = I-IV). The ruthenium acetyl complexes 30-33 reacted slowly with 2-tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2-diazaphosphorine (BEMP) even in boiling acetonitrile. Under the same conditions, the deprotonation reactions of the iron acetyl complexes 34-37 were completed within 24-40 h to afford the corresponding zero valent complexes 5-8. It was not possible to observe the intermediate ketene complexes. Tracing of the released ketene was attempted by deprotonation studies on the labelled species mer,trans-[Fe(COCD3)(triphos)(CO)2]I (38) and mer,trans-[Fe(13COMe)(triphos)(CO)2]I (39).  相似文献   

2.
Three divalent copper coordination polymers containing aromatic dicarboxylate ligands and the long-spanning tethering imine bis(4-pyridylmethyl)piperazine (bpmp) have been prepared and structurally characterized. The length of the dicarboxylate pendant arms, carboxylate binding mode, and the inclusion of anionic components play a synergistic role in structure direction in this system. {[Cu(ip)(bpmp)(H2O)]·5H2O}n (ip = isophthalate, 1) displays neutral (4,4) rectangular coordination polymer grids that stack in an ABCD repeat pattern. Use of the longer pendant arm dicarboxylate 1,3-phenylenediacetate (phda) resulted in {[Cu2(phda)2(bpmp)]·H2O}n (2), a 3-D network coordination polymer with primitive cubic topology that features strongly antiferromagnetically coupled (J = −331(1) cm−1) {Cu2(CO2)4} paddlewheel units. In the presence of excess nitrate ions, {[Cu(phda)(Hbpmp)](NO3)·3H2O}n (3) was isolated instead of 2; 3 manifests cationic 2-D coordination polymer layers built from weakly antiferromagnetically coupled (J = −2.43(1) cm−1) {Cu2O2} dimers linked through phda and protonated bpmp ligands. The striking difference in magnetic properties is ascribed to the equatorial–equatorial versus axial–equatorial bridging of copper coordination spheres in 2 and 3, respectively.  相似文献   

3.
A series of 2,6-bis(imino)pyridyl iron(II) and cobalt(II) complexes [2,6-(ArNCMe)2C5H3N]MCl2 (Ar = 2,6-i-Pr2C6H3, M = Fe: 3a, M = Co: 4a; Ar = 2,4,6-i-Pr3C6H2, M = Fe: 3b, M = Co: 4b; Ar = 2,6-i-Pr2-4-BrC6H2, M = Fe: 3c, M = Co: 4c; Ar = 2,4-i-Pr2-6-BrC6H2, M = Fe: 3d, M = Co: 4d) has been synthesized, characterized, and investigated as precatalysts for the polymerization of ethylene in the presence of modified methylaluminoxane (MMAO). The substituents of pyridinebisimine ligands and their positions located significantly influence catalyst activity and polymer property. It is found that the catalytic activities of the iron complexes/MMAO systems are mainly dominated by electronical effect, while those of the cobalt complexes/MMAO systems are primarily controlled by hindering effect.  相似文献   

4.
Hydrothermal synthesis has afforded a pair of isostructural acentric three-dimensional coordination polymers {[M2(malonate)2(dpa)(H2O)2] · 2H2O}n (M = Co, 1; M = Ni, 2; dpa = 4,4′-dipyridylamine), which were structurally characterized via single-crystal X-ray diffraction and spectroscopically and thermally analyzed. Both materials exhibit exotridentate malonate ligands conjoining metal atoms into grid-like [M(malonate)(H2O)]n layers; in turn, these are connected into 3-D sqp lattices (4466 topology) through tethering dpa ligands. The central kink and inter-ring torsion within the dpa ligands enforces the acentric Aba2 space group of crystals of 1 and 2. Antiferromagnetic coupling (g = 2.08(2), J = –1.05(8) cm−3) was observed within the malonate-bridged layer motifs within the cobalt derivative 1. In contrast, the nickel congener 2 exhibited ferromagnetic coupling (g = 2.201(1), J = 0.289(1) cm−3).  相似文献   

5.
Treatment of either RuHCl(CO)(PPh3)3 or MPhCl(CO)(PPh3)2 with HSiMeCl2 produces the five-coordinate dichloro(methyl)silyl complexes, M(SiMeCl2)Cl(CO)(PPh3)2 (1a, M = Ru; 1b, M = Os). 1a and 1b react readily with hydroxide ions and with ethanol to give M(SiMe[OH]2)Cl(CO)(PPh3)2 (2a, M = Ru; 2b, M = Os) and M(SiMe[OEt]2)Cl(CO)(PPh3)2 (3a, M = Ru; 3b, M = Os), respectively. 3b adds CO to form the six-coordinate complex, Os(SiMe[OEt]2)Cl(CO)2(PPh3)2 (4b) and crystal structure determinations of 3b and 4b reveal very different Os-Si distances in the five-coordinate complex (2.3196(11) Å) and in the six-coordinate complex (2.4901(8) Å). Reaction between 1a and 1b and 8-aminoquinoline results in displacement of a triphenylphosphine ligand and formation of the six-coordinate chelate complexes M(SiMeCl2)Cl(CO)(PPh3)(κ2(N,N)-NC9H6NH2-8) (5a, M = Ru; 5b, M = Os), respectively. Crystal structure determination of 5a reveals that the amino function of the chelating 8-aminoquinoline ligand is located adjacent to the reactive Si-Cl bonds of the dichloro(methyl)silyl ligand but no reaction between these functions is observed. However, 5a and 5b react readily with ethanol to give ultimately M(SiMe[OEt]2)Cl(CO)(PPh3)(κ2(N,N-NC9H6NH2-8) (6a, M = Ru; 6b, M = Os). In the case of ruthenium only, the intermediate ethanolysis product Ru(SiMeCl[OEt])Cl(CO)(PPh3)(κ2(N,N-NC9H6NH2-8) (6c) was also isolated. The crystal structure of 6c was determined. Reaction between 1b and excess 2-aminopyridine results in condensation between the Si-Cl bonds and the N-H bonds with formation of a novel tridentate “NSiN” ligand in the complex Os(κ3(Si,N,N)-SiMe[NH(2-C5H4N)]2)Cl(CO)(PPh3) (7b). Crystal structure determination of 7b shows that the “NSiN” ligand coordinates to osmium with a “facial” arrangement and with chloride trans to the silyl ligand.  相似文献   

6.
The salts [S(NMe2)3][MF6] (M = Nb, 2a; M = Ta, 2b) and [S(NMe2)3][M2F11] (M = Nb, 2c; M = Ta, 2d) have been prepared by reacting MF5 (M = Nb, 1a; M = Ta, 1b) with [S(NMe2)3][SiMe3F2] (TASF reagent) in the appropriate molar ratio. The solid state structure of 2b has been ascertained by X-ray diffraction. The 1:1 molar ratio reactions of 1a with a variety of organic compounds (L) give the neutral adducts NbF5L [L = Me2CO, 3a; L = MeCHO, 3b; L = Ph2CO, 3c; L = tetrahydrofuran (thf), 3d; L = MeOH, 3e; L = EtOH, 3f; L = HOCH2CH2OMe, 3g; L = Ph3PO, 3h; L = NCMe, 3i] in good yields. The complexes MF5L [M = Nb, L = HCONMe2, 3j; M = Nb, L = (NMe2)2CO, 3k; M = Ta, L = (NMe2)2CO, 3l; M = Nb, L = OC(Me)CHCMe2, 3m] have been detected in solution in admixture with other unidentified products, upon 2:1 molar reaction of 1 with the appropriate reagent L. The ionic complexes [NbF4(tht)2][NbF6], 4a, and [NbF4(tht)2][Nb2F11], 4b, have been obtained by combination of tetrahydrothiophene (tht) and 1a, in 1:1 and 2:3 molar ratios, respectively. The treatment of 1 with a two-fold excess of L leads to the species [MF4L4][MF6] [M = Nb, L = HCONMe2, 5a; M = Ta, L = HCONMe2, 5b; M = Nb, L = thf, 5c; M = Ta, L = thf, 5d; M = Nb, L = OEt2, 5e]. The new complexes have been fully characterised by NMR spectroscopy. Moreover, the revised 19F NMR features of the known compounds MF5L [M = Ta, L = Me2CO, 3n; M = Ta, L = Ph2CO, 3o; M = Ta, L = MePhCO, 3p; M = Ta, L = thf, 3q; M = Nb, L = CH3CO2H, 3r; M = Nb, L = CH2ClCO2H, 3s; M = Ta, L = CH2ClCO2H, 3t], TaF4(acac), TaF4(Me-acac) and [TaF(Me-acac)3][TaF6] (Me-acac = methylacetylacetonato anion) are reported.  相似文献   

7.
Mononuclear compounds M(CO)23-C3H5)(en)(X) (X = Br, M = Mo(1), W(2); X = N3, M = Mo(3), W(4); X = CN, M = Mo(5), W(6)) and cyanide-bridged bimetallic compounds [(en)(η3-C3H5)(CO)2M(μ-CN)M(CO)23-C3H5)(en)]Br (M = Mo (7), W(8)) were prepared and characterized. These compounds are fluxional and display broad unresolved proton NMR signals at room temperature. Compounds 1-6 were characterized by NMR spectroscopy at −60 °C, which revealed isomers in solution. The major isomers of 1-4 adopt an asymmetric endo-conformation, while those of 5 and 6 were both found to possess a symmetric endo-conformation. The single crystal X-ray structures of 1-6 are consistent with the structures of the major isomer in solution at low temperature. In contrast to mononuclear terminal cyanide compounds 5 and 6, cyanide-bridged compounds 7 and 8 were found to adopt the asymmetric endo-conformation in the solid state.  相似文献   

8.
The diiron complexes [Fe(Cp)(CO){μ-η22-C[N(Me)(R)]NC(C6H3R′)CCH(Tol)}Fe(Cp)(CO)] (R = Xyl, R′ = H, 3a; R = Xyl, R′ = Br, 3b; R = Xyl, R′ = OMe, 3c; R = Xyl, R′ = CO2Me, 3d; R = Xyl, R′ = CF3, 3e; R = Me, R′ = H, 3f; R = Me, R′ = CF3, 3g) are obtained in good yields from the reaction of [Fe2{μ-CN(Me)(R)}(μ-CO)(CO)(p-NCC6H4R′)(Cp)2]+ (R = Xyl, R′ = H, 2a; R = Xyl, R′ = Br, 2b; R = Xyl, R′ = OMe, 2c; R = Xyl, R′ = CO2Me, 2d; R = Xyl, R′ = CF3, 2e; R = Me, R′ = H, 2f; R = Me, R′ = CF3, 2g) with TolCCLi. The formation of 3 involves addition of the acetylide at the coordinated nitrile and C-N coupling with the bridging aminocarbyne together with orthometallation of the p-substituted aromatic ring and breaking of the Fe-Fe bond. Complexes 3a-e which contain the N(Me)(Xyl) group exist in solution as mixtures of the E-trans and Z-trans isomers, whereas the compounds 3f,g, which posses an exocyclic NMe2 group, exist only in the Z-cis form. The crystal structures of Z-trans-3b, E-trans-3c, Z-trans-3e and Z-cis-3g have been determined by X-ray diffraction experiments.  相似文献   

9.
A terminally coordinated CO ligand in the complexes [Fe2{μ-CN(Me)R}(μ-CO)(CO)2(Cp)2][SO3CF3] (R = Me, 1a; R = Xyl, 1b; Xyl = 2,6-Me2C6H3), is readily displaced by primary and secondary amines (L), in the presence of Me3NO, affording the complexes [Fe2{μ-CN(Me)R}(μ-CO)(CO)(L)(Cp)2][SO3CF3] (R = Me, L = NH2Et, 4a; R = Xyl, L = NH2Et, 4b; R = Me, L = NH2Pri, 5a; R = Xyl, L = NH2Pri, 5b; R = Xyl, L = NH2C6H11, 6; R = Xyl, L = NH2Ph, 7; R = Xyl, L = NH3, 8; R = Me, L = NHMe2, 9a; R = Xyl, L = NHMe2, 9b; R = Xyl, = NH(CH2)5, 10). In the absence of Me3NO, NH2Et gives addition at the CO ligand of 1b, yielding [Fe2{μ-CN(Me)(Xyl)}(μ-CO)(CO){C(O)NHEt}(Cp)2] (11). Carbonyl replacement is also observed in the reaction of 1a-b with pyridine and benzophenone imine, affording [Fe2{μ-CN(Me)R}(μ-CO)(CO)(L)(Cp)2][SO3CF3] (R = Me, L = Py, 12a; R = Xyl, L = Py, 12b; R = Me, L = HNCPh2, 13a; R = Xyl, L = HNCPh2, 13b). The imino complex 13b reacts with p-tolylacetylide leading to the formation of the μ-vinylidene-diaminocarbene compound [Fe2{μ-η12- CC(Tol)C(Ph)2N(H)CN(Me)(Xyl){(μ-CO)(CO)(Cp2)] (15) which has been studied by X-ray diffraction.  相似文献   

10.
Mononuclear complexes of the type, M(CO)4[Se2P(OR)2] (M = Mn, R = iPr, 1a; Et, 1b; M = Re, R = iPr, 3a; Et, 3b) can be prepared from either [-Se(Se)P(OiPr)2]2 (A) or [Se{-Se(Se)P(OEt)2}2] (B) with M(CO)5Br. O,O′-dialkyl diselenophosphate ([(RO)2PSe2]-, abbreviated as dsep) ligands generated from A and B act as a chelating ligand in these complexes. Upon refluxing in acetonitrile, these mononuclear complexes yield dinuclear complexes with a general formula of [M2(CO)6{Se2P(OR)2}2] (M = Mn, R = iPr, 2a; Et, 2b; M = Re, R = iPr, 4a; Et, 4b). Dsep ligands display a triconnective, bimetallic bonding mode in the dinuclear compounds and this kind of connective pattern has never been identified in any phosphor-1,1-diselenoato metal complexes. Compounds 2b, 3b, and 4 are structurally characterized. Compounds 2b and 3b display weak, secondary Se?Se interactions in their lattices.  相似文献   

11.
The heteroditopic, P-N-chelating ligand diphenylphosphino(phenyl pyridin-2-yl methylene)amine (1) has been synthesised via a simple ‘one-pot’ procedure and its donor characteristics assessed. The neutral [MX(Y)(12-P-N)] (3, M = Rh, X = Cl, Y = CO; 4, M = Pd, X = Y = Cl; 5, M = Pd, X = Cl, Y = Me; 6, M = Pt, X = Y = Cl; 7, M = Pt, X = Cl, Y = Me; 8, M = Pt, X = Y = Me) and cationic [Pd(Me)(MeCN)(12-P-N)][Z] (9, Z = B{3,5-(CF3)2-C6H3}4; 10, Z = PF6) complexes of 1 have been prepared and characterised. The solid-state structures of complexes 3, 4, 6 and 7 have been established by X-ray crystallography. Reactions of [PdCl(Me)(12-P-N)] towards CO and tBuNC have been investigated, affording the corresponding η1-acyl (12) and -iminoacyl (14) complexes, respectively. Similar insertion chemistry is observed for the cationic derivative 9. Treatment of the acyl complex 12 with ethene at elevated pressure establishes an equilibrium between the starting material and the product resulting from insertion, 13. Under catalytic conditions, combination of palladium(II) with 1 in MeOH affords a selective initiator for the formation of 4-oxo-hexanoic acid methyl ester (15) from CO/ethene (38 bar, 90 °C).  相似文献   

12.
Coordinatively unsaturated rhodium and iridium complexes having a bulky thiolate, [Cp∗M(PMe3)(SDmp)](BArF4) (1a: M = Rh; 1b: M = Ir; Dmp = 2,6-(mesityl)2C6H3, ArF = 3,5-(CF3)2C6H3), catalyzed the hydrogenation of benzaldehyde, N-benzylideneaniline, and cyclohexanone, under 1 atm of H2 at low temperatures. In these catalytic reactions, the M-H/S-H complexes [Cp∗M(PMe3)(H)(HSDmp)](BArF4) (2a: M = Rh; 2b: M = Ir) generated via H2 heterolysis by 1a or 1b were suggested to transfer both M-H hydride and S-H proton to substrates. The catalytic reactions were terminated by the dissociation of H-SDmp from the metal centers of 2a and 2b that occurs at ambient temperature under H2 atmosphere.  相似文献   

13.
The bridging aminocarbyne complexes [Fe2{μ-CN(Me)(R)}(μ-CO)(CO)2(Cp)2][SO3CF3] (R = Me, 1a; Xyl, 1b; 4-C6H4OMe, 1c; Xyl = 2,6-Me2C6 H3) react with acrylonitrile or methyl acrylate, in the presence of Me3NO and NaH, to give the corresponding μ-allylidene complexes [Fe2{μ-η13- Cα(N(Me)(R))Cβ(H)Cγ(H)(R′)}(μ-CO)(CO)(Cp)2] (R = Me, R′ = CN, 3a; R = Xyl, R′ = CN, 3b; R = 4-C6H4OMe, R′ = CN, 3c; R = Me, R′ = CO2Me, 3d; R = 4-C6H4OMe, R′ = CO2Me, 3e). Likewise, 1a reacts with styrene or diethyl maleate, under the same reaction conditions, affording the complexes [Fe2{μ-η13-Cα(NMe2)Cβ(R′)Cγ(H)(R″)}(μ-CO)(CO)(Cp)2] (R′ = H, R″ = C6H5, 3f; R′ = R″ = CO2Et, 3g). The corresponding reactions of [Ru2{μ-CN(Me)(CH2Ph)}(μ-CO)(CO)2(Cp)2][SO3CF3] (1d) with acrylonitrile or methyl acrylate afford the complexes [Ru2{μ-η13-Cα(N(Me)(CH2Ph))Cβ(H)Cγ(H)(R′)}(μ-CO)(CO)(Cp)2] (R′ = CN, 3h; CO2Me, 3i), respectively.The coupling reaction of olefin with the carbyne carbon is regio- and stereospecific, leading to the formation of only one isomer. C-C bond formation occurs selectively between the less substituted alkene carbon and the aminocarbyne, and the Cβ-H, Cγ-H hydrogen atoms are mutually trans.The reactions with acrylonitrile, leading to 3a-c and 3h involve, as intermediate species, the nitrile complexes [M2{μ-CN(Me)(R)}(μ-CO)(CO)(NC-CHCH2)(Cp)2][SO3CF3] (M = Fe, R = Me, 4a; M = Fe, R = Xyl, 4b; M = Fe, R = 4-C6H4OMe, 4c; M = Ru, R = CH2C6H5, 4d).Compounds 3a, 3d and 3f undergo methylation (by CH3SO3CF3) and protonation (by HSO3CF3) at the nitrogen atom, leading to the formation of the cationic complexes [Fe2{μ-η13-Cα(N(Me)3)Cβ(H)Cγ(H)(R)}(μ-CO)(CO)(Cp)2][SO3CF3] (R = CN, 5a; R = CO2Me, 5b; R = C6H5, 5c) and [Fe2{μ-η13-Cα(N(H)(Me)2)Cβ(H)Cγ(H)(R)}(μ-CO)(CO)(Cp)2][SO3CF3] (R = CN, 6a; R = CO2Me, 6b; R = C6H5, 6c), respectively.Complex 3a, adds the fragment [Fe(CO)2(THF)(Cp)]+, through the nitrile functionality of the bridging ligand, leading to the formation of the complex [Fe2{μ-η13-Cα(NMe2)Cβ(H)Cγ(H)(CNFe(CO)2Cp)}(μ-CO)(CO)(Cp)2][SO3CF3] (9).In an analogous reaction, 3a and [Fe2{μ-CN(Me)(R)}(μ-CO)(CO)2(Cp)2][SO3CF3], in the presence of Me3NO, are assembled to give the tetrameric species [Fe2{μ-η13-Cα(NMe2)Cβ(H)Cγ(H)(CN[Fe2{μ- CN(Me)(R)}(μ-CO)(CO)(Cp)2])}(μ-CO)(CO)(Cp)2][SO3CF3] (R = Me, 10a; R = Xyl, 10b; R = 4-C6H4OMe, 10c).The molecular structures of 3a and 3b have been determined by X-ray diffraction studies.  相似文献   

14.
Four new complexes, {[M(NAIP)(H2O)4]·2H2O}n (M = Co (1), M = Mn (2)), {[Zn(NAIP)]·0.5H2O}n (3) and {Cd(NAIP)(H2O)2]·1.5H2O}n (4) [H2NAIP = 5-(nicotinamido)-isophthalic acid] have been prepared and structurally characterized. The ligand NAIP2− exhibits different coordination modes and leads to the formation of various architectures. Complexes 1 and 2 show a one-dimensional (1D) zigzag chain, where hydrogen-bonding interactions further link these chains to a three dimensional (3D) supramolecular structure. For complex 3, a 3D coordination network with a four-coordinated Zn(II) and NAIP2− as a SBU was observed. Complex 4 presents a three-connected 2-fold interpenetrated 3D network with a (10, 3)-b net topology. Their luminescent and magnetic properties have been investigated in the solid state.  相似文献   

15.
The reaction of Ni(OAc)2, NiX2 (X = Cl, Br) or CoCl2 with the proligand 2-amino-2-methyl-1,3-propanediol (ampdH2) affords a new family of tetranuclear complexes. The syntheses of [Ni4(OAc)4(ampdH)4] (1) and [M4X4(ampdH)4] (M = Ni, X = Cl, 2; M = Ni, X = Br, 3; M = Co, X = Cl, 4) are reported, together with the single crystal X-ray structures of 1, 2 and 4 and the magnetochemical characterization of 1, 3 and 4. Each member of this family of complexes displays a low symmetry structure that incorporates a {M4O4} core unit based on a distorted cubane. Magnetic measurements reveal ferromagnetic exchange interactions for 1, 3 and 4. These give rise to S = 4 ground state spins for the tetranuclear Ni complexes and an anisotropic effective S′ = 2 ground state for the Co complex.  相似文献   

16.
Compounds M(CO)23-C3H5)(L-L)(NCBH3) (L-L = dppe, M = Mo(1), W(2); L-L = bipy, M = Mo(3), W(4); L-L = en, M = Mo(5), W(6)) were prepared and characterized. The single crystal X-ray analyses of 2-6 revealed that the cyanotrihydroborate anion bonds to the metal through a nitrogen atom, the open face of the allyl group being pointed toward the two carbonyls (endo-isomer). In compounds 2, 5, and 6, the two donor atoms of the bidentate ligand occupy equatorial and axial positions, respectively. In the solid state structures of compounds 3 and 4 both nitrogen atoms of the bipy ligand occupy equatorial positions. The NMR spectroscopy reveals a fluxional behavior of compounds 1, 2, 5, and 6 in solution. Although the fluxional behavior of compounds 5 and 6 ceased at about −40 °C, that of compound 1 could not be stopped even at −90 °C. Their low temperature conformations are consistent with their solid state structures. Both the endo- and exo-isomers coexist in solution for compounds 3 and 4.  相似文献   

17.
A series of novel phenoxy-phosphinimine ligands (L): L = 2-(Ph2PNR), 4, 6-(CMe3)2-C6H2OH [2, R = SiMe3; 3, R = Ph] have been prepared in the yield of 65-71%. And bis(phenoxy-phosphinimide) group 4 complexes of the type L2MCl2 [4, M = Ti, R = SiMe3; 5, M = Zr, R = SiMe3; 6, M = Ti, R = Ph; 7, M = Zr, R = Ph] have been synthesized by the reaction of the ligands with TiCl4 and ZrCl4. The structure of complex 7 has been determined by X-ray crystallography. The complexes 4-7 showed inactive to ethylene polymerization in the presence of modified methylaluminoxane (MMAO) and i-Bu3Al/Ph3CB(C6 F5)4. These results should be caused by overdoing the steric congestion around central metal.  相似文献   

18.
N-Heterocyclic carbene ligands (NHC) were metalated with Pd(OAc)2 or [Ni(CH3CN)6](BF4)2 by in situ deprotonation of imidazolium salts to give the N-olefin functionalized biscarbene complexes [MX2(NHC)2] 3-7 (3: M = Pd, X = Br, NHC = 1,3-di(3-butenyl)imidazolin-2-ylidene; 4: M = Pd, X = Br, NHC = 1,3-di(4-pentenyl)imidazolin-2-ylidene; 5: M = Pd, X = I, NHC = 1,3-diallylimidazolin-2-ylidene; 6: M = Ni, X = I, NHC = 1,3-diallylimidazolin-2-ylidene; 7: M = Ni, X = I, NHC = 1-methyl-3-allylimidazolin-2-ylidene). Molecular structure determinations for 4-7 revealed that square-planar complexes with cis (5) or trans (4, 6, 7) coordination geometry at the metal center had been obtained. Reaction of nickelocene with imidazolium bromides afforded the η5-cyclopentadienyl (η5-Cp) monocarbene nickel complexes [NiBr(η5-Cp)(NHC)] 8 and 9 (8: NHC = 1-methyl-3-allylimidazolin-2-ylidene; 9: NHC = 1,3-diallylimidazolin-2-ylidene). The bromine abstraction in complexes 8 and 9 with silver tetrafluoroborate gave complexes [NiBr(η5-Cp)(η3-NHC)] 10 and 11. The X-ray structure analysis of 10 and 11 showed a trigonal-pyramidal coordination geometry at the nickel(II) center and coordination of one N-allyl substituent.  相似文献   

19.
Treatment of [Cp′MH(CO)3] (M = Mo, W; Cp′ = η5-C5H5 (Cp), η5-C5Me5 (Cp*)) with 1/8 equiv of S8 in THF, followed by the reaction with dppe under UV irradiation, gave new mono(hydrosulfido) complexes [Cp′M(SH)(CO)(dppe)] (Cp′ = Cp: M = Mo (5), W (6); Cp′ = Cp*: M = Mo (7), W (8); dppe = Ph2PCH2CH2PPh2). When 5 and 6 dissolved in THF were allowed to react with [RhCl(PPh3)3] in the presence of base, heterodinuclear complexes with bridging S and dppe ligands [CpM(CO)(μ-S)(μ-dppe)Rh(PPh3)] (M = Mo (9), W(10)) were obtained. Semi-bridging feature of the CO ligands were also demonstrated. Upon standing in CH2Cl2 solutions, 9 and 10 were converted further to the dimerization products [(CpM)2{Rh(dppe)}22-CO)23-S)2] (M = Mo (13), W). Detailed structures of mononuclear 7 and 8, dinuclear 9 and tetranuclear 13 have been determined by the X-ray diffraction.  相似文献   

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