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1.
The complexes (Hal)Nb(CO)3(PR3)3 (PR3 = PEt3, Hal = I; PR3 = PMe2Ph, Hal = Cl, Br, I) and (Hal)Nb(CO)4/2(dppe)1/2 (Hal = Br, I) have been prepared by oxidative halogenation of carbonylniobate with pyridinium halides (Hal = Cl, Br) or iodine (Hal = I). In the tricarbonyls, one CO and one PR3 are labile and can be displaced by a four-electron donating alkyne to give all-trans-[(Hal)Nb(CO)2(RCCR′)(PR3)2] (PR3 = PMe2Ph; Hal = Cl, Br, I: R, R′ = H, Et, Ph; R = H, R′ = Ph. PR3 = PEt3, Hal = I: R, R′ = Pr; R = H, R′ = Bu, Ph; R = Me, R′ = Et). In the case of acetylene, INb(CO)(HCCH)2(PEt3)2 is also formed. PR3 can be displaced by P(OMe) 3. In the tetracarbonyls, two CO ligands are replaced by two isonitriles to form INb(CO)2(CNR)2dppe (R = tBu, Cy), or by one alkyne to form (Hal)Nb(CO)2(PhCCPh)dppe (Hal = Br, I). In these complexes, the remaining CO ligands occupy cis positions. The structure of BrNb(CO)2(dppe)2·THF, INb(CO)2(dppe)2·hexane and INb(CO)2(PEt3)2(MeCCEt) have been determined by a single crystal X-ray diffraction study. The alkyne complexes are best regarded as octahedral with the centre of the alkyne ligand occupying the positions trans to the halide and the CC axis aligned with the OC---Nb---CO axis. The complexes (Hal)Nb(CO)2(dppe)2 adopt a trigonal prismatic structure with the halide capping the tetragonal face spanned by the four phosphorus functions. The crystal structure of a by-product, Br2Nb(CO)(H2CPhPCH2CH2PPh2)2·1/2THF has also been determined. The geometry is pentagonal bipyramidal, with one of the bromine atoms and the CO on the axis. Some 93 Nb NMR data for the NbI complexes are presented, and preliminary observations on the reactions between the π-alkyne complexes and H2 or H are reported.  相似文献   

2.
The reactions of M(CO)4(R′-DAB) (M = Mo) or W; R′-DAB = R′-N=CHCH=NR′ (R′ = i-propyl, t-butyl, or cyclohexyl) with SnCl4 in dichloromethane solution result in the formation, in high yield, of the orange, diamagnetic, seven-coordinate oxidative-addition products M(CO)3(R′-DAB)(SnCl3)Cl. The reactions of Mo(CO)3(R′-DAB)(SnCl3)Cl (R′ = i-Pr or Cy) with an excess of alkyl isocyanide RNC (R = CHMe2, CMe3, or C6H11) in the presence of KPF6 lead to the formation of [Mo(CNR)4(R′-DAB)Cl]PF6 or [Mo(CNR)5(R′-DAB)](PF6)2 depending upon the reaction stoichiometry and reaction conditions. The monocationic chloro species are converted to [Mo(CNR)5(R′-DAB)](PF6)2 upon reflux with the stoichiometric amount of RNC. Under similar reactions conditions M(CO)3(t-Bu-DAB)(SnCl3)Cl (M = Mo or W) derivatives react with alkyl isocyanides with the reductive-elimination of the elements of SnCl4 and the formation of octahedral M(CO)3(CNR)(t-Bu-DAB). The dark red compounds [Mo(CNCMe3)5(R′-DAB)](PF6)2 (R′ = i-Pr or Cy) react readily with cyanide ions at ambient temperatures in methanol to yield [Mo(CNCMe3)4(R′-DAB)(CN)]PF6. Attempts to thermally dealkylate the parent complexes [Mo(CNCMe3)5(R′-DAB)](PF6)2 (R′ = i-Pr or Cy) to these same cyano species were unsuccessful.  相似文献   

3.
The methylene-bridged, mixed-chalogen compounds Fe2(CO)6(μ-SeCH2Te) (1) and Fe2(CO)6(μ-SCH2Te) (3) have been synthesised from the room temperature reaction of diazomethane with Fe2(CO)6(μ-SeTe) and Fe2(CO)6(μ-STe), respectively. Compounds 1 and 3 have been characterised by IR, 1H, 13C, 77Se and 125Te NMR spectroscopy. The structure of 1 has been elucidated by X-ray crystallography. The crystalsare monoclinic,space group P21/n, A = 6.695(2), B = 13.993(5), C = 14.007(4)Å, β = 103.03(2)°, V = 1278(7) Å3, Z = 4, Dc = 2.599 g cm−3 and R = 0.030 (Rw = 0.047).  相似文献   

4.
The diol R2C(SiMe2OH)2 (R = Me3Si) has been shown to react with: SO2Cl2 to give R2 Me2; SOCl2 to give R2C(SiMe2Cl)2; Me3SiI or Me3SiCl to give R2C(SiMe2OSiMe3)2; R′COCl; (R′ = Me or CF3) to give R2C(SiMe2O2CR′)-(SiMe2Cl); (R′CO)2O (R′ = Me or CF3 to give R2C(SiMe2O2CR′)2; with MeOH containing acid to give R2C(SiMe2OMe)2; with neutral MeOH to give R2C-(SiMe2OMe)2 and probably R2 Me2; MeLi to give R2C(SiMe2OLi)2 (and the latter to react with PhMeSiF2 to give R2 Me2). The diacetate R2C(SiMe2O2CMe)2 reacts with CsF in MeCN to give R2C(SiMe2F)2; it does not react with NaN3 or KSCN in MeCN, but the bis(trifluoroacetate) reacts with these salts with KOCN to give R2C(SiMe2X)2 (X = N3, NCS, NCO).  相似文献   

5.
Reactions of FcCCH (a), HCCCCFc (b) and FcCCCCFc (c) with Ru3(CO)10(NCMe)2 (all) and Ru3(μ-dppm)(CO)10 (b and c only) are described. Among the products, the complexes Ru33-RC2R′)(μ-CO)(CO)9 (R=H, R′=Fc 1, CCFc 2; R=R′=Fc 5), Ru3(μ-H)(μ3-C2CCFc)(μ-dppm)(CO)7 3, Ru33-FcC2CCFc)(μ-dppm)(μ-CO)(CO)7 6 and Ru33-C4Fc2(CCFc)2}(μ-dppm)(μ-CO)(CO)5 7 were characterised, including single-crystal structure determinations for 1, 3, 5 and 7; that of 7 did not differ significantly from an earlier study of a mixed CH2Cl2–C6H6 solvate.  相似文献   

6.
A high yield synthesis of the carbonyl dithiocarbamato derivative Fe(CO)22-S2CNMe2)2 and Fe(η2-S2CNMe2)2 by photolysis with visible light of solutions containing Fe2(CO)9 or Fe3(CO)12 and [(η5-C5H5)(CO)3W(η1-SCSNMe2)] is reported.  相似文献   

7.
Phosphines react with butterfly tetranuelear nitrido-iron clusters, [Fe4N(CO)12] and [Fe4N(CO)11(NO)], to give mono- and di-substituted complexes. X-Ray analyses of the title compounds showed that the phosphine ligands are bound to the wing-tip atoms.  相似文献   

8.
The dimethylphosphino substituted cyclopentadienyl precursor compounds [M(C5Me4CH2PMe2)], where M=Li+ (1), Na+ (2), or K+ (3), and [Li(C5H4CR′2PMe2)], where R′2=Me2 (4), or (CH2)5 (5), [HC5Me4CH2PMe2H]X, where X=Cl (6) or PF6 (7) and [HC5Me4CH2PMe2] (8), are described. They have been used to prepare new metallocene compounds, of which representative examples are [Fe(η-C5R4CR′2PMe2)2], where R=Me, R′=H (9); R=H and R′2=Me2 (10), or (CH2)5 (11), [Fe(η-C5H4CMe2PMe3)2]I2 (12), [Fe{η-C5Me4CH2P(O)Me2}2] (13), [Zr(η-C5R4CR′2PMe2)2Cl2], where R=H, R′=Me (14), or R=Me, R′=H (15), [Hf(η-C5H4CMe2PMe2)2]Cl2] (16), [Zr(η-C5H4CMe2PMe2)2Me2] (17), {[Zr(η-C5Me4CH2PMe2)2]Cl}{(C6F5)3BClB(C6F5)3} (18), [Zr{(η-C5Me4CH2PMe2)2Cl2}PtI2] (19), [Mn(η-C5Me4CH2PMe2)2] (20), [Mn{(η-C5Me4CH2PMe2B(C6F5)3}2] (21), [Pb(η-C5H4CMe2PMe2)2] (23), [Sn(η-C5H4CMe2PMe2)2] (24), [Pb{η-C5H4CMe2PMe2B(C6F5)3}2] (25), [Pb(η-C5H4CMe2PMe2)2PtI2] (26), [Rh(η-C5Me4CH2PMe2)(C2H4)] 29, [M(η,κP-C5Me4CH2PMe2)I2], where M=Rh (30), or Ir, (31).  相似文献   

9.
The compounds (π-C5H5)(CO)2LM-X (L = CO, PR3; M = Mo, W; X = BF4, PF6, AsF6, SbF6) react with H2S, p-MeC6H4SH, Ph2S and Ph2SO(L′) to give ionic complexes [(π-C5H5)(CO)2LML′]+ X. Also sulfur-bridged complexes, [(π-C5H5)(CO)3W---SH---W(CO)3(π-C5H5)]+ AsF6 and [(π-C5H5)(CO)3M-μ-S2C=NCH2Ph-M(CO)3(π-C5H5)], have been obtained. Reactions with SO2 and CS2 have been examined.  相似文献   

10.
Three families of heterobimetallic compounds were obtained by reaction of [Mo(CO)3(CH3CN)2(Cl)(SnRCl2)] (R = Ph, Me) with P(4-XC6H4)3 (X = Cl, F, H, Me, MeO). The type of compound obtained dependent on the solvent and concentration of the starting compound. So, [Mo(CO)2(CH3COCH3)2(PPh3)(Cl)(SnRCl2)]·nCH3COCH3 (R = Ph, n = 0.5; R = Me, n = 1) (type I) and [Mo(CO)3{P(4-XC6H4)3}(μ-Cl)(SnRCl2)]2 (R = Ph, X = Cl, F, H, Me, MeO; R = Me, X = Cl, F) (type II) were isolated from acetone solution in ca 0.05 M and 0.1 M concentrations, respectively. However, [Mo(CO)3(CH3CN) {P(4-XC6H4)3}(Cl)(SnRCl2)] (R = Ph, X = H; R = Me, X = Cl, F, H) (type III) were obtained from dichloromethane solution independently of the concentration used. All new complexes showed a seven-coordinate environment at molybdenum, containing Mo---Cl and Mo---Sn bonds. Mössbauer spectra indicated a four-coordination at tin for type III complexes.  相似文献   

11.
The reaction of trans-X(CO)4WCNR2 (X = Br, R = c hex (cyclohexyl); X = Cl, R = c hex, ipr (isopropyl) with M+X (M+ = NEt4+, X = Br; M+ = PPN+, X = Cl) leads under substitution of one CO ligand to new anionic dihalo(tricarbonyl)carbyne-tungsten complexes of the type M+ mer-[(X)2(CO)3WCNR2] (M+ = NEt4+, X = Br, R = c hex; M+ = PPN+, X = Cl, R = c hex, i pr), whose composition and structure were determined by elemental analysis as well as by IR, 1H and 13C NMR spectroscopy. In the anionic carbyne complexes the entered halogen ligand, coordinated in a cis position relative to the carbyne ligand on the metal, can be easily substituted by neutral nucleophiles, as the reaction of PPN+ mer-[(Cl)2(CO)3WCNchex2] with PPh3 demonstrates yielding the neutral carbyne complex mer-[Cl(CO)3(PPh3)WCNchex2].  相似文献   

12.
Reductive dehalogenation of the (chloro)(phenylethynyl)phosphine (2,4,6-tBu3C6H2O)(PhCC)PCl, I, by Co2(CO)8, II, yields the neutral phosphenium ion complex [(R)(R′)]P=Co(CO)3, III, (R = 2,4,6-tBu3C6H2O; R′ = (η2-C≡CPh)Co2(CO)6), which contains a trigonally planar coordinated phosphorus atom. When NaCo(CO)4, V, is used instead of II a dinuclear complex, Co2(CO)62-P(R)(R′)]2, VI, (R = 2,4,6-tBu3C6H2O; R′ = C≡CPh) is formed in which the phosphido ligands P(R)(R′), bridge in a μ2 fashion two Co(CO)3 units. The mechanism of formation of VI, involving a formal dimerization of two [(2,4,6-tBu3C6H2O)(PhC≡C)]P=Co(CO)3 fragments, is discussed. However, (tBu)(PhC≡C)PCl, VII, reacts with II, to yield the cluster compound VIII, containing the two μ2-bridging units (tBu)[(η2-C≡CPh)Co2(CO)5]P and (tBu)(PhC≡C)P.

Compounds II and VI–VIII were identified from their analytical and spectroscopic (IR, 1H-, 13C- and 31P-NMR) data. The molecular structure of the cluster compound VIII was determined by an X-ray diffraction study.  相似文献   


13.
Photolysis of the tetraruthenaborane butterfly cluster HRu4(CO)12BH2 with 1-phenyl-1-propyne yields the cluster product HRu4(CO)12B(H)C(Ph)CMeH. Interestingly, 1-phenyl-2,3-dimethylazulene has also been isolated from the reaction mixture. The formation of this substituted azulene is an example of a novel cyclodimerisation of the alkyne. The crystal structure of 1-phenyl-2,3-dimethylazulene has been determined.  相似文献   

14.
Toluene solutions of M2(NMe2)6 (M = Mo, W) react with mesitylene selenol (Ar′SeH) to give M2(SeAr′) 6 complexes. MO2(OR)6 (R = tBu, CH2tBu) react with excess> 6 fold) Ar′SeH to give Mo2 (SeAr′)6, whilst W2(OR)6(py)2 (R = iPr, CH2tBu) react with excess (> 6 fold) Ar′SeH to give W2(OR)2(SeAr′)4. Reaction of MO2(OPri)6 with Ar′SeH produces Mo2(OPri)2 (SeAr′)4 which crystallizes in two different space groups. These areneselenato complexes are air-stable and insoluble in common organic solvents. X-ray crystallographic studies revealed that the Mo2(SeAr′)6 and W2(SeAr′)6 compounds are isostructural in the solid state and adopt ethane-like staggered configurations with the following important structural parameters, M---M (W---W/Mo---Mo) 2.3000(11)/2.2175(13) Å, M---Se 2.430 (av.)/2.440 (av.) Å, M---M---SE 97.0° (av.)°. In the solid state W2(OiPr)2(SeAr′)4 adopts the anti-configuration with crystallographically imposed Ci symmetry and W---W 2.3077(7) Å, W---Se 2.435 (av.) Å, W---O 1.858(6) Å; W---W---SE 100.27(3)°, 93.8(3)° and W---W---O 108.41(17)°. Mo2(OPri)2(SeAr′) 4 crystallizes in both P and A2/a space groups in which the molecules are isostructural with each other and the tungsten analogue. Important bond lengths and angles are Mo---Mo 2.180(24) Å, Mo---Se 2.432(av.) Å, Mo---O 1.872(9) Å, Mo---Mo---Se 99.39(9)°, 94.71(8)°, Mo---Mo---O 107.55(28)°.  相似文献   

15.
16.
The reactions of RNHSi(Me)2Cl (1, R=t-Bu; 2, R=2,6-(Me2CH)2C6H3) with the carborane ligands, nido-1-Na(C4H8O)-2,3-(SiMe3)2-2,3-C2B4H5 (3) and Li[closo-1-R′-1,2-C2B10H10] (4), produced two kinds of neutral ligand precursors, nido-5-[Si(Me)2N(H)R]-2,3-(SiMe3)2-2,3-C2B4H5, (5, R=t-Bu) and closo-1-R′-2-[Si(Me)2N(H)R]-1,2-C2B10H10 (6, R=t-Bu, R′=Ph; 7, R=2,6-(Me2CH)2C6H3, R′=H), in 85, 92, and 95% yields, respectively. Treatment of closo-2-[Si(Me)2NH(2,6-(Me2CH)2C6H3)]-1,2-C2B10H11 (7) with three equivalents of freshly cut sodium metal in the presence of naphthalene produced the corresponding cage-opened sodium salt of the “carbons apart” carborane trianion, [nido-3-{Si(Me)2N(2,6-(Me2CH)2C6H3)}-1,3-C2B10H11]3− (8) in almost quantitative yield. The reaction of the trianion, 8, with anhydrous MCl4 (M=Ti and Zr) in 1:1 molar ratio in dry tetrahydrofuran (THF) at −78 °C, resulted in the formation of the corresponding half-sandwich neutral d0-metallacarborane, closo-1-M[(Cl)(THF)n]-2-[1′-η1σ-N(2,6-(Me2CH)2C6H3)(Me)2Si]-2,4-η6-C2B10H11 (M=Ti (9), n=0; M=Zr (10), n=1) in 47 and 36% yields, respectively. All compounds were characterized by elemental analysis, 1H-, 11B-, and 13C-NMR spectra and IR spectra. The carborane ligand, 7, was also characterized by single crystal X-ray diffraction. Compound 7 crystallizes in the monoclinic space group P21/c with a=8.2357(19) Å, b=28.686(7) Å, c=9.921(2) Å; β=93.482(4)°; V=2339.5(9) Å3, and Z=4. The final refinements of 7 converged at R=0.0736; wR=0.1494; GOF=1.372 for observed reflections.  相似文献   

17.
Reaction of optically active ketone complexes (+)-(R)-[(η5-C5H5)Re(NO)-(PPh3)(η1-O=C(R)(CH3)]+ BF4 (R = CH2CH3, CH(CH3)2m C(CH3)3, C6H5) with K(s-C4H9)3BH gives alkoxide complexes (+)-(RS)-(η5-C5H5)Re(NO)(PPh3)-(OCH(R)CH3) (73–90%) in 80–98% de. The alkoxide ligand is then converted to Mosher esters (93–99%) of 79–98% de.  相似文献   

18.
Protonation of the lithium triphospha-cyclopentenyl salt Li (P3C2But2RR′) (R=(Me3Si)2CH-, R′=Bun) with HCl affords the new 2,3-dihydro-1H-[1,2,4] triphosphole P3C2But2(H) (Bun)CH(SiMe3)2 which has been structurally characterised as its [W(CO)5] complex.  相似文献   

19.
The aryldiazenido ligands provide the fourth member of the isoelectronic series CO, NO+, RNC, RN2+ of ligands for transition metal complexes. The first aryldiazenido metal complex was reported in 1964 when p-CH3OC6H4N2Mo(CO)2C5H5 was prepared by the reaction of NaMo(CO)3C5H5 with p-CH3OC6H4N2+BF4. This review surveys the development of organometallic aryldiazenido chemistry since that time. Such organometallic aryldiazenido derivatives, including RN2M(CO)2C5H5, RN2M(CO)2(Pz3BH) (M = Cr, Mo, W), [(η6-Me6C6)Cr(CO)2N2Ar]+, [(MeC15H4)M′(CO)2N2Ar]+ M′ = Mn, Re), [trans-PhN2Fe(CO)2(PPh3)2]+, and PhN2M′(CO)2(PPh3)2(PPh3)2 can be obtained by reactions of arenediazonium salts with suitably chosen transition metal nucleophiles. Analogous methods cannot be used to prepare alkyldiazenido transition metal complexes because of the instability of alkyldiazonium salts. However, the alkyldiazenido derivatives RCH2N2M(CO)2C5H5 (R = H or Me3Si) can be obtained from HM(CO)3C5H5 and the corresponding diazoalkanes. Important aspects of the chemical reactivity of RN2M(CO)2Q derivatives (Q = C5H5, Pz3BH) include CO substitution reactions, coordination of the second nitrogen in the RN2 ligand to give heterobimetallic complexes such as C5H5Mo(CO)2(μ-NNC6H4Me)(CO)2C5H5, oxidative addition rections with X2 X = Cl, Br, I), SnX4, RSSR, and CINO, and reactions with further RN2+ to give bis(aryldiazenido) derivatives (RN2)2MQL+ (L = CO, X, etc.). Dearylation of an aryldiazenido ligand to a dinitrogen ligand can be effected by reaction of [(MeC5H4)M′(CO)2N2Ar]+ with certain nucleophiles to give (MeC5H4)M′(CO)2N2.  相似文献   

20.
Synthesis of H3Ru33-CSEt)(CO)9, is accomplished by base-promoted attack of ethanethiol on H3Ru33-CBr)(CO)9. Thermolysis of this product under CO yields HRu3(CH2SEt)(CO)9. Reactions of H3Ru33-CSEt)(CO)9 with alkynes C2R2 form HRu333-EtSCCRCR)(CO)9 (R = Me or Ph) and Ru3 (cis-CR=CHR)(CSEt)(CO)9 (R = Me). The chemistry of H3Ru33-CSEt)(CO)9 differs significantly from that of the analogous ether derivative H3Ru33-COMe)(CO)9.  相似文献   

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