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1.
Summary The preparation and characterization of salts of the [ReO2(CN)4]3–, [ReO(OH)(CN)4]2–, [ReO(H2O)(CN)4], [Re2O3(CN)8]4– and [ReO(NCS)(CN)4]2– species are described. The nature of the protonation reactions of [ReO2(CN)4]3– was established by the successful isolation of these salts.  相似文献   

2.
The reactions of alkyl isocyanides (RNC) and aryl isocyanides (ArNC) with the rhenium halides K2ReX6 (X = Br or I) and Re3X9 (X = Cl, Br or I) have been investigated. When the K2Rex6 salts are treated with neat isocyanide at room temperature, or with isocyanide ligands in polar solvents under reflux conditions, then the homoleptic isocyanide cations [Re(CNR)6]+ or [Re(CNAr)6]+, are isolated. Under less forcing conditions, various rhenium(III) and rhenium(I) species, e.g. [Re(CNCMe3)5I2]+ and Re(CNAr)5I, which may be considered as intermediates on the way to the formation of the homoleptic species, can be obtained. The rhenium(I) complexes Re(CNAr)5I3, which are believed to contain the coordinated triiodide ligand, have also been isolated and characterized. One route to these complexes is through the reaction of Re(CNAr)5I with I2. Reactions of the trinuclear halides Re3X9 (X = Cl, Br or I) with alkyl isocyanides at room temperature are found, in all instances, to provide adducts of the type Re3X9(CNR)3. Under reflux conditions, Re3Cl9 and Re3Cl9(PEtPh2)3 react with Me3CNC to fom products of cluster disruption, viz. [Re(CNCMe3)6]+ and [Re(CNCMe3)4(PEtPh2)2]+, respectively. The spectroscopic and electrochemical properties of complexes derived in this study are reported. These results are compared with those reported previously by Freni et al.  相似文献   

3.
The reactions of the methylhalogenodimethylaminoarsines CH3As-[N(CH3)2]X (X  F, Cl, Br, I) with HY (Y = Cl, Br) yield the methyldihalogenoarsines CH3AsXY. The compounds CH3As[N(CH3)2]X are prepared by the reactions of CH3AsCl2 with HN(CH3)2, CH3As[N(CH3)2]2 with HX (X = Cl, Br) and by exchange reactions between CH3As[N(CH3)2]2 and CH3AsX2 (X = F, Cl, Br, I).  相似文献   

4.
Reaction of N-Trimethylmetal(IVb) Trialkylphosphine Imines with Hydrogen Halides Investigations of the reaction of N-trimethylmetal(IVb)-substituted phosphine imines with hydrogen have been carried out. With one mole of HX phosphonium halides of the general formula [R3P? NH? MMe3]X? (R = CH3, C2H5; M = Si, Ge, Sn; X = Cl, Br, J) are obtained. A second mole of HX causes M? N bond cleavage, yielding aminophosphonium halides, [R3P? NH2]X?.  相似文献   

5.
The phenylimidorhenium(V) complexes [Re(NPh)X3(PPh3)2] (X = Cl, Br) react with the N‐heterocyclic carbene (NHC) 1,3‐diethyl‐4,5‐dimethylimidazole‐2‐ylidene (LEt) under formation of the stable rhenium(V) complex cations [Re(NPh)X(LEt)4]2+ (X = Cl, Br), which can be isolated as their chloride or [PF6]? salts. The compounds are remarkably stable against air, moisture and ligand exchange. The hydroxo species [Re(NPh)(OH)(LEt)4]2+ is formed when moist solvents are used during the synthesis. The rhenium atoms in all three complexes are coordinated in a distorted octahedral fashion with the four NHC ligands in equatorial planes of the molecules. The Re–C(carbene) bond lengths between 2.171(8) and 2.221(3) Å indicate mainly σ‐bonding between the NHC ligand and the electron deficient d2 metal atoms. Attempts to prepare analogous phenylimido complexes from [Re(NPh)Cl3(PPh3)2] and 1,3‐diisopropyl‐4,5‐dimethylimidazole‐2‐ylidene (Li?Pr) led to a cleavage of the rhenium‐nitrogen multiple bond and the formation of the dioxo complex [ReO2(Li?Pr)4]+.  相似文献   

6.
Herein, we report the synthesis and characterization of a variety of novel poly(hydrogen halide) halogenates (−I). The bifluoride ion, which is known to have the highest hydrogen bond energy of ≈160 kJ mol−1, is the most famous among many examples of [X(HX)n] anions (X=F, Cl) known in the literature. In contrast, little is known about poly(hydrogen halide) halogenates containing two different halogens, ([X(HY)n]). In this work we present the synthesis of anions of the type [X(HY)n] (X=Br, I, ClO4; Y=Cl, Br, CN) stabilized by the [PPh4]+ and [PPN]+ cation. The obtained compounds have been characterized by single-crystal X-ray diffraction, Raman spectroscopy and quantum-chemical calculations. In addition, the behavior of halide ions in hydrogen fluoride was investigated by using experimental and quantum-chemical methods in order to gain knowledge on the acidity of hydrogen halides in HF.  相似文献   

7.
The reactions of [ReO(OEt)X2(PPh3)2] (X = Cl or Br) with 8-hydroxyquinoline (Hhqn) have been examined and the [ReOX(hqn)2] complexes have been obtained. The crystal and molecular structures of [ReOBr(hqn)2] have been determined. The electronic structure of [ReOBr(hqn)2] has been calculated with the density functional theory (DFT) method, and additional information about binding in the ReO3+ unit has been obtained by NBO analysis. The spin-allowed electronic transitions of [ReOBr(hqn)2] have been calculated with the time-dependent DFT method, and the UV–Vis spectra of the [ReOX(hqn)2] compounds have been discussed on this basis.  相似文献   

8.
Preparation and spectroscopic characterization of the decahalogenodirhenates(IV), [Re2X10]2?, X = Cl, Br On heating of [ReX6]2? with trifluoroacetic acid/trifluoroacetic anhydride (1 : 1), the edge-sharing bioctahedral anions [Re2X10]2?, X = Cl, Br are formed, which IR and Raman spectra are assigned according to point group D2h. The bands are found in three characteristic regions; at high wavenumbers stretching vibrations with terminal ligands v(ReClt): 367–321, v(ReBrt): 242–195; in an intermediate region with bridging ligands v(ReClb): 278–250, v(ReBrb): 201–167 cm?1, and at distinct lower frequencies the deformation modes. The absorption spectra of the dirhenates are distinguished in the region 600–1400 nm by eight intraconfigurational transitions with a slight bathochromic shift and higher intensities in comparison to the monomeric complexes. Due to a stronger bonding of the terminal ligands the energy of the charge transfer bands is lowered by about 4 000 cm?1, too. The magnetic moments are 3.32 and 3.81 B.M./ReIV for [Re2Cl10]2? and [Re2Br10]2?, respectively.  相似文献   

9.
Phosphonium Salts with Hydrogen Dihalide Anions HCl2?, HBr2?, HI2?, or HBrCl? Phosphonium hydrogen dihalides [R3PR′][XHY] (X = Y = Cl, Br, I; X = Br, Y = Cl) resp. [R3PH]HBr2 are obtained as extremely hydrolyzable crystals by reaction of phosphonium halides or tertiary phosphanes with hydrogen halide. According to IR spectroscopic results the solid compounds mostly contain anions [XHX]? with symmetric hydrogen bonds. In solution 1H NMR measurements show a slight (X = Cl, Br) or considerable (X = I) dissociation according to HX2? ? X? + HX. On heating the solid compounds decompose with formation of hydrogen halide and [R3PR′]X or [R3PH]X. In this process the hydrogen bromidechlorides [R3PR′][BrHCl] exclusively eliminate HCl. NMR studies (1H und 31P) with solutions containing [R3PH]HBr2 (R = phenyl, 1-naphtyl) or HBr and Ph3P in varying molar ratios show that a fast proton exchange between the competing Lewis bases R3P and Br? exists.  相似文献   

10.
Ruthenium(II) Phthalocyaninates(2–): Synthesis and Properties of (Acido)(carbonyl)phthalocyaninato(2–)ruthenate(II), [Ru(X)(CO)Pc2?]? (X = Cl, Br, I, NCO, NCS, N3) (nBu4N)[Ru(OH)2Pc2?] is reduced in acetone with carbonmonoxid to blue-violet [Ru(H2O)(CO)Pc2?], which yields in tetrahydrofurane with excess (nBu4N)X acido(carbonyl)phthalocyaninato(2–)ruthenate(II), [Ru(X)(CO)Pc2?]? (X = Cl, Br, I, NCO, NCS, N3) isolated as red-violet, diamagnetic (nBu4N) complex salt. The UV-Vis spectra are dominated by the typical π-π* transitions of the Pc2? ligand at approximately 15100 (B), 28300 (Q1) und 33500 cm?1 (Q2), only fairly dependent of the axial ligands. v(C? O) is observed at 1927 (X = I), 1930 (Cl, Br), 1936 (N3, NCO) 1948 cm?1 (NCS), v(C? N) at 2208 cm?1 (NCO), 2093 cm?1 (NCS) and v(N? N) at 2030 cm?1 only in the MIR spectrum. v(Ru? C) coincides in the FIR spectrum with a deformation vibration of the Pc ligand, but is detected in the resonance Raman(RR) spectrum at 516 (X = Cl), 512 (Br), 510 (N3), 504 (I), 499 (NCO), 498 cm?1 (NCS). v(Ru? X) is observed in the FIR spectrum at 257 (X = Cl), 191 (Br), 166 (I), 349 (N3), 336 (NCO) and 224 cm?1 (NCS). Only v(Ru? I) is RR-enhanced.  相似文献   

11.
Comparative analysis of the oxidizing and complexing properties of the DMSO–HX (X = Cl, Br, I) and DMSO–HX–ketone (X = Br, I; the ketone is acetone, acetylacetone, or acetophenone) systems toward silver was performed. The reaction products are AgX (X = Cl, Br, I), [Me3S+]Ag n X m (n= 1, 2; m= 2, 3; X = Br, I) and [Me2S+CH2COR]AgX 2(R = Me, Ph; X = Br, I). The composition of the obtained complexes depends on both the DMSO : HX ratio and the nature of HX, as well as on the methods used to isolate solid products from the solution. It was noted that the formation of the [Me2S+CH2COMe]AgBr 2complex in the Ag0–DMSO–HBr–acetylacetone system occurs with cleavage of the acetylacetone C–C bond and follows a specific reaction course. The optimum conditions for production of the silver compounds in the title systems are determined.  相似文献   

12.
The reactions of [ReOX3(AsPh3)2] (X = Cl, Br) with 4,7-diphenyl-1,10-phenanthroline (dpphen) have been examined and the complexes [ReO(OMe)X2(dpphen)] and [Re2O3X4(dpphen)2]·2/3CH2Cl2 (X = Cl, Br) have been obtained. They were characterized by IR, UV–Vis spectroscopy, and single crystal X-ray analysis has been performed for [ReO(OMe)Cl2(dpphen)] and [Re2O3Br4(dpphen)2]·2/3CH2Cl2. The nature of the frontier orbitals of [ReO(OMe)Cl2(dpphen)] and [Re2O3Br4(dpphen)2] and the electronic transitions involved in the absorption spectra have been studied by means of the density functional and time-dependent density functional methods.  相似文献   

13.
Reactions of the oxorhenium(V) complexes [ReOX3(PPh3)2] (X = Cl, Br) with the N‐heterocyclic carbene (NHC) 1,3,4‐triphenyl‐1,2,4‐triazol‐5‐ylidene (LPh) under mild conditions and in the presence of MeOH or water give [ReOX2(Y)(PPh3)(LPh)] complexes (X = Cl, Br; Y = OMe, OH). Attempted reactions of the carbene precursor 5‐methoxy‐1,3,4‐triphenyl‐4,5‐dihydro‐1H‐1,2,4‐triazole ( 1 ) with [ReOCl3(PPh3)2] or [NBu4][ReOCl4] in boiling xylene resulted in protonation of the intermediately formed carbene and decomposition products such as [HLPh][ReOCl4(OPPh3)], [HLPh][ReOCl4(OH2)] or [HLPh][ReO4] were isolated. The neutral [ReOX2(Y)(PPh3)(HLPh)] complexes are purple, airstable solids. The bulky NHC ligands coordinate monodentate and in cis‐position to PPh3. The relatively long Re–C bond lengths of approximate 2.1Å indicate metal‐carbon single bonds.  相似文献   

14.
Zusammenfassung Die chemischen Effekte des isomeren Überganges von80mBr wurden bei Temperaturen von–78° C und–196° C an mit80mBr markierten Proben von [Co(NH3)5 X]Br3.2 nH2O und [Co(en)2 X 2']Br3.1 nH2O untersucht (X=NH3, NCS, NO2, OH2, ONO, ONO2, F, Cl, Br, I, undX'=en, NH3, NCS, Cl, Br). Es zeigte sich, daß die Ligandenausbeute an80Br, in den Komplexen mit abnehmender Frequenz des Maximums in der ersten Absorptionsbande des [Co(NH3)5 X] und des [Co(en)2 X 2'] zunimmt. Mit anderen Worten, weniger stabile, Liganden werden leichter von Radiobrom ersetzt als Folge des isomeren Überganges in festen Komplexen.
Chemical effects of the isomeric transition of80mBr in pentammincobalt(III) and bisethylenediaminecobalt(III) bromides
The chemical effects of the isomeric transition of80mBr were investigated at temperatures of–78° C and–196° C with80mBr-labeled samples of [Co(NH3)5 X]Br3.2 nH2O and [Co(en)2 X 2']Br3.1 nH2O (X=NH3, NCS, NO2, OH2, ONO, ONO2, F, Cl, Br, I, andX'=en, NH3, NCS, Cl, Br). The ligand yield of80Br in the complexes was found to increase with the decrease in the frequency of the maximum in the first absorption band of [Co(NH3)5 X] and [Co(en)2 X 2']. In other words, less stable ligands were more easily replaced by radiobromine as a consequence of isomeric transition in solid complexes.


Mit 1 Abbildung

Herrn Prof. Dr.E. Broda zum 60. Geburtstag gewidmet.  相似文献   

15.
Heteronuclear Metal Atom Clusters of the Types X4?n[SnM(CO)4P(C6H5)3]n and M2(CO)8[μ-Sn(X)M(CO)4P(C6H5)3]2 by Reaction of SnX2 with M2(CO)8[P(C6H5)3]2 (X = Halogene; M = Mn, Re; n = 2, 3) The compounds of the both types X4?n[SnM(CO)4P(C6H5)3]n (n = 3; M = Mn; X = F, Cl, Br, I. n = 2: M = Mn, Re; X = Cl, Br, I) and M2(CO)8[μ-Sn(X)M(CO)4P(C6H5)3]2 (M = Mn; X = Cl, I. M = Re; X = Cl, Br, I) are prepared by reaction of SnX2 with M2(CO)8[P(C6H5)3]2 (M = Mn, Re). Their IR frequencies are assigned. In Re2(CO)8[μ-Sn(Cl)Re(CO)4P(C6H5)3]2 the central molecule fragment contains a planar Re2Sn2 rhombus with a transannular Re? Re bond of 316.0(2) pm. Each of the SnIV atoms is connected with the terminal ligands Cl and Re(CO)4P(C6H5)3. These ligands are in transposition with respect to the Re2Sn2 ring. The mean values for the remaining bond distances (pm) are: Sn? Re = 274.0(3); Sn? Cl = 243(1), Re? C = 176(5), Re? P = 242.4(9), C? O = 123(5). The factors with an influence on the geometrical shape of such M2Sn2 rings (M = transition metal) are discussed.  相似文献   

16.
By a reaction of [BiX6]3– with salts of various N-alkylated pyridine derivatives in 2M HX (X = Cl, Br), (N-BzPy)4[Bi2X10] complexes (X = Cl (1), Br (2), (4-MePyH)4[Bi2Cl10] (3)) are obtained and structurally characterized.  相似文献   

17.
Reactions of [Re(NPh)Cl3(PPh3)2] with N‐[(N′,N′‐dialkylamino)(thiocarbonyl)]benzamidines (H2R2tcb) (R2 = Et2, (CH2)2O(CH2)2) in methanol give mono‐chelates of the composition [Re(NPh)Cl2(PPh3)(HR2tcb)] as the sole products independent of the amount of the added H2R2tcb. Addition of a supporting base such as NEt3 results in hydrolysis of the Re=NPh bonds and partial hydrolysis of the thiocarbamoylbenzamidines. Orange‐brown, cationic oxorhenium(V) compounds of the formula [ReO(HR2tcb)2]Cl were isolated from such reaction mixtures in good yields, and the formation of small amount of the unusual sulfido/persulfido‐bridged ReV dimer [{ReO(HEt2tcb)}2(μ‐S)(μ‐S2)] give evidence for a considerable degree of ligand decomposition under such conditions. The products have been characterized by spectroscopic methods and X‐ray crystallography. Acidification of orange‐brown solutions of the five‐coordinate ReV oxo complex [ReO(HEt2tcb)2]Cl causes an immediate change of the color and deep blue crystals of the neutral, six‐coordinate [ReOCl(HEt2tcb)2] can be isolated from the resulting mixture. Alternatively, the product can be prepared by a ligand‐exchange protocol starting from (NBu4)[ReOCl4] and H2Et2tcb. The pH‐dependent isomerization between [ReO(HEt2tcb)2]Cl and [ReOCl(HEt2tcb)2] is reversible.  相似文献   

18.
The complex salt [ReO(bsa)]PF6 (H2bsa?=?bis(N-methylsalicylideneiminopropyl)amine) was prepared from the reaction of cis-[ReO2I(PPh3)2] with H2bsa in toluene. The dianionic pentadentate ligand bsa is coordinated to the ReO3+ moiety via one secondary amino and two imino nitrogens, and two anionic phenolate oxygens. The complex was characterized by spectroscopy and analytical data, and the structure has been determined by single-crystal X-ray diffraction analysis.  相似文献   

19.
A new bis(pyrazolylpyridine) ligand (H2L) has been prepared to form functional [Fe2(H2L)3]4+ metallohelicates. Changes to the synthesis yield six derivatives, X@[Fe2(H2L)3]X(PF6)2?xCH3OH ( 1 , x=5.7 and X=Cl; 2 , x=4 and X=Br), X@[Fe2(H2L)3]X(PF6)2?yCH3OH?H2O ( 1 a , y=3 and X=Cl; 2 a , y=1 and X=Br) and X@[Fe2(H2L)3](I3)2?3 Et2O ( 1 b , X=Cl; 2 b , X=Br). Their structure and functional properties are described in detail by single‐crystal X‐ray diffraction experiments at several temperatures. Helicates 1 a and 2 a are obtained from 1 and 2 , respectively, by a single‐crystal‐to‐single‐crystal mechanism. The three possible magnetic states, [LS–LS], [LS–HS], and [HS–HS] can be accessed over large temperature ranges as a result of the structural nonequivalence of the FeII centers. The nature of the guest (Cl? vs. Br?) shifts the spin crossover (SCO) temperature by roughly 40 K. Also, metastable [LS–HS] or [HS–HS] states are generated through irradiation. All helicates (X@[Fe2(H2L)3])3+ persist in solution.  相似文献   

20.
Summary 2,6-Dimethyl-4H-pyran-4-thione (DMTP) acts as a sulphur donor towards PtII and PdII halides yielding adducts of general formula [M(DMTP)2X2] (M=Pd or Pt; X=Cl, Br or I). When complex syntheses are performed in benzene, the solvated species [M(DMTP)2X2]·C6H6 (M=Pd or Pt; X=Cl or Br) are obtained. The compounds have been characterized by i.r. and n.m.r. (1H and13C) spectroscopy and by thermogravimetric data. The adduct geometry and the influence of benzene are discussed.  相似文献   

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