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1.
Reaction of CsF with ClF3 leads to Cs[Cl3F10]. It contains a molecular, propeller‐shaped [Cl3F10]? anion with a central μ3‐F atom and three T‐shaped ClF3 molecules coordinated to it. This anion represents the first example of a heteropolyhalide anion of higher ClF3 content than [ClF4]? and is the first Cl‐containing interhalogen species with a μ‐bridging F atom. The chemical bonds to the central μ3‐F atom are highly ionic and quite weak as the bond lengths within the coordinating XF3 units (X = Cl, and also calculated for Br, I) are almost unchanged in comparison to free XF3 molecules. Cs[Cl3F10] crystallizes in a very rarely observed A[5]B[5] structure type, where cations and anions are each pseudohexagonally close packed, and reside, each with coordination number five, in the trigonal bipyramidal voids of the other.  相似文献   

2.
The interaction of bisperhalophenyl aurates [AuR2]? (R?=?C6F5, C6F3Cl2, and C6Cl5) with the closed-shell Ag+, Cu+, and Tl+ ions has been studied theoretically and compared with the experimentally known X-ray diffraction crystal structures. Initially, the aurates have been fully optimized at MP2 level of theory in a D 2h symmetry. The analysis of the basicity of the three aurates [AuR2]? (R?=?C6F5, C6F3Cl2 and C6Cl5) against Ag+ ions in a C 2v symmetry has been calculated in point-by-point bsse-corrected interaction energy analysis at HF and MP2 levels of theory. Taking into account the experimental observation of additional interactions between the heterometals and C ipso atoms at the perhalophenyl rings or halogen atoms at the ortho position of the perhalophenyl rings, dinuclear models of the type [AuR2]?···Ag+ (R?=?C6Cl5, and C6F5); [AuR2]?···Cu+ (R?=?C6F5, and C6Cl5) and [AuR2]?···Tl+ (R?=?C6F5, and C6Cl5) with a C 2v , C 2 , and C s symmetries have been optimized at DFT-B3LYP level. The interaction energies have been computed through bsse-corrected single point HF and MP2 calculations. The energy stabilization provided and the heterometal preference have been analyzed and compared with the experimental results.  相似文献   

3.
The Crystal Structure of the 1:1 Addition Compound between Antimony Trichloride and Diphenylammonium Chloride, SbCl3 · (C6H5)2NH2+Cl? The 1:1 addition compound between antimony trichloride and diphenylammoniumchloride SbCl3 · (C6H5)2NH2+Cl? crystallizes in the monoclinic space group P21/n with a = 5.668(8), b = 20.480(12), c = 14.448(17) Å, β = 110.4(1)° and Z = 4 formula units. Chains of SbCl3 molecules and anion cation chains are bridged by Cl ions and form square tubes. The coordination of the Sb atoms by Cl atoms by Cl atoms and Cl ions is distorted octahedral. Mean distances are Sb? Cl = 2.37 Å for Sb? Cl (3×), 3.09 Å for Sb…Cl? (2×) and 3.42 Å for Sb…Cl (1×). The Sb…Cl? contacts and hydrogen bonds NH…Cl? at 3.15 Å generate tetrahedral coordination of the Cl ions.  相似文献   

4.
The products of the reaction between the electrophilic alkenylxenonium cation [1-Xe+–C6F9] and the halide anions I?, Br?, Cl? and F? depend on the hardness of the halide anion. With the soft halides I? and Br? Xe(II) is formally displaced by halogen as well in basic MeCN as in superacidic (AHF1), whereas with hard fluoride and chloride no reaction takes place in AHF. In MeCN F? initiates the formation of alkenyl radicals, which abstract hydrogen from the solvent, whereas Cl? exhibits borderline character: RH and RCl formation. Possible reaction paths are discussed. The reactivity of the arylxenonium cation [C6F5Xe]+ in AHF toward halide ions is reported and the relative electrophilicity of the cations [C6F5Xe]+ and [1-Xe+–C6F9] is determined by the competitive reaction with Cl?. In addition the synthesis of cyclohexene 1-CF3–C6F9 from C6F5CF3 and XeF2 is performed and its electrophilicity is compared with that of the aromatic compound C6F5CF3.  相似文献   

5.
The reactivity of the C6F5X (X=F, Cl, Br, I) molecules following low energy (0–15 eV) electron attachment is studied in the gas phase under single collision conditions, free molecular clusters and condensed molecules by means of crossed beams and surface experiments. All four molecules exhibit a very prominent resonance for low energy electron attachment (<1 eV, attachment cross section >10−14 cm2). Under collision free conditions thermal electron capture generates long lived molecular parent anions C6F5X−*. Along the line Cl, Br, I dissociation into X+C6F5 and X+C6F5-increasingly competes until for X=1 only chemical fragmentation is observed on the mass spectrometric time scale. In free molecular clusters chemical fragmentation is quantitatively quenched at low energies in favour of associative attachment yielding undissociated, relaxed ions (C6F5X) n,n≥1. A further dissociative resonance at 6.5 eV in C6F5Cl is considerably enhanched in clusters. If these molecules are finally condensed on a solid surface, one observes a prominent Cl desorption resonance at 6.5 eV. While the quantitative quenching of the chemical reactivity at low energies is due to the additional possibilities of energy dissipation under aggregation, the enhanched reactivity at 6.5 eV is interpreted by the conversion of a core excited open channel resonance in single molecules into a closed channel (Feshbach) resonance when it is coupled to environmental molecules.  相似文献   

6.
In the crystal structure of the title compound, [LiPd2Cl4(C12H12N2)2](C24F20B)·1.196CD2Cl2 or [{(Me2bipy)PdCl2}2(μ‐Li)]+·B(C6F5)4·1.196CD2Cl2 (Me2bipy is 4,4′‐di­methyl‐2,2′‐bi­pyridine), an Li+ cation is stabilized by complexation with two (Me2bipy)PdCl2 units through weak Li—Cl interactions. This compound is thus a rare example of a complex that exhibits an arrested Cl abstraction.  相似文献   

7.
A reaction between C6F5Cl and elemental fluorine under pressure produced pentafluorophenylchlorine(III)difluoride(1) and 1,2-difluoro-1,2-bis(pentafluorophenyl)dichlorane, C6F5Cl(F)Cl(F)C6F5.The dichlorane was a stable colorless liquid with a boiling point of 121 – 123°. Its characterization by elemental analysis, IR, NMR and Mass Spectra will be presented. It is believed to be the first stable compound with a chlorine-chlorine bond and may be considered to be a derivative of the unknown Cl2F4.  相似文献   

8.
We studied the time‐of‐flight secondary ion mass spectrometry fragmentation mechanisms of polystyrenes—phenyl‐fluorinated polystyrene (5FPS), phenyl‐deuterated polystyrene (5DPS), and hydrogenated polystyrene (PS). From the positive ion spectra of 5FPS, we identified some characteristic molecular ion structures with isomeric geometries such as benzylic, benzocyclobutene, benzocyclopentene, cyclopentane, and tropylium systems. These structures were evaluated by the B3LYP‐D/jun‐cc‐pVDZ computation method. The intensities of the C7H2F5+ (m/z = 181), CyPent‐C9H3F4+ (m/z = 187), CyPent‐C9H4F5+ (m/z = 207), and CyPent‐C9H2F5+ (m/z = 205) ions were enhanced by resonance stabilization. The positive fluorinated ions from 5FPS tended to rearrange and produce fewer fluorine‐containing molecular ions through the loss of F (m/z = 19), CF (m/z = 31), and CF2 (m/z = 50) ion fragments. Consequently, the fluorine‐containing polycyclic aromatic ions had much lower intensities than their hydrocarbon counterparts. We propose the fragmentation mechanisms for the formation of C5H5+, C6H5+, and C7H7+ ion fragments, substantiated with detailed analyses of the negative ion spectra. These ions were created through elimination of a pentafluoro‐phenyl anion (C6F5) and H+, followed by a 1‐electron‐transfer process and then cyclization of the newly generated polyene with carbon‐carbon bond formation. The pendant groups with elements of different electronegativities exerted strong influences on the intensities and fragmentation processes of their corresponding ions.  相似文献   

9.
Metal Complexes of Biologically Important Ligands. XCV. η5-Pentamethylcyclopentadienyl Rhodium, Iridium, η6- Benzene Ruthenium, and Phosphine Palladium Complexes of Proline Methylester and Proline Amide Proline methylester (L1) and proline amide (L2) give with the chloro bridged complexes [(η5 -C5Me5)MCl2]2 (M ? Rh, Ir), [(η6 -benzene)RuCl2]2 and [Et3PPdCl2]2 N and N,O coordinated compounds: (η5 -C5Me5)M(Cl2)L1 ( 1, 2 M ? Rh, Ir), [(η5-C5Me5) Rh(Cl)(L2)]+Cl? ( 5 ), [(η6- C6Me6) Ru(Cl)(L2)]+Cl? ( 6 ), [(η6-p-cymene)Ru(Cl)(L2)]+Cl? ( 7 ), [(eta;5-C5Me5)M(Cl)(L2-H+)] ( 9, 10 M ? Rh, Ir), (Et3P)Pd(Cl)2L1 ( 3 ), and [(Et3P)Pd(Cl)(L2)]+Cl? ( 8 ). The NMR spectra indicate that for 5 and 6 only one diastereoisomer is formed. The complexes 1, 2, 3 and 5 were characterized by X-ray diffraction.  相似文献   

10.
The reaction mechanism of F2+Cl2→2ClF has been investigated with the density functional theory at the B3LYP/6‐311G* level. Six transition states have been found for the three possible reaction paths and verified by the normal mode vibrational and IRC analyses. Ab initio MP2/6‐311G* geometry optimizations and CCSD(T)/6‐311G(2df)//MP2/6‐311G* single‐point energy calculations have been performed for comparison. It is found that when the F2 (or Cl2) molecule decomposes into atoms first and then the F (or Cl) atom reacts with the molecule Cl2 (or F2) nearly along the molecular axis, the energy barrier is very low. The calculated energy barrier of F attacking Cl2 is zero and that of Cl attacking F2 is only 15.57 kJ?mol?1 at the B3LYP level. However, the calculated dissociation energies of F2 and Cl2 are as high as 145.40 and 192.48 kJ?mol?1, respectively. When the reaction proceeds through a bimolecular reaction mechanism, two four‐center transition states are obtained and the lower energy barrier is 218.69 kJ?mol?1. Therefore, the title reaction F2+Cl2→2ClF is most probably initiated from the atomization of the F2 molecule and terminated by the reaction of F attacking Cl2 nearly along the Cl? Cl bond. MP2 calculations lead to the same conclusion, but the geometry of TS and the energy barrier are somewhat different. © 2002 John Wiley & Sons, Inc. Int J Quantum Chem, 2002  相似文献   

11.
A range of frustrated Lewis pairs (FLPs) containing borenium cations have been synthesised. The catechol (Cat)‐ligated borenium cation [CatB(PtBu3)]+ has a lower hydride‐ion affinity (HIA) than B(C6F5)3. This resulted in H2 activation being energetically unfavourable in a FLP with the strong base PtBu3. However, ligand disproportionation of CatBH(PtBu3) at 100 °C enabled trapping of H2 activation products. DFT calculations at the M06‐2X/6‐311G(d,p)/PCM (CH2Cl2) level revealed that replacing catechol with chlorides significantly increases the chloride‐ion affinity (CIA) and HIA. Dichloro–borenium cations, [Cl2B(amine)]+, were calculated to have considerably greater HIA than B(C6F5)3. Control reactions confirmed that the HIA calculations can be used to successfully predict hydride‐transfer reactivity between borenium cations and neutral boranes. The borenium cations [Y(Cl)B(2,6‐lutidine)]+ (Y=Cl or Ph) form FLPs with P(mesityl)3 that undergo slow deprotonation of an ortho‐methyl of lutidine at 20 °C to form the four‐membered boracycles [(CH2{NC5H3Me})B(Cl)Y] and [HPMes3]+. When equimolar [Y(Cl)B(2,6‐lutidine)]+/P(mesityl)3 was heated under H2 (4 atm), heterolytic cleavage of dihydrogen was competitive with boracycle formation.  相似文献   

12.
Ionic fragmentations induced by electron-impact on compounds of the type C6F5SX (X ? H, CH3, COCH3, Cl, C6F5) and (C6F5S)2, (C6F5S)2Hg, (C6F5S)3As and (C6F5SCH2)2 have been studied. Principal features of the mass spectra are reported. The [C6F5S]+ ion (m/e 199) is predominant and its mode of fragmentation has been deduced. The precursor ions for m/e 199 have been examined in (C6F5)2S, (C6F5S)2, (C6F5S)2Hg, (C6F5S)3As and C6F5SCl. Ion kinetic energy spectra of (C6F5)2S, (C6F5S)2, (C6F5S)2Hg and C6F5SCl have been recorded, and all contain peaks corresponding to the fragmentation of the [C6F5S]+ ion.  相似文献   

13.
Dihalogen(Pentafluorophenyl)sulfonium(IV) Hexafluoroarsenate C6F5SX2+AsF6? (X = Cl, Br) and Crystal Structure of Di(pentafluorophenyl)sulfane (C6F5)2S The preparation and spectroscopic characterisation of the halogensulfonium salts C6F5SCl2+AsF6? and C6F5SBr2+AsF6? is reported. The new salts are much more stable than their trifluoromethyl derivatives. In addition the crystal structure of (C6F5)2S is reported. Space group P43212, Z = 4, 478 unique observed diffractometer data, Rint. = 0.07, lattice constants: a = 569.0(5) pm, c = 3785.8(22) pm, V = 1225 times; 10?30 m3.  相似文献   

14.
Summary By means of cryogenic sampling and subsequent gas-chromatographic analysis vertical profiles of CCl4, CCl3F, CCl2F2, CClF3, CF4, C2Cl3F3, C2Cl2F4, C2ClF5, C2F6, CH3Cl and CH3CCl3 were derived for stratospheric heights up to 35 km. Vertical profiles of halocarbons computed by means of one-dimensional and two-dimensional models fall off less rapidly in the stratosphere than the measured profiles, this systematic discrepancy being due to deficiencies in the radiation and transport schemes of present models. It is shown that measured profiles of fully halogenated hydrocarbons provide a tool for systematically studying these deficiencies and thus improving the models. Sources and sinks of halocarbons are discussed, and an assessment of past and future sources of organically bound chlorine in the atmosphere is made.
Die vertikale Verteilung halogenierter Kohlenwasserstoffe in der stratosphäre
Zusammenfassung Die vertikalen Profile von CCl4, CCl3F, CCl2F2, CClF3, CF4, C2Cl3F3, C2Cl2F4, C2ClF5, C2F6, CH3Cl und CH3CCl3 wurden für stratosphärische Höhen bis zu 35 km mit Hilfe kryogener Probenahme und anschließender gas-chromatographischer Analyse bestimmt. Die mit Hilfe von ein- und zweidimensionalen Modellen berechneten Profile fallen in der Stratosphäre weniger schnell ab als die gemessenen. Dieser systematische Unterschied ist auf Mängel in den Strahlungs- und Transportmechanismen der gegenwärtigen Modelle zurückzuführen. Es wird gezeigt, daß die gemessenen Profile der vollhalogenisierten Kohlenwasserstoffe dazu dienen können, diese Mängel zu untersuchen und die Modelle zu verbessern. Ursprung und Verbleib der halogenierten Kohlenwasserstoffe werden beschrieben und vergangene und zukünftige Quellen organisch gebundenen Chlors in der Atmosphäre diskutiert.
  相似文献   

15.
The pnictocenium salts [Cp*PCl]+[μCl]? ( 1 a ), [Cp*PCl]+[ClAl(ORF)3]? ( 1 b ), [Cp*AsCl]+[ClAl(ORF)3]? ( 2 ), and [(Cp*)2P]+[μCl]? ( 3 ), in which Cp*=Me5C5, μCl=(FRO)3Al? Cl? Al(ORF)3, and ORF=OC(CF3)3, were prepared by halide abstraction from the respective halopnictines with the Lewis superacid PhF→Al(ORF)3. 1 The X‐ray crystal structures of 1 a , 2 , and 3 established that in the half as well as in the sandwich cations the Cp* rings are attached in an η2‐fashion. By using one or two equivalents of the Lewis acid, the two new weakly coordinating anions [μCl]? and [ClAl(ORF)3]? resulted. They also stabilize the highly reactive cations in PhF or 1,2‐F2C6H4 solution at room temperature. The chloride ion affinities (CIAs) of a range of classical strong Lewis acids were also investigated. The calculations are based on a set of isodesmic BP86/SV(P) reactions and a non‐isodesmic reference reaction assessed at the G3MP2 level.  相似文献   

16.
The β modification of pyridinium di­chloro­iodide, C5H6N+·Cl2I?, was obtained as yellow crystals by the reaction of (C5NH5)AuCl3, C5H6N+·Cl? and I2 in a vacuum‐sealed ampoule. The di­chloro­iodide ion is nearly symmetric and linear with I—Cl bond lengths of 2.544 (3) and 2.550 (3) Å and a Cl—I—Cl angle of 179.68 (12)°.  相似文献   

17.
Reaction of [Au(C6F5)(tht)2Cl](OTf) with RaaiR′ in CH2Cl2 medium leads to [Au(C6F5)(RaaiR′)Cl](OTf) [RaaiR′ = p-R–C6H4–N=N–C3H2–NN-1-R′, (1–3), abbreviated as N,N′-chelator, where N(imidazole) and N(azo) represent N and N′, respectively; R = H (a), Me (b), Cl (c) and R′ = Me (1), CH2CH3 (2), CH2Ph (3), tht is tetrahydrothiophen]. The maximum molecular peak of [Au(C6F5)(MeaaiMe)Cl] is observed at m/z 599.51 (100 %) in the FAB mass spectrum. Ir spectra of the complexes show –C=N– and –N=N– stretching near at 1590 and 1370 cm−1 and near at 1510, 955, 800 cm−1 due to the presence of pentafluorophenyl ring. The 1H-NMR spectral measurements suggest methylene, –CH2–, in RaaiEt gives a complex AB type multiplet while in RaaiCH2Ph shows AB type quartets. 13C-NMR spectrum of complexes confirm the molecular skeleton. In the 1H-1H-COSY spectrum as well as contour peaks in the 1H-13C HMQC spectrum for the present complexes, assign the solution structure and stereoretentive conformation. The electrochemistry gives the ligand reduction peaks.  相似文献   

18.
A photochemical route to salts consisting of difluorooxychloronium(V) cations, [ClOF2]+, and hexafluorido(non)metallate(V) anions, [MF6] (M=V, Nb, Ta, Ru, Os, Ir, P, Sb) is presented. As starting materials, either metals, oxygen and ClF3 or oxides and ClF3 are used. The prepared compounds were characterized by single-crystal X-ray diffraction and Raman spectroscopy. The crystal structures of [ClOF2][MF6] (M=V, Ru, Os, Ir, P, Sb) are layer structures that are isotypic with the previously reported compound [ClOF2][AsF6], whereas for M=Nb and Ta, similar crystal structures with a different stacking variant of the layers are observed. Additionally, partial or full O/F disorder within the [ClOF2]+ cations of the Nb and Ta compounds occurs. In all compounds reported here, a trigonal pyramidal [ClOF2]+ cation with three additional Cl⋅⋅⋅F contacts to neighboring [MF6] anions is observed, resulting in a pseudo-octahedral coordination sphere around the Cl atom. The Cl−F and Cl−O bond lengths of the [ClOF2]+ cations seem to correlate with the effective ionic radii of the MV ions. Quantum-chemical, solid-state calculations well reproduce the experimental Raman spectra and show, as do quantum-chemical gas phase calculations, that the secondary Cl⋅⋅⋅F interactions are ionic in nature. However, both solid-state and gas-phase quantum-chemical calculations fail to reproduce the increases in the Cl−O bond lengths with increasing effective ionic radius of M in [MF6] and the Cl−O Raman shifts also do not generally follow this trend.  相似文献   

19.
Pentafluorophenyliodine(III) Compounds. 2. Fluorine-Aryl Substitution Reactions on Iodinetrifluoride: Synthesis of Pentafluorophenyliodinedifluoride C6F5IF2 and Bis(pentafluorophenyl)iodonium Pentafluorophenylfluoroborates[(C6F5)2I]+[(C6F5)nBF4?n]? Mono- and disubstitution can be achieved in the fluorine-aryl substitution reaction on the low-temperature phase IF3 in CH2Cl2 at ?78°C depending on the aryl transfer reagent. With B(C6F5)3 [(C6F5)2I]+ [(C6F5)nBF4?n]? (68% yield) and with Cd(C6F5)2 C6F5IF2 (97% yield) is obtained whereas with C6F5SiMe3 no fluorine-aryl substitution takes place on IF3 even under basic conditions (EtCN or F? addition). At ?78°C in EtCN solution IF3 does not disproportionate but attacks the solvent under formation of HF.  相似文献   

20.
From suitable perhalophenyl derivatives of palladium(II), viz.: Pd(C6F5)2-(SC4H8)2, [Pd(μ-X′) (C6X5)2]2(NBu4)2, [Pd(μ-Cl)(C6X5)(SC4H8)]2 (X = F, Cl, X′ = Cl, Br), new complexes of various types have been prepared, viz.: trans-Pd(C6F5)2(Y)2, Pd(C6X5)2(Y), PdCl(C6X5)(Y) (X = F, Cl). The neutral ligand Y is a keto-stabilized phosphorus ylide of the type Ph2P(CH2)nPPh2CHC(O)R (n = 1, R = CH3, C6H5; n = 2, R = C6H5) acting in a terminal monodentate P-donor or a bidentate chelate P,C-donor mode. The reaction of PdCl(C6F5)(Y) complexes with HCl leads to the corresponding PdCl2(C6F5)(YH) complexes in which the phosphonium cation [YH]+ behaves as monodentate P-donor at its phosphinic end.IR and 31P NMR spectroscopy were used to decide the coordination mode of the ligands and, in some cases, to reveal the presence of two isomers.  相似文献   

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