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1.
The enhanced reactivity of [WF5]+ over WF6 has been exploited to access a neutral derivative of elusive WF5. The reaction of WF6(NC5H5)2 with [(CH3)3Si(NC5H5)][O3SCF3] in CH2Cl2 results in quantitative formation of trigonal-dodecahedral [WF5(NC5H5)3]+, which has been characterised as its [O3SCF3] salt by Raman spectroscopy in the solid state and variable-temperature NMR spectroscopy in solution. The salt is susceptible to slow decomposition in solution at ambient temperature via dissociation of a pyridyl ligand, and the resultant [WF5(NC5H5)2]+ is reduced to WF5(NC5H5)2 in the presence of excess C5H5N, as determined by 19F NMR spectroscopy. Pentagonal-bipyramidal WF5(NC5H5)2 was isolated and characterised by X-ray crystallography and Raman spectroscopy in the solid state, representing the first unambiguously characterised WF5 adduct, as well as the first heptacoordinate adduct of a transition-metal pentafluoride. DFT-B3LYP methods have been used to investigate the reduction of [WF5(NC5H5)2]+ to WF5(NC5H5)2, supporting a two-electron reduction of WVI to WIV by nucleophilic attack and diprotonation of a pyridyl ligand in the presence of free C5H5N, followed by comproportionation to WV.  相似文献   

2.
The crystal structure of the title complex, (C8H10N)2(C5H6N)[BiI6], contains discrete [BiI6]3? anions, and (HNC5H5)+ and (CH3COCH2NC5H5)+ cations separated by normal van der Waals contacts. The [BiI6]3? anion has the Bi atom on an inversion centre. The (HNC5H5)+ cation also lies about an inversion centre and is disordered. The (CH3COCH2NC5H5)+ cation lies in a general position.  相似文献   

3.
Thallium [1-(p-tolylimino)-2-methylpropyl]cyclopentadienide, Tl[C5H4C(=NC6H4CH3)CH(CH3)2], was prepared and treatment of the salt with [{PdCl2(PREt2)}2] (R = Ph and Et) yielded mononuclear palladium(II) complexes, [Pd{η5-C5H4C(=NC6H4CH3)CH(CH3)2}Cl(PREt2)], with an imidoyl-substituted η5-cyclopentadienyl group. In addition, [Pd(η5-C5H4-COY)Cl(PPhEt2)] (Y = CH3 and OCH3) complexes were obtained from the sodium salts of their substituted cyclopentadienyl groups. These new compounds were characterized by means of 1H and 13C NMR and IR spectroscopy.  相似文献   

4.
Monocationic bis‐allyl complexes [Ln(η3‐C3H5)2(thf)3]+[B(C6X5)4]? (Ln=Y, La, Nd; X=H, F) and dicationic mono‐allyl complexes of yttrium and the early lanthanides [Ln(η3‐C3H5)(thf)6]2+[BPh4]2? (Ln=La, Nd) were prepared by protonolysis of the tris‐allyl complexes [Ln(η3‐C3H5)3(diox)] (Ln=Y, La, Ce, Pr, Nd, Sm; diox=1,4‐dioxane) isolated as a 1,4‐dioxane‐bridged dimer (Ln=Ce) or THF adducts [Ln(η3‐C3H5)3(thf)2] (Ln=Ce, Pr). Allyl abstraction from the neutral tris‐allyl complex by a Lewis acid, ER3 (Al(CH2SiMe3)3, BPh3) gave the ion pair [Ln(η3‐C3H5)2(thf)3]+[ER31‐CH2CH?CH2)]? (Ln=Y, La; ER3=Al(CH2SiMe3)3, BPh3). Benzophenone inserts into the La? Callyl bond of [La(η3‐C3H5)2(thf)3]+[BPh4]? to form the alkoxy complex [La{OCPh2(CH2CH?CH2)}2(thf)3]+[BPh4]?. The monocationic half‐sandwich complexes [Ln(η5‐C5Me4SiMe3)(η3‐C3H5)(thf)2]+[B(C6X5)4]? (Ln=Y, La; X=H, F) were synthesized from the neutral precursors [Ln(η5‐C5Me4SiMe3)(η3‐C3H5)2(thf)] by protonolysis. For 1,3‐butadiene polymerization catalysis, the yttrium‐based systems were more active than the corresponding lanthanum or neodymium homologues, giving polybutadiene with approximately 90 % 1,4‐cis stereoselectivity.  相似文献   

5.
The fast atom bombardment mass spectra of a series of neutral methanide and ionic carbene platinum(II) complexes of formula dPePtL2 and [dPePt(LH)2](BF4)2 (dPe = (C6H5)2PCH2CH2P(C6H5)2; L = ? C(OCH3)-NCH3, ? C(OCH3) ? NC6H11, ? C(OCH3) ? NC6H4p ? CH3), respectively are reported. Glycerol, 3-mercapto-1,2-propanediol, bis (2-hydroxyethyl)sulphide, 3-nitrobenzyl alcohol, and 2,4-di-tert-pentylphenol have been used as matrices. Neutral and ionic derivatives containing the same ligand behave similarly and give the same quasi-molecular [dPePtL(L + H)]+ ion by different primary processes. Stepwise breakdown of the ligands L with retention or further loss of atoms or molecules of hydrogen is observed for all these complexes, followed by ejection of radicals from the dPe ligand. Elimination of CH3OH from [dPePtL(L + H)]+ also occurs. The highest ionic yields of both neutral methanide and ionic carbene complexes are observed in 3-mercapto-1,2-propanediol, in bis(2-hydroxyethyl)sulphide, and in 3-nitrobenzyl alcohol with respect to glycerol. The [dPePt(LH)2]2+ doubly charged ions are present in the spectra obtained with 3-nitrobenzyl alcohol and are rather strong when L is ? C(OCH3) ? NCH3 and ? C(OCH3) ? NC6H4p ? CH3. Substitution of ligands L with a molecule or with a fragment of a sulphur containing matrix takes place very seldom with this series of complexes.  相似文献   

6.
We have reported herein the synthesis of three new Cu(II) complexes of tri- and tetradentate Schiff base ligands containing N3 or N4 donor set along with terminal NNN or SCN ligands: [L1Cu(NCS)]ClO4 (1), [L2Cu(NCS)2] (2) and [L3Cu(NNN)]ClO4 (3) [L1 = NC5H4C(CH3)=N(CH2)3N=C(CH3)C5H4N, L2= Me2N–(CH2)3–N=C(CH3)C5H4N and L3 = NC5H4CH=N–(CH2)4–N=CHC5H4N]. The complexes have been systematically characterised by elemental, spectroscopic and electrochemical techniques. Antimicrobial activities of the Schiff base ligands and their metal complexes have been studied using the disc diffusion method on the strains of Candida tropicalis and Bacillus megaterium. Structures of all the complexes have been unequivocally established from single crystal X-ray diffraction analyses that show the monomeric units containing a five-coordinated copper center in highly distorted square pyramidal geometry with thiocyanate or azide anion coordinated as terminal ligand. The complexes 1 and 3 crystallise in monoclinic (P21/c) and 2 in triclinic (P-1) space group, respectively.  相似文献   

7.
A convenient and efficient method for the synthesis of pyrazolo[3,4‐d]pyrimidin‐4‐ones via heterocyclization reaction of 5‐amino‐1H‐pyrazole‐4‐carboxamides with triethyl orthoesters using two Br?nsted‐acidic ionic liquids, 3‐methyl‐1‐(4‐sulfonic acid)butylimidazolium hydrogen sulfate [MIM+(CH2)4SO3H][HSO4?] or N‐(4‐sulfonic acid)butyl triethylammonium hydrogen sulfate [Et3N+(CH2)4SO3H][HSO4?], as efficient homogeneous catalysts under solvent‐free conditions is described.  相似文献   

8.
The positive-ion mass spectra of the following organonitrogen derivatives of metal carbonyls are discussed: (i) The compounds NC5H4CH2Fe(CO)2C5H5, NC5H4CH2COMo(CO)2C5H5, NC5H4CH2W(CO)3C5H5, NC5H4CH2COMn(CO)4, C5H10NCH2CH2Fe(CO)2C5H5, (CH3)2NCH2CH2COFeCOC5H5 and (CH3)2NCH2CH2COMn(CO)4 obtained from metal carbonyl anions and haloalkylamines, (ii) The isocyanate derivative C5H5Mo(CO)3CH2NCO; (iii) The arylazomolybdenum derivatives RN2Mo(CO)2C5H5 (R ? phenyl, p-tolyl, or p-anisyl); (iv) The compound (C6H5N)2COFe2(CO)6 obtained from Fe3(CO)12 and phenyl isocyanate; (v) The N,N,N′,N′-tetramethylethylenediamine complex (CH3)2NCH2CH2N(CH3)2W(CO)4. Further examples of eliminations of hydrogen, CO, and C2H2 fragments were noted. In addition evidence for the following more unusual processes was obtained: (i) Elimination of HCN fragments from the ions [NC5H4CH2MC5H5]+ to give the ions [(C5H5)2M]+ (M ? Fe, Mo and W); (ii) Conversion of C5H5Mo(CO)3CH2NCO to C5H5Mo(CO)2CH2NCO within the mass spectrometer; (iii) Elimination of N2 from [RN2MoC5H5]+ to give [RMoC5H5]+; (iv) Novel eliminations of HNCO, FeNCO, and C6H5NC fragments in the mass spectrum of (C6H5N)2COFe2(CO)6; (v) Facile dehydrogenation of the N,N,N′,-N′-tetramethylethylenediamine ligand in the complex (CH3)2NCH2CH2N(CH3)2W(CO)4.  相似文献   

9.
Transition‐metal hexafluorides do not exhibit fluoride‐ion donor properties in the absence of donor ligands. We report the first synthesis of donor‐stabilized [MF5]+ derived from a transition‐metal hexafluoride via fluoride‐ion abstraction using WF6(L) (L=2,2′‐bipy, 1,10‐phen) and SbF5(OSO) in SO2. The [WF5(L)][Sb2F11] salts and [WF5(1,10‐phen)][SbF6]?SO2 have been characterized by X‐ray crystallography, Raman spectroscopy, and multinuclear NMR spectroscopy. The reaction of WF6(2,2′‐bipy) with an equimolar amount of SbF5(OSO) reveals an equilibrium between [WF5(2,2′‐bipy)]+ and the [WF4(2,2′‐bipy)2]2+ dication, as determined by 19F NMR spectroscopy. The geometries of the cations in the solid state are reproduced by gas‐phase geometry optimizations (DFT‐B3LYP), and NBO analyses reveal that the positive charges of the cations are stabilized primarily by compensatory σ‐electron donation from the N‐donor ligands.  相似文献   

10.
The preparation of (borinato)(cyclobutadiene)cobalt complexes from the reactions of Co(C5H5BR)(1,5-C8H12) with acetylenes C2R′2 and of [C4(CH3)4]Co(CO)2I with Tl(C5H5BR) (R,R′ = CH3, C6H5) is described.In electrophilic substitution reactions Co(C5H5BCH3)[C4(CH3)4] (IVa) is more reactive than ferrocene. CF3CO2D effects H/D-exchange in the α-position of the borabenzene ring within a few minutes at ambient temperature and in the γ-position within less than four hours Friedel-Crafts acetylation with CH3COCl/AsCl3 in CH2Cl2 affords the 2-acetyl and the 2,6-diacetyl derivative of IVa. With the more active catalyst AlCl3, ring-member substitution is effected to give cations [Co(arene)C4(CH3)4]+ (arene = C6H5CH3, 2-CH3C6H4COCH3). Vilsmeier formylation gives the 2-formyl derivative of IVa. The acyl derivatives Co(2-R1CO-6-R2C5H3BCH3)[C4(CH3)4] (R1 = CH3, R2 = H, CH3CO and R1 = R2 = H) transform to the corresponding cations [Co(ortho-R1R2C6H4)C4(CH3)4]+ in superacidic media. The mechanistic relationship between acylation and ring-member substitution is discussed in detail.  相似文献   

11.
Stabilization of the central atom in an oxidation state of zero through coordination of neutral ligands is a common bonding motif in transition‐metal chemistry. However, the stabilization of main‐group elements in an oxidation state of zero by neutral ligands is rare. Herein, we report that the transamination reaction of the DAMPY ligand system (DAMPY=2,6‐[ArNH‐CH2]2(NC5H3) (Ar=C6H3‐2,6‐iPr2)) with Sn[N(SiMe3)2]2 produces the DIMPYSn complex (DIMPY=(2,6‐[ArN?CH]2(NC5H3)) with the Sn atom in a formal oxidation state of zero. This is the first example of a tin compound stabilized in a formal oxidation state of zero by only one donor molecule. Furthermore, three related low‐valent SnII complexes, including a [DIMPYSnIICl]+[SnCl3]? ion pair, a bisstannylene DAMPY{SnII[N(SiMe3)2]2}2, and the enamine complex MeDIMPYSnII, were isolated. Experimental results and the conclusions drawn are also supported by theoretical studies at the density functional level of theory and 119Sn Mössbauer spectroscopy.  相似文献   

12.
The preparation of a series of complexes of the types [RhCl(CO)2(L)], [RhCl(cod)(L)] and [Rh(cod)(L)2]ClO4, where L is a ligand incorporating a ferrocenyl group and a pyridine ring is described. Complexes were characterized using NMR, IR and electronic spectroscopy. The electrochemical behaviour of the complexes was examined using cyclic voltammetry. The X-ray structures of three of the complexes, [RhCl(CO)2{NC5H4CNC6H45-C5H4)Fe(η5-C5H5)}], [RhCl(cod)(3-Fcpy)] and [RhCl(cod){3-Fc(C6H4)py}], were determined.  相似文献   

13.
The reactivity of the metalloligand [Pt2(μ-S)2(PPh3)4] with the boron-functionalized alkylating agents BrCH2(C6H4)B(OR)2 (R = H or C(CH3)2) was investigated by electrospray ionization mass spectrometry (ESI-MS) in real time using pressurized sample infusion (PSI). The macroscopic reaction of [Pt2(μ-S)2(PPh3)4] with one mole equivalent of alkylating agents BrCH2(C6H4)B{OC(CH3)2}2 and BrCH2(C6H4)B(OH)2 gave the dinuclear monocationic μ-sulfide thiolate complexes [Pt2(μ-S){μ-SCH2(C6H4)B{OC(CH3)2}2}(PPh3)4]+ and [Pt2(μ-S){μ-S+CH2(C6H4)B(OH)(O?)}(PPh3)4]. The products were isolated as the [PF6]? salt and zwitterion, respectively, and fully characterized by ESI-MS, IR, 1H and 31P NMR spectroscopy, and single-crystal X-ray structure determinations.  相似文献   

14.
In aqueous H2SO4, Ce(IV) ion oxidizes rapidly Arnold's base((p-Me2NC6H4)2CH2, Ar2CH2) to the protonated species of Michler's hydrol((p-Me2NC6H4)2CHOH, Ar2CHOH) and Michler's hydrol blue((p-Me2NC6H4)2CH+, Ar2CH+). With Ar2CH2 in excess, the rate law of the Ce(IV)-Ar2CH2 reaction in 0.100 M H2SO4 is expressed -d[Ce(IV)]/dt = kapp[Ar2CH2]0[Ce(IV)] with kapp = 199 ± 8M?1s?1 at25°C. When the consumption of Ce(IV) ion is nearly complete, the characteristic blue color of Ar2CH+ ion starts to appear; later it fades relatively slowly. The electron transfer of this reaction takes place on the nitrogen atom rather than on the methylene carbon atom. The dissociation of the binuclear complex [Ce(III)ArCHAr-Ce(III)] is responsible for the appearance of the Ar2CH+ dye whereas the protonation reaction causes the dye to fade. In highly acidic solution, the rate law of the protonation reaction of Michler's hydrol blue is -d[Ar2CH+]/dt = kobs[Ar2CH+] where Kobs = ((ac + 1)[H*] + bc[H+]2)/(a + b[H+]) (in HClO4) and kobs= ((ac + 1 + e[HSO4?])[H+] + bc[H+]2 + d[HSO4?] + q[HSO4?]2/[H+])/(a + b[H+] + f[HSO4?] + g[HSO4?]/[H+]) (in H2SO4), and at 25°C and μ = 0.1 M, a = 0.0870 M s, b = 0.655 s, c = 0.202 M?1s?1, d = 0.110, e = 0.0070 M?1, f = 0.156 s, g = 0.156 s, and q = 0.124. In highly basic solution, the rate law of the hydroxylation reaction of Michler's hydrol blue is -d[Ar2CH+]/dt = kOH[OH?]0[Ar2CH+] with kOH = 174 ± 1 M?1s?1 at 25°C and μ = 0.1 M. The protonation reaction of Michler's hydrol blue takes place predominantly via hydrolysis whereas its hydroxylation occurs predominantly via the path of direct OH attack.  相似文献   

15.
Reaction-solution calorimetric studies involving the complexes Ti[η5-C5(CH3)5]2-(CH3)2, Ti[η5-C5(CH3)5]2(CH3), Ti[η5-C5(CH3)5]2(C6H5), Ti[η5-C5(CH3)5]2Cl2, and Ti[η5-C5(CH3)5]2Cl, have enabled derivation of titaniumcarbon and titaniumchlorine stepwise bond dissociation enthalpies in these species.  相似文献   

16.
The reaction of IrH3(PPh3)2 with p-substituted aryldiazonium salts gives the compounds [IrH2(NHNC6H4R)(PPh3)2]+BF4- at low temperature (-10°C) and the o-metalated complexes [IrH(NHNC6H3R)(PPh3)2]+BF4- (R  F, OCH3) at 40–50°C. The reactions of the o-metalated complexes with CO, PPh3, NaI and HCl have been studied.  相似文献   

17.
The reactions of Fe(CO)5 or Fe3(CO)12 with NaBEt3H or KB[CH(CH3)C2H5]3H, respectively and treatment of the resulting carbonylates M2Fe(CO)4, M = Na, K with elemental selenium in appropriate ratios lead to the formation of M2[Fe2(CO)6(μ‐Se)2]. Subsequent reactions with organo halides or the complex fragment cpFe(CO)2+, cp = η5‐C5H5 afforded the selenolato complexes [Fe2(CO)6(μ‐SeR)2], R = CH2SiMe3 ( 1 ), CH2Ph ( 2 ), p‐CH2C6H4NO2 ( 3 ), o‐CH2C6H4CH2 ( 4 ) and cpFe(CO)2+ ( 5 ) in moderate to good yields. A similar reaction employing Ru3(CO)12, Se and p‐O2NC6H4CH2Br leads to the formation of the corresponding organic diselenide. The X‐ray structures of 1 , 3 , 4 and 5 were determined and revealed butterfly structures of the Fe2Se2 cores. The substituents in 1 , 3  and 5 adopt different conformations depending on their steric demand. In 4 , the conformation is fixed because of the chelate effect of the ligand. The Fe–Se bond lengths lie in the range 235 to 240 pm, with corresponding Fe–Fe bond lengths of 254 to 256 pm. The 77Se NMR data of the new complexes are discussed and compared with the corresponding data of related complexes.  相似文献   

18.
The reactions of tetraphenylbismuthonium and -stibonium salts Ph4EX (E = Bi, Sb; X = I, OSO2 (C6H3(CH3)2-2,5), OSO2C6H3(OH-4)(COOH-3)) with bismuth triiodide in acetone afford complexes [Ph4Bi]+[PhBi(C5H5N)I3]-, [(Ph4BiO)2S(O){2,5-(CH3)2C6H3S(O)} [Ph2Bi2I6]2–, [Ph4Sb [Bi4I16]4-·2(CH3)2C=O, and [Ph4Sb] 3+ + [Bi5I18]3-, whose structural units, according to the X-ray diffraction data, are tetraphenylbismuthonium (-stibonium) cations and mono-, di-, tetra-, and pentanuclear anions, respectively.  相似文献   

19.
The Reaction of Molybdenum with 2,3-Dihydroxynaphthalene   总被引:1,自引:0,他引:1  
[H2N(CH2)3NH312[MoO2(C10H6O2)2] (1) was synthesized by the 2,3-dihydroxynaphthalene in the mixed solvent of CH3OH, CH3CN reaction of (n-Bu4N)4[Mo8O26] with and 1,3-propanediarnine. (C5HllN2)2- [HeN(CH2)3NH2][MoO2(CloH6O2)2] (2) was obtained by the reaction of Na2MoO4.2H20 with 2,3-dihydroxynaphthalene in the same solvent above. Both of the complexes possess complex anion [Mo(VI)O2(OC10H6O)2]^2- which shows pseudo-octahedrally coordinated fashion, while the counterions are two protonated 1,3-propanediamine in complex 1 and (CsH11N2)^+ in complex 2. (C5H11N2)+ is the byproduct of reaction 2, which results from combination of acetonitrile with 1,3-propanediamine. Packing diagrams of the two complexes are also different. There is anti-parallel-aligned-double-meso-bilayer unit in complex 1. However there are four chiral anions arranged in anticlockwise orientation in complex 2.  相似文献   

20.
The reaction of Mo(η3-C3H4(CH3))(CH3CN)2(CO)2Cl with AgBF4 in THF yields the cationic complex [Mo(η3-C3H4(CH3))(CH3CN)2(CO)2(THF)]+[BF4], 1, whose X-ray structure has been determined. Oxo nucleophiles are capable of replacing the weakly bound THF molecule in 1 and under simultaneous loss of CH3CN the resulting complexes aggregate to oligonuclear compounds. Accordingly, the reactions with NaOMe and KOH yield [Na(THF)4]+[(η3-C3H4(CH3))(CO)2Mo(μ-OCH3)3Mo(CO)23-C3H4(CH3))], 2 and [K(18-crown-6)]+[[Mo(η3-C3H4(CH3))(CO)2]32-OH)33-OH)], 3, which were characterized by means of single crystal X-ray diffraction. Due to fluoride abstraction from BF4 the reaction of 1 with KOH also yields fluorinated derivatives of 3 but incorporation of fluorine in 3 can be avoided if AgO3SCF3 rather than AgBF4 is used to generate the cation of 1. For purposes of comparison the dinuclear complex [K(18-crown-6)]+[[Mo(η3-C3H4(CH3))(CO)2]22-F)3], 4, has been prepared, too, showing fluoride bridges and KF bonding. The chemical properties and the structures of these compounds in solution as well as their role as structural models for intermediates during molybdenum oxide catalysed propene oxidation are discussed.  相似文献   

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