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1.
103Rh NMR Spectroscopic Evidence of Mixed Nonahalogenodirhodates(III), [Rh2ClnBr9–n]3?, n = 0–9 On heating a mixture of the tetrabutylammonium salts (TBA)3[Rh2Cl9] and (TBA)3[Rh2Br9] at 60°C in propylenecarbonate the complete system of the mixed nonahalogenodirhodates(III) [Rh2ClnBr9–n]3?, n = 0–9 is formed. In the 103Rh nmr spectra 40 different species have been detected, 16 with two equivalent 103Rh atoms each resulting in one singlet and 24 with inequivalent 103Rh atoms each pair giving two resonances. The signals of the geometric isomeres are not resolved. All 64 expected resonances are really observed. By additional measuring of the 103Rh nmr spectra of the fractions n = 0–4 separable by ion exchange chromatography on DEAE cellulose, and utilizing characteristic increments of chemical shifts the complete and unambiguous assignment of all signals is achieved.  相似文献   

2.
A well applicable preparative method for lithium perfluoroalkyltrimethoxyborates, Li[CnF2n+1B(OMe)3] (n = 3, 4, 6), was elaborated which is based on the reaction of B(OMe)3 with CnF2n+1Li generated from CnF2n+1H and t‐BuLi. Alternative perfluoroalkylation reactions of B(OMe)3 with perfluoropropyllithium generated from C3F7I and RLi, perfluoropropylmagnesium bromide, or perfluoropropyltrimethylsilane and potassium fluoride gave less satisfactory results for M[C3F7B(OMe)3]. The conversion of M[CnF2n+1B(OMe)3] salts (M = Li, BrMg) into K[CnF2n+1B(OMe)3] salts and basic properties of the new salts are reported.  相似文献   

3.
Metal Complexes with Anionic Ligands of Elements of the Main Group IV. IV. Homogenous and Heterogenous Transition Metal Complexes of the Dichlorobromo-, Dibromochloro-, and Tribromostannide Ligands Monosubstituted complexes of the type [M(CO)5SnBr3?nCln]? are formed if the hexacarbonyls of chromium, molybdenum, and tungsten are reacted with halogenostannide ions SnBr3?nCl (n = 0, 1, 2). The reactions of dibenzene chromium and this stannide ions yield homogenous hexakis(trihalogenostannide)chromate(0) complexes [Cr(SnBr3?nCln)6]6? (n = 1, 2). Both types of chromate(0) ions are isolated as salts with the cation [N(C2H5)4]+. The behaviour of SnBr3?nCl (n = 0–3) as ligands is discussed, the i. r. spectra of their metalcarbonyl derivatives are reported.  相似文献   

4.
On the Reaction of Halomethylphosphonium Halides, [R3PCYnX3–n]X, with Phosphanes, R′3P The results of the reaction of 19 different halomethylphosphonium halides, [R3PCYnX3–n]X (R = Ph, n-Bu, Me2N, Et2N; Y = H, F; X = Cl, Br, I; n = 0–2), with Ph3P, n-Bu3P, and (R2N)3P are presented. As reaction products bisphosphonium salts, [R3P? CYnX2–n? PR′3]X2, and phosphoranylphosphonium salts, [R3P=CY? PR′3]X, or reduced (halo)methyl-phosphonium salts, [R3PCHYnX2–n]X, are obtained. [Ph3PCBrF2]Br and [Bu3PCBrF2]Br react with R′3P by trans-alkylation forming [R′3PCBrF2]Br. The factors influencing the course of the reaction are discussed.  相似文献   

5.
Preparation and Vibrational Spectra of Nonahalogenodirhodates(III), [Rh2ClnBr9-n]3?, n = 0–9 The pure nonahalogenodirhodates(III), A3[Rh2ClnBr9-n], A = K, Cs, (TBA); n = 0–4, 9, have been prepared. They are formed from the monomer chlorobromorhodates(III), [RhClnBr6-n]3?, n = 0–6, which are bridged to confacial bioctahedral complexes by ligand abstraction in less polar organic solvents. From the mixtures the complexions are separated by ion exchange chromatography on DEAE-cellulose. The solid, air-stable, air-stable, K-, Cs- and (TBA)-salts of [Rh2ClnBr9-n]3?, n = 0–4, are green, of [Rh2Cl9]3? are brown. The IR and Raman spectra of [Rh2Br9]3? and [Rh2Cl9]3? are assigned according to the point group D3h. The chlorobromodirhodates exist as mixtures of geometrical and structural isomers, which belong to different point groups. The vibrational spectra exhibit bands in characteristic regions; at high wavenumbers stretching vibrations with terminal ligands v(Rh—Clt): 360–320, v(Rh—Brt): 280–250; in a middle region with bridging ligands v(Rh—Clb): 300–270, v(Rh—Brb): 210–170 cm?1; the deformation bands are observed at distinct lower frequencies. The terminal ligands are fixed very strong, and the distance between v(Rh—Xt) and v(Rh—Xb) increases with decreasing size of the cations.  相似文献   

6.
The charge exchange and charge separation processes of a series of [C3Hn]2+ and [C3Dn]2+ (n = 1–6) dications have been investigated experimentally in a mass spectrometer of reversed geometry. The relative reaction cross-sections for charge exchange with nitrogen exhibited a 20-fold variation which has implications for the interpretation of 2E spectra with respect to dication relative intensities. Charge separation resulting in deprotonation was observed for all [C3Dn]2+ species investigated, while de-deuteronation was observed for [C3Dn]2+ (n = 1–4) only. Intercharge separations calculated from the observed ion kinetic energies released upon charge separation suggest linear structures for [C3Dn]2+ and [C3Dn]2+ (n = 1–2) and cyclic structures for [C3Dn]2+ (n = 3–6) and [C3Dn]2+ (n = 3–4).  相似文献   

7.
Synthesis, Crystal Structures, and Vibrational Spectra of [Pt(N3)6]2– and [Pt(N3)Cl5]2–, 195Pt and 15N NMR Spectra of [Pt(N3)nCl6–n]2– and [Pt(15NN2)n(N215N)6–n]2–, n = 0–6 By ligand exchange of [PtCl6]2– with sodium azide mixed complexes of the series [Pt(N3)nCl6–n]2– and with 15N‐labelled sodium azide (Na15NN2) mixtures of the isotopomeres [Pt(15NN2)n(N215N)6–n]2–, n = 0–6 and the pair [Pt(15NN2)Cl5]2–/[Pt(N215N)Cl5]2– are formed. X‐ray structure determinations on single crystals of (Ph4P)2[Pt(N3)6] ( 1 ) (triclinic, space group P1, a = 10.175(1), b = 10.516(1), c = 12.380(2) Å, α = 87.822(9), β = 73.822(9), γ = 67.987(8)°, Z = 1) and (Ph4As)2[Pt(N3)Cl5] · HCON(CH3)2 ( 2 ) (triclinic, space group P1, a = 10.068(2), b = 11.001(2), c = 23.658(5) Å, α = 101.196(14), β = 93.977(15), γ = 101.484(13)°, Z = 2) have been performed. The bond lengths are Pt–N = 2.088 ( 1 ), 2.105 ( 2 ) and Pt–Cl = 2.318 Å ( 2 ). The approximate linear azido ligands with Nα–Nβ–Nγ‐angles = 173.5–174.6° are bonded with Pt–Nα–Nβ‐angles = 116.4–121.0°. In the vibrational spectra the PtCl stretching vibrations of (n‐Bu4N)2[Pt(N3)Cl5] are observed at 318–345, the PtN stretching modes of (n‐Bu4N)2[Pt(N3)6] at 401–428 and of (n‐Bu4N)2[Pt(N3)Cl5] at 408–413 cm–1. The mixtures (n‐Bu4N)2[Pt(15NN2)n(N215N)6–n], n = 0–6 and (n‐Bu4N)2[Pt(15NN2)Cl5]/(n‐Bu4N)2[Pt(N215N)Cl5] exhibit 15N‐isotopic shifts up to 20 cm–1. Based on the molecular parameters of the X‐ray determinations the vibrational spectra are assigned by normal coordinate analysis. The average valence force constants are fd(PtCl) = 1.93, fd(PtNα) = 2.38 and fd(NαNβ, NβNγ) = 12.39 mdyn/Å. In the 195Pt NMR spectrum of [Pt(N3)nCl6–n]2–, n = 0–6 downfield shifts with the increasing number of azido ligands are observed in the range 4766–5067 ppm. The 15N NMR spectrum of (n‐Bu4N)2[Pt(15NN2)n(N215N)6–n], n = 0–6 exhibits by 15N–195Pt coupling a pseudotriplett at –307.5 ppm. Due to the isotopomeres n = 0–5 for terminal 15N six well‐resolved signals with distances of 0.03 ppm are observed in the low field region at –201 to –199 ppm.  相似文献   

8.
Syntheses, Vibrational Spectra, and Normal Coordinate Analysis of Halogenonitrosylruthenates [Ru(NO)ClnBr5–n]2–, n = 0–5, and the Crystal Structure of (CH2py2)[Ru(NO)ClBr4] By treatment of [Ru(NO)Cl5]2– with anhydrous HBr in dichloromethane a mixture of [Ru(NO)ClnBr5–n]2–, n = 0–5, is formed, from which individual complexes can be separated by ion exchange chromatography on diethylaminoethyl cellulose. The X-Ray structure determination on a single crystal of (CH2py2)[Ru(NO)ClBr4] (monoclinic, space group P21/c, a = 11.480(2), b = 10.175(4), c = 16.025(6) Å, β = 107.40(1)°, Z = 4) reveals, that the chlorine atom is trans positioned to the nitrosyl group. The low temperature IR and Raman spectra have been recorded of six complexes of the series (n-Bu4N)2[Ru(NO)ClnBr5–n], n = 0–5, and are assigned by normal coordinate analysis. A good agreement between observed and calculated frequencies is achieved. The valence force constants are fd(NO) = 13.86–13.93 und fd(RuN) = 5.43–5.49 mdyn/Å.  相似文献   

9.
Preparation of Halogeno Pyridine Rhenates(III), [ReX6?n(Py)n](3?n)? (X = Br, Cl; n = 1?3) Crystal Structures of trans-[(C4H9)4N][ReBr4(Py)2], mer-[ReCl3(Py)3], and mer- [ReBr3(Py)3] The mixed halogeno-pyridine-rhenates(III), [ReX6?n(Py)n](3?n)? (X = Br, Cl), n = 1?3, have been prepared for the first time by reaction of the tetrabutylammoniumsalts (TBA)2[ReX6] (X = Br, Cl) in pyridine with (TBA)BH4 and separation by chromatography on Al2O3. Apart from the monopyridine complexes only the trans and mer isomers are formed from the bis-and tris-pyridine compounds. The X-ray structure determinations of the isotypic neutral complexes mer- [ReX3(Py)3] (monoclinic, space group P 21/n, Z = 4; for X = Cl: a = 9,1120(8), b = 12,5156(14), c = 15,6100(13) Å, β = 91,385(7)°; for X = Br: a = 9,152(5), b = 12,852(13), c = 15,669(2) Å, β = 90,43(2)°) reveal, due to the stronger trans influence of pyridine compared with Cl and Br, that the Re? X distances in asymmetric Py? Re? X3 axes with ReCl3 = 2,397 Å and ReBr3 = 2,534 Å are elongated by 1,3 and 1% in comparison with symmetric X1? Re? X2 axes with ReCl1 = ReCl2 = 2,367 Å and ReBr1 = 2,513 and ReBr2 = 2,506 Å, respectively. The Re? N bond lengths are roughly equal with 2,12 Å. Trans-(TBA)[ReBr4(Py)2] crystallizes triclinic, space group P1 , a = 9,2048(12), b = 12,0792(11), c = 15,525(2) Å, α = 95,239(10), β = 94,193(11), γ = 106,153(9)°, Z = 2. The unit cell contains two independent but very similar complex anions with approximate D2h(mmm) point symmetry.  相似文献   

10.
Thio and Amidothio Derivatives of Diphosphorus(IV) Acid Oxothiodiphosphates(IV) with anions [P2OnS6?n]4? (n = 1–5) are formed by steps wise substitution of thio by oxo ligands in hexathiodiphosphate(4–). Oxidative ammonolysis of thianion leads to amidothio derivatives, [P2(NH2)S5]3? and [P2(NH2)2S4]2?.  相似文献   

11.
The complexes of the type [ReH(CO)5–n(PMe3)n] (n = 4, 3) were reacted with aldehydes, CO2, and RC?CCOOMe (R = H, Me) to establish a phosphine-substitutional effect on the reactivity of the Re–H bond. In the series 1–3 , benzaldehyde showed conversion with only 3 to afford a (benzyloxy)carbonyltetrakis(trimethylphosphine)rhenium complex 4 . Pyridine-2-carbaldehyde allowed reaction with all hydrides 1–3 . With 1 and 2 , the same dicarbonyl[(pyridin-2-yl)methoxy-O, N]bis(trimethylphosphine)rhenium 5b was formed with the intermediacy of a [(pyridin-2-yl)methoxy-O]-ligated species and extrusion of CO or PMe3, respectively. The analogous conversion of 3 afforded the carbonyl[(pyridin-2-yl)methoxy-O,N]tris(trimethylphosphine)rhenium ( 1 ) 7b . While 1 did not react with CO2, 2 and 3 yielded under relatively mild conditions the formato-ligated [Re(HCO2)(CO)(L)(PMe3)3] species ( 8 (L = CO) and 9 (L = PMe3)). Methyl propiolate and methyl butynoate were transformed, in the presence of 1 , to [Re{C(CO2Me)?CHR}(CO)3(PMe3)2] systems ( 10a (R = H), and 10b (R = Me)), with prevailing α-metallation and trans-insertion stereochemistry. Similarly, HC≡CCO2Me afforded with 2 and 3 , the α-metallation products [Re{C(CO2Me)?CH2}(CO)(L)(PMe3)3] 11 (L = CO) and 12 (L = PMe3). The methyl butyonate insertion into 2 resulted in formation of a mixture of the (Z)- and (E)-isomers of [Re{C(CO2Me)?CHMe} (CO)2(PMe3)3] ( 13a , b ). In the case of the conversion of 3 with MeC?CCO2Me, a Re–H cis-addition product [Re{(E)-C(CO2Me)?CHMe}(CO)(PMe3)4] ( 14 ) was selectively obtained. Complex 11 was characterized by an X-ray crystal-structure analysis.  相似文献   

12.
采用密度泛函理论(DFT)研究了螺桨烷型分子BX[(CH2)n]3和BX(CH2)[CH(CH2)n CH](X=N,P;n=1-6)的结构、稳定性、化学键和电子光谱性质.计算结果表明这些分子都是稳定的.BX[(CH2)n]3(X=N,P;n=1-6)的最高占据分子轨道(HOMO)和最低空分子轨道(LUMO)之间的能隙均大于5.20 eV,其中BN[CH2]3和BP[CH2]3的能隙超过7.0 eV,与C5H6的能隙(7.27 eV)很接近,BX(CH2)[CH(CH2)n CH](X=N,P;n=1-6)的能隙在6.80 eV左右.所研究分子能量的二阶差分表明BN[(CH2)3]3、BP[(CH2)4]3及BX(CH2)[CH(CH2)2CH](X=N,P)是最稳定的.BX[(CH2)n]3的Wiberg键级表明除了BN[(CH2)n]3(n=2和6)中不存在B―N键,其它化合物中B和N均形成了化学键,BP[(CH2)n]3中除了BP[(CH2)2]3不存在B―P键,其它的均存在.电子密度的拓扑分析表明N―B键属于离子键,而P―B键具有共价键特征.BX[(CH2)n]3(X=N,P)的第一垂直激发能分别在191.1-284.8 nm和191.8-270.1 nm之间,BX(CH2)[CH(CH2)n CH](X=N,P)的第一垂直激发能分别在190.5-199.7 nm和209.0-221.3 nm之间.  相似文献   

13.
Disintegration of [Mo6Cl8−nIn]Cl4 in Complexes with n = 0–3 by Countercurrent Distribution [Mo6Cl8−nIn]Cl4 with n = 1–1, 2 have been disintegrated into [Mo6Cl8]Cl4, [Mo6Cl7I1]Cl4, [Mo6Cl6I2]Cl4, and [Mo6Cl5I3]Cl4 by means of the countercurrent distribution and the yields before and after annealing at 400°C are compared with probability calculation on the basis of possible permutationes. Annealing leads to the occupation of the ligand places in agreement with the calculation. The lattice constants of the dihydrates of the complexes mentioned above are determind.  相似文献   

14.
Dinuclear Palladium(II), Platinum(II), and Iridium(III) Complexes of Bis[imidazol‐4‐yl]alkanes The reaction of bis(1,1′‐triphenylmethyl‐imidazol‐4‐yl) alkanes ((CH2)n bridged imidazoles L(CH2)nL, n = 3–6) with chloro bridged complexes [R3P(Cl)M(μ‐Cl)M(Cl)PR3] (M = Pd, Pt; R = Et, Pr, Bu) affords the dinuclear compounds [Cl2(R3P)M–L(CH2)nL–M(PR3)Cl2] 1 – 17 . The structures of [Cl2(Et3P)Pd–L(CH2)3L–Pd(PEt3)Cl2] ( 1 ), [Cl2(Bu3P)Pd–L(CH2)4L–Pd(PBu3)Cl2] ( 10 ), [Cl2(Et3P)Pd–L(CH2)5L–Pd(PEt3)Cl2] ( 3 ), [Cl2(Et3P)Pt–L(CH2)3L–Pt(PEt3)Cl2] ( 13 ) with trans Cl–M–Cl groups were determined by X‐ray diffraction. Similarly the complexes [Cl2(Cp*)Ir–L(CH2)nL–Ir(Cp*)Cl2] (n = 4–6) are obtained from [Cp*(Cl)Ir(μ‐Cl)2Ir(Cl)Cp*] and the methylene bridged bis(imidazoles).  相似文献   

15.
16.
The electronic, bonding, and photophysical properties of one‐dimensional [CuCN]n (n = 1–10) chains, 2‐D [CuCN]n (n = 2–10) nanorings, and 3‐D [Cun(CN)n]m (n = 4, m = 2, 3; n = 10, m = 2) tubes are investigated by means of a multitude of computational methodologies using density functional theory (DFT) and time‐dependent‐density‐functional theory (TD‐DFT) methods. The calculations revealed that the 2‐D [CuCN]n (n = 2–10) nanorings are more stable than the respective 1‐D [CuCN]n (n = 2–10) linear chains. The 2‐D [CuCN]n (n = 2–10) nanorings are predicted to form 3‐D [Cun(CN)n]m (n = 4, m = 2, 3; n = 10, m = 2) tubes supported by weak stacking interactions, which are clearly visualized as broad regions in real space by the 3D plots of the reduced density gradient. The bonding mechanism in the 1‐D [CuCN]n (n = 1–10) chains, 2‐D [CuCN]n (n = 2–10) nanorings, and 3‐D [Cun(CN)n]m (n = 4, m = 2, 3; n = 10, m = 2) tubes are easily recognized by a multitude of electronic structure calculation approaches. Particular emphasis was given on the photophysical properties (absorption and emission spectra) of the [CuCN]n chains, nanorings, and tubes which were simulated by TD‐DFT calculations. The absorption and emission bands in the simulated TD‐DFT absorption and emission spectra have thoroughly been analyzed and assignments of the contributing principal electronic transitions associated to individual excitations have been made. © 2015 Wiley Periodicals, Inc.  相似文献   

17.
Perfluoromethyl-Element-Ligands. XVIII. Preparation and Spectroscopic Investigation of M(CO)5L and M(CO)4L2 Complexes [L = MenP(CF3)3?n; n = 0–3; M = Cr, Mo, W] M(CO)5L and cis-M(CO)4L2 complexes, respectively [M = Cr, Mo, W; L = MenP(CF3)3?n; n = 0–3] are prepared reacting M(CO)5 · THF or M(CO)4norbor with L at room temperature. The cis-compounds isomerize above 50°C yielding the trans-complexes; the rate of isomerization increases with increasing number of CF3 groups. Thermal reaction of M(CO)6 (M = Cr, Mo, W) with P(CF3)3 yields M(CO)5P(CF3)3 and trans-M(CO)4[P(CF3)3]2. Introduction of three P(CF3)3 ligands by reaction with M(CO)3(cycloheptatriene) (M = Cr, Mo) proves unsuccessful; besides little M(CO)5P(CF3)3 trans-M(CO)4[P(CF3)3]2 is formed. The new compounds are characterized by analytical and spectroscopic (n.m.r., i.r., MS) methods.  相似文献   

18.
Synthesis and Characterisation of the Siloxialanes [H2AlOSiMe3]n and [HAl(OtBu)(OSiMe3)]2 as well as the Use of [H2AlOSiMe3]n and [H2AlOtBu]2 as Reducing Agents for a Tin(II) Amide Following the synthesis of [H2AlOtBu]2 ( 1 ) and [HAl(OtBu)2]2 ( 2 ) the siloxialane [H2AlOSiMe3]n ( 3 ) was synthesized and has been subject to single crystal X‐ray analysis for the first time. The molecule 3 is tetrameric (n = 4) in solution and polymeric (n = ∞) in the solid state. 3 is also obtained together with the siloxide [Al(OSiMe3)3]2 ( 5 ) by the reaction of the aluminiumhydride with the double molar amount of trimethylsilanol. The expected monohydride [HAl(OSiMe3)2]2 ( 4 ) was not formed. The heteroleptic monohydride [HAl(OtBu)(OSiMe3)]2 ( 6 ) was synthesized by the reaction of 3 with an equimolar amount of tert‐butanol and was also generated by the addition of trimethylsilanol to an equimolar amount of the alkoxialane [H2AlOtBu]2 ( 1 ). Compound 6 was characterized by single crystal X‐ray diffraction analysis. Additionally we investigated the reducing force of the dihydrides 1 and 3 towards the cyclic diazastannylene Me2Si(NtBu)2Sn ( 7 ). In the course of this reaction SnII in 7 was reduced to elementary tin whereas the hydrides were oxidized to hydrogene. Tin is obtained in its β‐form as found by powder‐X‐ray diffraction. The shapes of the metal precipitates (porous, sponge‐like pieces or nanoscaled powders) depend on the conditions of reactions. Besides the elements the spirocyclic aminoalkoxialane [Me2Si(NtBu)2AlOtBu]2 ( 8 ) or aminosiloxialane [Me2Si(NtBu)2AlOSiMe3]2 ( 9 ) are formed. Structural details of the molecules 8 and 9 can be derived from single crystal X‐ray analyses.  相似文献   

19.
Triphenylphosphane Nickel(0) Complexes with Isocyanide Ligands — [(RNC)nNi(PPh3)4–n] (n = 1–3) Synthesis and properties of the isocyanide triphenylphosphane nickel(0) complexes [(RNC)Ni(PPh3)3], [(RNC)2Ni(PPh3)2] and [(RNC)3Ni(PPh3)] (R = tBu, Cy, PhCH2, p-TosCH2) are described. I.r. and 31P n.m.r. spectra were recorded and the X-ray crystal structure of [(PhCH2NC)2Ni(PPh3)2] was determined.  相似文献   

20.
Mesityl‐vanadium(III)‐phenolate Complexes: Synthesis, Structure, and Reactivity Protolysis reactions of [VMes3(THF)] with ortho‐substituted phenols (2‐iso‐propyl‐(H–IPP), 2‐tert‐butyl(H–TBP), 2,4,6‐trimethylphenol (HOMes) and 2,2′biphenol (H2–Biphen) yield the partially and fully phenolate substituted complexes [VMes(OAr)2(THF)2] (OAr = IPP ( 1 ), TBP ( 2 )), [VMes2(OMes)(THF)] ( 4 ), [V(OAr)3(THF)2] (OAr = TBP ( 3 ), OMes ( 5 )), and [V2(Biphen)3(THF)4] ( 6 ). Treatment of 6 with Li2Biphen(Et2O)4 results in formation of [{Li(OEt2)}3V(Biphen)3] ( 7 ) and with MesLi complexes [{Li(THF)2}2VMes(Biphen)2] · THF ( 8 ) and [{Li(DME)}VMes2(Biphen)] ( 9 ) are formed. Reacting [VCl3(THF)3] with LiOMes in 1 : 1 to 1 : 4 ratios yields the componds [VCl3–n(OMes)n(THF)2] (n = 1 ( 5 b ), 2 ( 5 a ), 3 ( 5 )) and [{Li(DME)2}V(OMes)4] ( 5 c ), the latter showing thermochromism due to a complexation/decomplexation equilibrium of the solvated cation. The mixed ligand mesityl phenolate complexes [{Li(DME)n}{VMes2(OAr)2}] (OAr = IPP ( 10 ), TBP ( 11 ), OMes ( 12 ) (n = 2 or 3) and [{Li(DME)2}{VMes(OMes)3}] ( 15 ) are obtained by reaction of 1 , 2 , 5 a and 5 with MesLi. With [{Li(DME)2(THF)}{VMes3(IPP)}] ( 13 ) a ligand exchange product of 10 was isolated. Addition of LiOMes to [VMes3(THF)] forming [Li(THF)4][VMes3(OMes)] ( 14 ) completes the series of [Li(solv.)x][VMes4–n(OMes)n] (n = 1 to 4) complexes which have been oxidised to their corresponding neutral [VMes4–n(OMes)n] derivatives 16 to 19 by reaction with p‐chloranile. They were investigated by epr spectroscopy. The molecular structures of 1 , 3 , 5 , 5 a , 5 a – Br , 7 , 10 and 13 have been determined by X‐ray analysis. In 1 (monoclinic, C2/c, a = 29.566(3) Å, b = 14.562(2) Å, c = 15.313(1) Å, β = 100.21(1)°, Z = 8), 3 (orthorhombic, Pbcn, a = 28.119(5) Å, b = 14.549(3) Å, c = 17.784(4) Å, β = 90.00°, Z = 8), ( 5 ) (triclinic, P1, a = 8.868(1) Å, b = 14.520(3) Å, c = 14.664(3) Å, α = 111.44(1)°, β = 96.33(1)°, γ = 102.86(1)°, Z = 2), 5 a (monoclinic, P21/c, a = 20.451(2) Å, b = 8.198(1) Å, c = 15.790(2) Å, β = 103.38(1)°, Z = 4) and 5 a – Br (monoclinic, P21/c, a = 21.264(3) Å, b = 8.242(4) Å, c = 15.950(2) Å, β = 109.14(1)°, Z = 4) the vanadium atoms are coordinated trigonal bipyramidal with the THF molecules in the axial positions. The central atom in 7 (trigonal, P3c1, a = 20.500(3) Å, b = 20.500(3) Å, c = 18.658(4) Å, Z = 6) has an octahedral environment. The three Li(OEt2)+ fragments are bound bridging the biphenolate ligands. The structures of 10 (monoclinic, P21/c, a = 16.894(3) Å, b = 12.181(2) Å, c = 25.180(3) Å, β = 91.52(1)°, Z = 4) and 13 (orthorhombic, Pna21, a = 16.152(4) Å, b = 17.293(6) Å, c = 16.530(7) Å, Z = 4) are characterised by separated ions with tetrahedrally coordinated vanadate(III) anions and the lithium cations being the centres of octahedral and trigonal bipyramidal solvent environments, respectively.  相似文献   

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