首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
Co2(CO)8 and Hg[Co(CO)4]2 react sodium amalgam and/or mercury in ethereal solvents to give a variety of products. On treatment with aqueous M(o-phen)3Cl2(M  Fe, Ni), the anions [Co(CO)4?, [Co3(CO)10]?, {Hg[Co(CO)4]3}? and {Hg[Co(CO)4]2Cl}? could be isolated as their [M(o-phen)3]2+ salts. The effect of LiBr on the reacting systems was also investigated and the anion {Hg[Co(CO)4]2Br}? isolated.  相似文献   

2.
Co2(CO)8 catalyzes the ring‐opening copolymerization of propylene oxide with CO to afford the polyester in the presence of various amine cocatalysts. The 1H and 13C{1H} NMR spectra of the polyester, obtained by the Co2(CO)8–3‐hydroxypyridine catalyst, show the following structure ? [CH2? CH(CH3)? O? CO]n? . The Co2(CO)8–phenol catalyst gives the polyester, which contains the partial structural unit formed through the ring‐opening copolymerization of tetrahydrofuran with CO. The bidentate amines, such as bipyridine and N,N,N′,N′‐tetramethylethylenediamine, enhance the Co complex‐catalyzed copolymerization, which produces the polyester with a regulated structure. Acylcobalt complexes, (RCO)Co(CO)n (R = Me or CH2Ph), prepared in situ, do not catalyze the copolymerization even in the presence of pyridine. This suggests that the chain growth involves the intermolecular nucleophilic addition of the OH group of the intermediate complex to the acyl–cobalt bond, forming an ester bond rather than the insertion of propylene oxide into the acyl–cobalt bond. Co2(CO)8? Ru3(CO)12 mixtures also bring about the copolymerization of propylene oxide with CO. The molar ratio of Ru to Co affects the yield, molecular weight, and structure of the produced copolymer. The catalysis is ascribed to the Ru? Co mixed‐metal cluster formed in the reaction mixture. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4530–4537, 2002  相似文献   

3.
The sole and unexpected products from the reactions of a variety of lead (II) and lead (IV) compounds with [Co2(CO)6(L)2] complexes (L = tertiary arsine, phosphine, or phosphite) in refluxing benzene solution are the blue, air-stable percobaltoplumbanes [Pb{Co(CO)3(L)}4]. These have also been obtained from the reaction of Na[Co(CO)3(L)] (L  PBu3n) with lead (II) acetate which with Na[Fe(CO)2(NO)(L)] forms the isoelectronic [Pb{Fe(CO)2(NO)(L)}4] [L  P(OPh)3]. The IR spectra of the complexes in the v(CO) and v(NO) regions are consistent with tetrahedral PbCo4 or PbFe4 fragments, trigonal bipyramidal coordination about the cobalt or iron atoms and linear PbCoAs, PbCoP, or PbFeP systems. Unlike [Pb{Co(CO)4}4], our complexes do not dissociate to [Co(CO)3(L)]? or [Fe(CO)2(NO)(L)]? ions when dissolved in donor solvents.  相似文献   

4.
Formation of Organosilicon Compounds. 80. Si-Metalation of 1,3,5-Trisilacyclohexanes by Means of Trisition Metal Complexes Several Si-transition metal-substituted 1,3,5-trisilacyclohexanes are reported. l-Bromo-1,3,5-trisilacyclohexane reacts with the metal carbonyl anions W(CO)5cp?, Mo(CO)3cp-, Cr(CO)3cp?, Mn(CO)3?, Fe(CO)2cp?, or Co(CO)4minus;, resp., yielding monosubstituted derivatives as 6, e. g.(cp = π-cyclopentadienyl). 1,3-Dibromo-1,3,5-trisilacyclohexane forms disubstituted compounds aa 7, e. g., with 2 moles of the metal carbonyl anions Fe(CO)2cp?, Mn(CO)5? or Co(CO)4?. Starting from (H2c? SiHBr)3 compound 13 is accessible by reaction with KCo(CO)4. In the soluted compounds the metal carbonyl groups occupy the equatorial positions in the chair form of the six membered ring. The reaction of 13 with Co2(CO)8 yields 17 , whereas 6 preferrably forms 18 . Starting from (H2C? SiH2)3 the reaction with Co2(CO)2 preferrably yields 19. The reported compounds are crystalline, air – and moisture – sensitive. The reported formulae are assured by analysis, IR, and NMR investigations.  相似文献   

5.
Three transition‐metal–carbonyl complexes [V( L )(CO)3(Cp)] ( 1 ), [Co( L )(CO)(Cp)] ( 2 ), and [Co( L2 )(CO)3]+[CoCO)4]? ( 3 ), each containing stable N‐heterocyclic‐chlorosilylene ligands ( L ; L =PhC(NtBu)2SiCl) were synthesized from [V(CO)4(Cp)], [Co(CO)2(Cp)], and Co2(CO)8, respectively. Complexes 1 , 2 , 3 were characterized by NMR and IR spectroscopy, EI‐MS spectrometry, and elemental analysis. The molecular structures of compounds 1 , 2 , 3 were determined by single‐crystal X‐ray diffraction.  相似文献   

6.
Metal Complexes with Anionic Ligands of the Main Group IV Elements. IX. Reactions of Trichlorostannide and Trichlorogermide Ions with Complexes of Transition Metals in Low Oxidation States Carhonyl trichlorostannido- and carbonyl trichlorogermido-metalate complexes have been synthesized both by photochemical and thermical substitution reactions of [ECl3]? ions (E = Sn, Ge) with M(CO)6, (M = Cr, Mo, W), Fe(CO)5 Fe3(CO)12, Co2(CO)8, as well as with the metalcarbonyl derivatives (π-arene)M(CO)3, (M = Cr, Mo), (h5-C5,H5,)V(CO)4, Mn(CO)5,Cl, Co(NO)(CO)3, and Fe(NO)2,(CO)2. Mainly the bonding properties of the [ECl3]? ligands are discussed by means of i.r. spectroscopic investigations. The progress of the reactions and the necessary reaction conditions show that the nucleophilic properties oft both anions [ECl3]? are unexpectedly small. The slightly weaker hasicity of [SnCl3]? compared with [GeC13]? arreared, when both anions were reacted with Co2,(CO)8, forming the substitution product. [Co2,(CO)7,SnCl3]? and the products of a “base reaction” Cl3GcCo(CO)4, and [Co(CO)4]?.  相似文献   

7.
The betain‐like compound S2CC(PPh3)2 ( 1 ), which is obtained from CS2 and the double ylide C(PPh3)2, reacts with [Co2(CO)8] and [Mn2(CO)10] in THF to afford the salt‐like complexes [Co{S2CC(PPh3)2}3][Co(CO)4]3 ( 2 ) and [(CO)4Mn{S2CC(PPh3)2}][Mn(CO)5] ( 3 ), respectively, in good yields. At both d6 cations 1 acts as a chelating ligand. Disproportionation reactions from formal Co0 into CoIII and Co?I and from Mn0 into MnI and Mn?I occurred with the removal of four or one carbonyl groups, respectively. The crystal structures of 2· 5.5THF and 3· 2THF are reported, which show a shortening of the C–C bond in the ligand upon complex formation. The compounds are further characterized by 31P NMR and IR spectroscopy.  相似文献   

8.
以含羧酸配体的钴羰基簇合物Co2(CO)6HCCCOOH,Co3(CO)9CCH2COOH,Co4(CO)10HCCCOOH 为前驱体,γ-Al2O3为载体,通过浸渍法制备了一系列催化剂;同时以Co(NO32作为前驱体制备了参比催化剂. 对制备的催化剂进行了费托反应性能评价,并用透射电子显微镜、氨程序升温脱附和傅里叶变换红外光谱等手段对催化剂进行了表征. 结果发现,不同前驱体制备的催化剂对载体上Co的分布具有明显影响,进而影响催化剂活性. 反应结果表明,不同前驱体制备的催化剂上CO转化率及C5+选择性顺序为Co3(CO)9CCH2COOH > Co2(CO)6HCCCOOH > Co4(CO)10HCCCOOH > Co(NO32.  相似文献   

9.
The synthesis and reactivity of a CoI pincer complex [Co(?3P,CH,P‐P(CH)PNMeiPr)(CO)2]+ featuring an η2‐ Caryl?H agostic bond is described. This complex was obtained by protonation of the CoI complex [Co(PCPNMeiPr)(CO)2]. The CoIII hydride complex [Co(PCPNMeiPr)(CNtBu)2(H)]+ was obtained upon protonation of [Co(PCPNMeiPr)(CNtBu)2]. Three ways to cleave the agostic C?H bond are presented. First, owing to the acidity of the agostic proton, treatment with pyridine results in facile deprotonation (C?H bond cleavage) and reformation of [Co(PCPNMeiPr)(CO)2]. Second, C?H bond cleavage is achieved upon exposure of [Co(?3P,CH,P‐P(CH)PNMeiPr)(CO)2]+ to oxygen or TEMPO to yield the paramagnetic CoII PCP complex [Co(PCPNMeiPr)(CO)2]+. Finally, replacement of one CO ligand in [Co(?3P,CH,P‐P(CH)PNMeiPr)(CO)2]+ by CNtBu promotes the rapid oxidative addition of the agostic η2‐Caryl?H bond to give two isomeric hydride complexes of the type [Co(PCPNMeiPr)(CNtBu)(CO)(H)]+.  相似文献   

10.
The reaction of stibinidene and bismuthinidene ArM [where Ar=C6H3‐2,6‐(CH=NtBu)2; M=Sb ( 1 ), Bi ( 2 )] with transition metal (TM) carbonyls Co2(CO)8 and Mn2(CO)10 produced unprecedented ionic complexes [(ArM)2Co(CO)3]+[Co(CO)4]? and [(ArM)2Mn(CO)4]+[Mn(CO)5]? [where M=Sb ( 3 , 5 ), Bi ( 4 , 6 )]. The pnictinidenes 1 and 2 behaved as two‐electron donors in this set of compounds. Besides the M→TM bonds, the topological analysis also revealed a number of secondary interactions contributing to the stabilization of cationic parts of titled complexes.  相似文献   

11.
The reaction of equimolar amounts of [Co(CO)3(NO)] and [PPN]CN, PPN+ = (PPh3)2N+, in THF at room temperature resulted in ligand substitution of a carbonyl towards the cyanido ligand presumably affording the complex salt PPN[Co(CO)2(NO)(CN)] as a reactive intermediate species which could not be isolated. Applying the synthetic protocol using the nitrosyl carbonyl in excess, the title reaction afforded unexpectedly the novel complex salt PPN[Co2(μ-CN)(CO)4(NO)2] ( 1 ) in high yield. Because of many disorder phenomena in crystals of 1 the corresponding NBu4+ salt of 1 has been prepared and the molecular structure of the dinuclear metal core in NnBu4[Co2(μ-CN)(CO)4(NO)2] ( 2 ) was determined by X-ray crystal diffraction in a more satisfactory manner. In contrast to the former result, the reaction of [PPN]SCN with [Co(CO)3(NO)] yielded the mononuclear complex salt PPN[Co(CO)2(NO)(SCN-κN)] ( 3 ) in good yield whose molecular structure in the solid was even determined and its composition additionally confirmed by spectroscopic means.  相似文献   

12.
Coordination Chemistry of P‐rich Phosphanes and Silylphosphanes. XIX. [Co4P2(PtBu2)2(CO)8] and [{Co(CO)3}2P4tBu4] from Co2(CO)8 and tBu2P–P=P(Me)tBu2 Co2(CO)8 reacts with tBu2P–P=P(Me)tBu2 yielding the compounds [Co4P2(PtBu2)2(CO)8] ( 1 ) and [{η2tBu2P=P–P=PtBu2}{Co(CO)3}2] ( 2 a ) cis, ( 2 b ) trans. In 1 , four Co and two P atoms form a tetragonal bipyramid, in which two adjacent Co atoms are μ2‐bridged by tBu2P groups. Additionally, two CO groups are linked to each Co atom. In 2 a and 2 b , each of the Co(CO)3 units is η2‐coordinated to the terminal P2 units resulting in the cis‐ and trans‐configurations 2 a and 2 b . 1 crystallizes in the orthorhombic space group Pnnm (No. 58) with a = 879,41(5), b = 1199,11(8), c = 1773,65(11) pm. 2 a crystallizes in the monoclinic space group P21/n (No. 14) with a = 875,97(5), b = 1625,36(11), c = 2117,86(12) pm, β = 91,714(7)°. 2 b crystallizes in the triclinic space group P 1 (No. 2) with a = 812,00(10), b = 843,40(10), c = 1179,3(2) pm, α = 100,92(2)°, β = 102,31(2)°, γ = 102,25(2)°.  相似文献   

13.
14.
The preparation and physical properties of the new heterotrinuclear acetates, [Ru2CO(μ3-O)(μ-CH3CO2)6(Py)3] (Ru2Co(II)) and [Ru2Co(μ3-O)(μ-CH3CO2)6(Py)3)l3 (Ru2Co(III), Py = pyridine), are reported. Three reversible one-electron-redox waves are observed at 1.19, 0.40, and ?1.24 V vs Ag/Ag+ electrode for Ru2Co(lI) in CH2Cl2. The complexes of Ru2Co(II) and Ru2Co(III) show an intense visible absorption at 570 (? 5950 M?1 cm?1) and 551 nm (? 7240 M?1 cm?1), respectively. The magnetic susceptibilities of both complexes were also measured from 4.2 to 300 K. The resulting least-squares fit parameters for Ru2Co(II) areJRuCo = ?9 cm?1, JRuRu = ?22 cm?1, gCo, = gRu= 2.19.  相似文献   

15.
Ge2Co6(CO)20: A Ge‐Co Cluster Compound from Solubilized GeBr The Ge‐Co cluster Ge2Co6(CO)20 is synthesized from a reaction of a GeBr solution with Co2(CO)8. Isolation of suitable crystals allows the determination of the crystal structure of Ge2Co6(CO)20, being the lacking member in the row GeCo4(CO)14 – Ge2Co6(CO)20 – Ge3Co8(CO)26.  相似文献   

16.
Reaction of PdPtCl2(dppm)2 with Co(CO)4? or Mn(CO)5? affords the tetrametallic clusters PdPtCo2(CO)7(dppm)2 and PdPtMn2(CO)9(dppm)2. The cobalt cluster reacts with iodide to give PdPtCoI(CO)3(dppm)2 which upon reaction with Fe(CO)3NO? or Mn(CO)5? yields PdPtFeCo(CO)6NO(dppm)2 and PdPtMnCo(CO)8(dppm)2, respectively.  相似文献   

17.
Heteronuclear Coordination Compounds with Metal—Metal Bonds. VIII. New Heterodinuclear Complexes with Bonds between Copper(I) and Manganese(?I), Iron(?I), or Cobalt(?I) [(en)Cu? Mn(CO)5] ( 1a ), [(dien)Cu? Mn(CO)5] ( 1b ), [(en)Cu? Fe(CO)3(NO)] ( 2a ), [(dien)Cu? Fe(CO)3(NO)] ( 2b ), [(en)Cu? Co(CO)4] ( 3a ), and [(dien)Cu? Co(CO)4] ( 3b ) are new heterobinuclear metal—metal bonded complexes. The geometry of the [Mn(CO)5]?, [Fe(CO)3(NO)]?, and [Co(CO)4]? ions is distorted only to a less extend in accord with a heteropolar bond to copper.  相似文献   

18.
The electrochemical behavior of the clusters PhM′Co3(CO)n (M′ = Si, n = 11 and M′ = Sn, n = 12) has been examined via cyclic voltammetry in CH2Cl2 solution. In both cases the radical anions PhM′Co3(CO)n? are unstable, rearranging to Co(CO)4 and other products. However, for the silicon compound, where there is one formal cobalt—cobalt bond, the radical anion is sufficiently stable to allow for detection of anion reoxidation at medium scan speeds. The half-life of PhSiCo3(CO)11? has been calculated as 2.3 s at 25°C.  相似文献   

19.
Reactions of oxygenated cobalt(II) complexes. IX. Oxidative properties of tetrakis(ethylenediamine)-μ-peroxo-μ-hydroxo-dicobalt(III)
  • 1 VIII s. [1].
  • [(en)2Co(O2, OH)Co(en)2]3+ ( a ) reacts with I? in acidic aqueous solution according to: CoIII(O2, OH)CoIII + 21? + 5H+ ? 2CoIII + 3H2O + I2. Using I? in excess first order rate constants are obtained which, to a first approximation, are independent of [I?]. Comparison with kinetic data of deoxygenation of [(en)2Co(O2, OH)Co(en)2]3+ under analogous conditions suggests that both reactions have the same rate determining step. The singly bridged species [(en)2(H2O)CoO2Co(H2O) (en)2]4+ is shown to be the reactive intermediate in the iodide oxidation (Schema 2).  相似文献   

    20.
    The complex (DMPP)Fe2(CO)7 in which DMPP (1-phenyl-3,4-dimethylphosphole) is η4-coordinated with Fe(CO)3 through its diene and η1-coordinated with Fe(CO)4 through its phosphorus atom is selectively decomplexed at phosphorus to give (DMPP)Fe(CO)3 by reaction with AlCl3 followed by NH4OH. This new η4-complex (DMPP)Fe(CO)3 can be oxidized, sulfurized and quaternized at phosphorus by H2O2, S8, and PhCH2Br and MeI, respectively, as an ordinary phosphine without decomplexation of the diene. As a free phosphole, this complex also gives a ring-expanded product by reaction with benzoyl chloride, water and Et3N. In the presence of some metallic salts such as (PhCN)2PdCl2, it loses CO to give the bimetallic sandwich [(DMPP)Fe(CO)2]2. It can also give some new bimetallic complexes such as [(DMPP)Fe(CO)3]W(CO)5 by complexation of the phosphorus lone pair by W(CO)5(THF).  相似文献   

    设为首页 | 免责声明 | 关于勤云 | 加入收藏

    Copyright©北京勤云科技发展有限公司  京ICP备09084417号