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1.
Biferrocenium tetrabromoferrate, [(C5H5)Fe(C5H4)-(C5H4)Fe(C5H5)]FeBr4 (1) obtained as a by-product in the synthesis of biferrocenium trihalide salts, crystallizes in the noncentrosymmetric orthorhombic space group, P212121: (at 296 K) a 7.492(2), b 9.903 (2), c 31.604(9) Å, V 2345(1) Å3, and Z = 4. The cation, similar to other structurally characterized biferrocenium salts, adopts a trans-configuration, but, in contrast, possesses no crystallographically imposed symmetry relating the two ferrocenyl environments. Different average Fe-ring distances at the two environments: Fe(1), 2.02(2) and Fe(2), 2.08(2) Å are typical of iron(II) and iron(III) states, respectively, indicating the presence of trapped oxidation states. Interionic contacts are both shorter and more numerous for the iron(III) ferrocenyl fragment than for the iron(II) fragment. Both ferrocenyl units have non-eclipsed ring configurations, with a staggering angle of 6.5(3)° at Fe(1) and 23.5(3)° at Fe(2). The FeBr4 counterion is tetrahedral and ordered.  相似文献   

2.
The crystal structures and absolute configurations of (η5-C5H5)-CoI(NC4H3-C(R)=N(S)-CH(CH3)(C6H5)) (R = H, compound I; R = CH3, compound II) have been determined by single crystal X-ray diffraction. Crystals of compound I are orthorhombic, with a 11.084(6), b 12.107(6) and c 13.121(7) Å, space group P212121 and d (calcd, Z = 4) 1.69 g cm?3 The structure was solved by the Patterson technique and refined with use of full matrix least-squares methods to R(F) = 0.031 and Rw(F) = 0.028. Compound II is nearly isomorphous and isostructural; a 11.246(6), b 11.923(6) and c 13.370(7) Å, d(calc., Z = 4) 1.71 g cm?3 and was refined to the final agreement factors of R(F) = 0.044 and Rw(F) = 0.035. The Co atom has a distorted tetrahedral coordination, with Co-I 2.595(2) for I and 2.607(2) Å for II; Co-(η5-C5H5 ring centroid) 1.681(4) and 1.703(5) Å; Co-N(pyrrole) 1.905(9) and 1.885(9) Å; Co-N(imine) 1.971(8) and 2.003(9) Å, all the parameters being well within values found in the literature. The configuration around the chiral carbon of the phenylethylamine is S for both compounds, whereas the configuration around the metal is R in I and S in II. The different metal configurations in I and II have their origin in the two different substituents (R = H, CH3) at the imine carbon atoms of the chelate ring, which induce completely different conformations of the (S)-CH(CH3)(C6H5) moiety in the two complexes. For both compounds the thermodynamically less stable isomer is enriched upon crystallization. Also, for compound I the solution and solid state conformations are almost opposite to each other, the conformation in the solid reflecting intramolecular interactions (phenyl/C5H5 attraction).  相似文献   

3.
李纲  李子峰  吴静霞  王利鹏  侯红卫 《化学学报》2007,65(14):1363-1367
Pb(OAc)2•3H2O, 3-二茂铁-2-丁烯酸钠以及1,10-邻菲啰啉在甲醇中反应得到了铅的配位聚合物: [Pb(m-OOCCH=C(CH3)Fc)(m2-OOCCH=C(CH3)Fc)(phen)]n (Fc=(h5-C5H5)Fe(h5-C5H4); phen=1,10-邻菲啰啉). 单晶测试表明: 每个铅离子为六配位, 其中4个氧原子来自4个3-二茂铁-2-丁烯酸根, 另2个氮原子来自邻菲啰啉; 相邻的铅离子通过3-二茂铁-2-丁烯酸根的单齿和双齿氧原子桥连形成了一个无限的一维长链. 研究了标题化合物在DMF溶液中的电化学性能.  相似文献   

4.
1,1′-Disubstituted Titanocene Dithiolene Chelates of Type (η5-Me3EC5H4)2Ti(S2C2R2) (E = C, Si, Ge) Reaction of the titanocene dichlorides (η5-Me3EC5H4)2TiCl2 (E = C, 1a ; E = Si, 1b ; E = Ge, 1c ) with the 1,2-dithiolates (NaS)2C2H2, (NaS)2C2(CN)2 or (LiS)2C6H3Me-4 gave the new titanocene dithiolene chelates (η5-Me3EC5H4)2Ti(S2C2H2) ( 2a–c ), (η5-Me3EC5H4)2Ti[S2C2(CN)2] ( 3a–c ) and (η5-Me3EC5H4)2Ti(S2C6H3Me-4) ( 4a–c ). These have been characterized by 1H NMR, IR, and mass spectroscopy, and have been compared with the unsubstituted η5-C5H5 analogues 2d, 3d and 4d . Activation energies for the chelate ring inversion in solution of 2a–c, 3a–d and 4a–c have been estimated by temperature-dependent 1H NMR spectroscopy.  相似文献   

5.
Sodium cyanoborohydride has been found to be very effective for the conversion of [(h5-C5H5)Fe(CO)2(h2-alkene)]+BF4? complexes to the corresponding h1-alkyl derivatives.  相似文献   

6.
Series of 2-benzoxazole-1,10-phenanthrolines (L1-L4) and 2-oxazoline-1,10-phenanthrolines (L5-L8) were synthesized and used as tridentate N^N^N ligands in coordinating with metal (nickel, cobalt or iron) chlorides. Their metal complexes, nickel(II) (Ni1-Ni8), cobalt(II) (Co1-Co8) and iron(II) (Fe1-Fe8), were characterized by elemental and IR spectroscopic analyses. The molecular structures of the ligand L2 and the complexes Ni3, Co1, Co3 and Fe2 have been determined by the single-crystal crystallography. The nickel complex Ni3 and iron complex Fe2 display an octahedral geometry, whereas cobalt complex Co1 is with a distorted bipyramidal geometry and Co3 as square pyramidal geometry. At 10 atm ethylene, all the complexes showed good activities in ethylene dimerization upon activation with appropriate aluminum cocatalysts; the nickel complexes gave the activity up to 3.11 × 106 g mol−1(Ni) h−1 upon activation with diethylaluminum chloride (Et2AlCl), meanwhile the cobalt and iron complexes showed activities up to 1.51 × 106 g mol−1(Co) h−1 and 1.89 × 106 g mol−1(Fe) h−1, individually, upon activation with modified methylaluminoxane (MMAO).  相似文献   

7.
Summary By reaction of the [1]zirconocenophane(CH)3)2Si(C5H4)2ZrCl2 with equivalent amounts of LiEt 3BH and sulfur, (CH3)2Si(C5H4)2ZrS5 can be prepared as chelate complex. The structure of this ZrS5 chelate is discussed on the basis of its1H NMR spectrum.
  相似文献   

8.
Electron-rich Phenyl Complexes of Transition Metals. II. Li4Co2(C6H5)4 · 4THF, Li4Co2(C6H5)4 · 3 Dioxan and Li3Co(C6H5)2(LiC6H5) · 5THF, the First Complexes with a Bis(phenyl)-cobalt(0)- and -cobalt(-I) Unity . Li2CoII(C6H5)4 · 4THF reacts spontaneously in benzene by splitting off of two phenyl radicals to a dimeric bis(phenyl) cobalt(0) complex which has been isolated as a THF and a dioxan adduct Li4Co2(C6H5)4 · 4THF and Li4Co2(C6H5)4 · 3 Dioxan, respectively. Reduction with lithiumphenyl in ether gives a phenyl cobalt(-I) complex Li4Co(C6H5)3 · 5THF containing besides σ-bonded phenyl anions lithium phenyl coordinated to cobalt in a π-complex like manner, proved by means of 13C? NMR-spectroscopy. The stabilization of the low oxidation states is explained by coordination of the lithium ions to cobalt by multiple center bonds, and for each compound a plausible structure is derived.  相似文献   

9.
The crystal and molecular structure of [diethylbis(1-pyrazolyl)borato]methyl(1-phenylpropyne)platinum(II), ([(C2H5)2B(N2C3H3)2](CH3)Pt(C6H5CCCH3)), has been determined by a single crystal X-ray diffraction study using diffractometer techniques. The compound crystallizes in the monoclinic space group P21/c with a = 13.239(6), b = 11.077(5), c = 15.619)7) Å and β = 114.53(2)°. The observed density of 1.71(2) g cm?3 agrees well with the calculated value, 1.687 g cm?3, assuming four molecules in the cell. A conventional agreement factor of 0.036 was obtained by least-squares refinement on F using 3289 observations and 194 variables. The coordination about the platinum atom is square planar, if the acetylene is assumed to occupy one coordination site. The substituents of the acetylene are cis-bent away from the Pt atom, the methyl substituent by 17.7(1.0)°, and the phenyl substituent by 21.2(9)°. The coordinated triple bond length is 1.227(10) Å. These results indicate that the acetylene is moderately perturbed on coordination, consistent with the observation that Δν(CC) is 211 cm?1. The conformation of the ring formed by the bidentate polypyrazolylborate ligand is that of a “shallow” boat. One of the methylene H atoms on the ethyl substituents on the polypyrazolylborate ligand when placed in an idealized position is 2.65 Å distant from the Pt atom.  相似文献   

10.
Reactions of Fe+ and FeL+ [L=O, C4H6, c-C5H6, C5H5, C6H6, C5H4(=CH2)] with thiophene, furan, and pyrrole in the gas phase by using Fourier transform mass spectrometry are described. Fe+, Fe(C5H5)+, and FeC6H 6 + yield exclusive rapid adduct formation with thiophene, furan, and pyrrole. In addition, the iron-diene complexes [FeC4H 6 + and Fe(c-C5H6)+], as well as FeC5H4(=CH2)+ and FeO+, are quite reactive. The most intriguing reaction is the predominant direct extrusion of CO from furan by FeC4H6 +, Fe(c-C5H6)+, and FeC5H4(=CH2)+. In addition, FeC4H 6 + and Fe(c-C5H6)+ cause minor amounts of HCN extrusion from pyrrole. Mechanisms are presented for these CO and HCN extrusion reactions. The absence of CS elimination from thiophene may be due to the higher energy requirements than those for CO extrusion from furan or HCN extrusion from pyrrole. The dominant reaction channel for reaction of Fe(c-C5H6)+ with pyrrole and thiophene is hydrogen-atom displacement, which implies DO(Fa(N5H5)+-C4H4X)>DO(Fe(C5H5)+-H)=46±5 kcal mol?1. DO(Fe+-C4H4S) and DO(Fe+-C4H5N)=DO(Fe+-C4H6)=48±5 kcal mol?1. Finally, 55±5 kcal mol?1=DO(Fe+-C6H6)>DO(Fe+-C4H4O)>DO(Fe+-C2H4)=39.9±1.4 kcal mol?1. FeO+ reacts rapidly with thiophene, furan, and pyrrole to yield initial loss of CO followed by additional neutral losses. DO(Fe+-CS)>DO(Fe+-C4H4S)≈48±5 kcal mol?1 and DO(Fe+-C4H5N)≈48±5 kcal mol?1>DO(Fe+-HCN)>DO(Fe+-C2H4)=39.9±1.4 kcal mil?1.  相似文献   

11.
Conclusions The authors have synthesized anilinium chloranilate (NH3C6H5)2(C6O4Cl2) (I) and acid ammonium chloranilate dihydrate NH4H5O2(C6O4C12) (II). By x-ray structural analysis they have established their crystal structures. In crystals of NH4H5O2(C6O4Cl2) they find the ion H5O 2 + with the unusual O-H-O bond length of 2.81 A. The anions of chloranilic acid in crystals (I) and (II) have equal charges but different structures.Translated from IzvestiyaAkademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 487–489, March, 1981.  相似文献   

12.
Kinetic studies of reactions of the MoMo bonded complex (h5-C5H5)2Mo2(CO)6 in decalin show that it undergoes reversible homolytic fission and that the activation enthalpy required to break the MoMo bond is 135.9 ± 2.2 kJ mol?1.  相似文献   

13.
The hydrolysis of (C2H5)2Sn2+, (C2H5)3Sn+ and (n‐C3H7)3Sn+ has been studied, by potentiometric measurements ([H+]‐glass electrode), in NaNO3, NaCl, NaCl/Na2SO4 mixtures and in a synthetic seawater (SSWE), as an ionic medium simulating the major composition of natural seawater, at different ionic strengths (0 ≤ I ≤ 5 mol dm?3) and salinities (15 ≤ S ≤ 45), and at t = 25 °C. Five hydrolytic species for (C2H5)2Sn2+, three for (C2H5)3Sn+ and two for (C3H7)3Sn+ are found. Interactions with the anion components of SSWE, considered as single‐salt seawater, are determined by means of a complex formation model. A predictive equation for the calculation of unknown hydrolysis constants of trialkyltin(IV) cations, such as tributyltin(IV), in NaNO3, NaCl, and SSWE media at different ionic strengths is proposed. Equilibrium constants obtained are also used to determine the interaction parameters of Pitzer equations. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   

14.
The structure of a titanium aluminium hydride complex of composition [(C5H5)2TiAlH4]2(CH3)2NC2H4N(CH3)2C6H6 has been determined by X-ray diffraction. The complex forms triclinic crystals with unit cell dimensions a = 8.406(2), b = 10.117(2), c = 11.269(3) Å; α = 112.01(2)°, β = 109.25(2)°, γ = 87.04(2)°, space group P1, Z = 2 and density d = 1.21 g/cm3. The structure was refined to give a discrepancy index R = 0.056. The crystals are composed of centrosymmetric molecules of (Cp2TiAlH4)2TMEDA (Cp = η5-cyclopentadienyl) and molecules of crystal benzene. Two moieties of Cp2TiH2AlH2 are linked by a tetramethylethylenediamine molecule (rAlN 2.11 Å). The aluminium atom is bonded to a titanium atom by a double hydride bridge (rAlH b = 1.8, 1.6 Å, rTiH b = 1.6 Å), and has trigonal bipyramidal stereochemistry, [H4N] (rAlH t = 1.6 Å).  相似文献   

15.
Synthetic methods for several novel phosphoramidate compounds containing the P(O)NHC(O) bifunctional group were developed. These compounds with the general formula R1C(O)NHP(O)(N(R2)(CH2C6H5))2, where R1 = CCl2H, p-ClC6H4, p-BrC6H4, o-FC6H4 and R2 = hydrogen, methyl, benzyl, were characterized by several spectroscopic methods and analytical techniques. The effects of phosphorus substituents on the rotation rate around the P–Namine bond were also investigated. 1H NMR study of the synthesized compounds demonstrated that the presence of bulky groups attached to the phosphorus center and electron withdrawing groups in the amide moiety lead to large chemical-shift non-equivalence (ΔδH) of diastereotopic methylene protons. The crystal structures of CCl2HC(O)NHP(O)(NCH3(CH2C6H5))2, p-ClC6H4C(O)NHP(O)(NCH3(CH2C6H5))2, CCl2HC(O)NHP(O)(N(CH2C6H5)2)2 and p-BrC6H4C(O)NHP(O)(N(CH2C6H5)2)2 were determined by X-ray crystallography using single crystals. The coordination around the phosphorus center in these compounds is best described as distorted tetrahedral and the P(O) and C(O) groups are anti with respect to each other. In the compound Br-C6H4C(O)NHP(O)(N(CH2C6H5)2)2 (with two independent molecules in the unit cell), two conformers are connected to each other via two different N–H?O hydrogen bonds forming a non-centrosymmetric dimer. In the crystalline lattice of other compounds, the molecules form centrosymmetric dimers via pairs of same N–H?O hydrogen bonds. The structure of CCl2HC(O)NHP(O)(N(CH2C6H5)2)2 reveals an unusual intramolecular interaction between the oxygen of CO group and amine nitrogen.  相似文献   

16.
The 31P NMR spectra of C6H5XCr(CO)2P(C6H5)3 (X = H, CH3, OCH3, N(CH3)2, COOCH3) (I), p-C6H4X2Cr(CO)2P(C6H5)3 (X = COOCH3)(II) and C6H3X3Cr(CO)2P(C6H5)3 (X = CH3) (III) complexes in neutral and acidic media were investigated. The protonation of complexes I and III in trifluoroacetic acid results in the greater upfield shielding of 31P{1H} signal. In this case the complexes I (X = H, CH3, OCH3) are completely protonated at the metal, complex I (X = COOCH3)is partially protonated, while no protonation occurs in the case of complex II.Temperature-dependence of the 31P{1H} NMR spectra was investigated for complexes I (X = H, OCH3) in a 1/10 mixture of trifluoroacetic acid and toluene and for complexes I (X = COOCH3) and II in trifluoroacetic acid. The degree of protonation was found to increase with decreasing temperature.  相似文献   

17.
Chloroselenates(IV): Synthesis, Structure, and Properties of [As(C6H5)4]2Se2Cl10 and [As(C6H5)4]Se2Cl9 The Se2Cl102? and Se2Cl9? anions were prepared, as the first dinuclear haloselenates(IV), from the reaction of (SeCl4)4 with stoichiometric quantities of chloride ions in POCl3 solutions; they were isolated as yellow crystalline As(C6H5)4+ salts. Complete X-ray structural analyses at ?130°C of [As(C6H5)4]2Se2Cl10 ( 1 ) (space group P1 , a = 10.296(7), b = 11.271(6), c = 12.375(8) Å, = 74.17(5)°, α = 81.38(5)°, β = 67.69(4)°, V = 1276 Å3) and of [As(C6H5)4]Se2Cl9 ( 2 ) (space group P21/n, a = 12.397(5), b = 17.492(6), c = 14.235(4) Å, α 93.25(3)°, V = 3082 Å3) show in both cases two distorted octahedral SeCl6 groups connected through a common edge in 1 and a common face in 2 . The terminal Se? Cl bonds (average 2.317 Å in 1 , 2.223 Å in 2 ) are much shorter than the Se? Cl bridges (av. 2.661 Å in 1 , 2.652 Å in 2 ). The stereochemical activity of the SeIV lone electron pair causes severe distortion of the central Se2Cl2 ring in the centrosymmetric Se2Cl102? ion. The vibrational spectra of the anions are reported.  相似文献   

18.
The o‐substituted hybrid phenylphosphines, PPh2(o‐C6H4NH2) and PPh2(o‐C6H4OH), could be deprotonated with LDA or n‐BuLi to yield PPh2(o‐C6H4NHLi) and PPh2(o‐C6H4OLi), respectively. When added to a solution of (η5‐C5H5)Fe(CO)2I at room temperature, these two lithiated reagents produce a chelated neutral complex 1 (η5‐C5H5)Fe(CO)[C(O)NH(o‐C6H4)PPh2C,P‐η2] for the former and mainly a zwitterionic complex 2 , (η5‐C5H5)Fe+(CO)2[PPh2(o‐C6H4O?)] for the latter. Complex 1 could easily be protonated and then decarbonylated to give 4 [(η5‐C5H5)Fe(CO){NH2(o‐C6H4)PPh2N,P‐η2}+]. Complexes 1 and 4‐I have been crystallographically characterized with X‐ray diffraction.  相似文献   

19.
Spectroscopic Investigations of the Iron(II) Nitrosodicyanomethanide and Nitrosocarbamoylcyanomethanide Complexes [Fe(NOC(CN)2)2(C5H5N)4] and [Fe(NOC(CN)C(O)NH2)2(C5H5N)2] The syntheses of new iron(II) complexes of the nonlinear pseudohalides [NOC(CN)2]? and [NOC(CN)C(O)NH2]? is reported. The Structures of the compounds are discussed on the basis of IR, Mößbauer, 13C, and 14N NMR spectra as well as of the results of magnetic measurements.  相似文献   

20.
[(C6H5CH2C5H4)2GdCl.THF]2 (1) and (C6H5CH2C5H4)2ErCl.THF (2) were prepared by the reaction of LnCl3 (Ln? Gd, Er) with benzylcyclopentadienyl sodium in THF and characterized by elemental analysis, IR, 1H NMR, 13C NMR, MS and thermal gravimetry. The crystal structures of both compounds were determined. Complex 1 is dimeric and its structure belongs to the monoclinic, P21/c space group with a=1.1432(2), b=1.2978(2), c=1.7604(3) nm, β=108.75(2), V=2.4732(9) nm3, Z=2(four monomers), Dc“1.54 g.cm?3. R=0.0342 and Rw“0.0362. Complex 2 is monomer and its structure belongs to the orthorhombic, P212121 space group with a=0.8645(2), b=1.1394(3), c=2.5289(4) nm, V=2.4919(9) nm3, Z=4, Dc“1.56 g.cm?3. R=0.0514, Rw“0.0529. The determination of the crystal structure shows that in complex 1 the benzyl groups on the cyclopentadienyls coordinated to Gd3+ are located in the opposite direction (139°); in complex 2 the benzyl groups on the cyclopentadienyls coordinated to Er3+ are located in the same direction (6.5°).  相似文献   

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