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1.
Insertion of Metal Fluorides in Organoindium Fluorides . The reaction of i-Pr2InCl ( 1 ) with CsF in acetonitrile at room temperature yields [(i-Pr2InF)5(CsF · 2 MeCN)] ([ 2 · 2 MeCN]). {[(MesInF2)10MgF2] · 5 toluene} ({ 3 · 5 toluene}) can be isolated as a by-product in the reaction of Mes3In with BF3 · OEt2 in the presence of MgBrCl. [ 2 · 2 MeCN] and { 3 · 5 toluene} were characterized by NMR spectroscopy as well as by X-ray structure determinations. [ 2 · 2 MeCN] forms infinite double chains of (i-Pr2InF)5-blocks and CsF-units. The coordination sphere of the cesium atom consists of three fluorine atoms and the nitrogen atoms of three acetonitrile molecules, which wrap the metal atom in a strongly distorted octahedral fashion. One of the acetonitrile molecules in [ 2 · 2 MeCN] has a μ2-bridging function. This results in the formation of four membered Cs2N2-rings. In { 3 · 5 toluene}, ten molecules of MesInF2 are forming a cage in which a linear MgF2-unit is inserted.  相似文献   

2.
Reaction of [UO2Cl2(THF)3] with 3 equivalents of LiC6Cl5 in Et2O resulted in the formation of first uranyl aryl complex [Li(Et2O)2(THF)][UO2(C6Cl5)3] ([Li][ 1 ]) in good yields. Subsequent dissolution of [Li][ 1 ] in THF resulted in conversion into [Li(THF)4][UO2(C6Cl5)3(THF)] ([Li][ 2 ]), also in good yields. DFT calculations reveal that the U−C bonds in [Li][ 1 ] and [Li][ 2 ] exhibit appreciable covalency. Additionally, the 13C NMR chemical shifts for their Cipso environments are strongly affected by spin-orbit coupling—a consequence of 5f orbital participation in the U−C bonds.  相似文献   

3.
Syntheses and Crystal Structures of Novel Heterobimetallic Tantalum Coin Metal Chalcogenido Clusters In the presence of phosphine the thiotantalats (Et4N)4[Ta6S17] · 3MeCN reacts with copper to give a number of new heterobimetallic tantalum copper chalcogenide clusters. These clusters show metal chalcogenide units some of which here already known from the chemistry of vanadium and niobium. New Ta—M‐chalcogenide clusters could also be synthesised by reaction of TaCl5 and silylated chalcogen reagents with copper or silver salts in presence of phosphine. Such examples are: [Ta2Cu2S4Cl2(PMe3)6] · DMF ( 1 ), (Et4N)[Ta3Cu5S8Cl5(PMe3)6] · 2MeCN ( 2 ), (Et4N)[Ta9Cu10S24Cl8(PMe3)14] · 2MeCN ( 3 ), [Ta4Cu12Cl8S12(PMe3)12] ( 4 ), (Et4N)[Ta2Cu6S6Cl5(PPh3)6] · 5MeCN ( 5 ), (Et4N)[Ta2Cu6S6Cl5(PPh2Me)6] · 2MeCN ( 6 ), (Et4N)[Ta2Cu6S6Cl5(PtBu2Cl)6] · MeCN ( 7 ) [Ta2Cu2S4Br4(PPh3)2(MeCN)2] · MeCN ( 8 ), [Cu(PMe3)4]2[Ta2Cu6S6(SCN)6(PMe3)6] · 4MeCN ( 9 ), [TaCu5S4Cl2(dppm)4] · DMF ( 10 ), [Ta2Cu2Se4(SCN)2(PMe3)6] ( 11 ), [Cu(PMe3)4]2[Ta2Cu6Se6(SCN)6(PMe3)6] · 4MeCN ( 12 ), [TaCu4Se4(PnPr3)6][TaCl6] ( 13 ), [Ta2Ag2Se4Cl2(PMe3)6] · MeCN ( 14 ), [TaAg3Se4(PMe3)3] ( 15 ). The structures of these compounds were obtained by X‐ray single crystal structure analysis.  相似文献   

4.
Syntheses and Structure Elucidations of Novel (Ironcarbonyl)zinc and ‐cadmium Chloride Derivatives Reactions of zinc/cadmium chloride with Na2[Fe(CO)4] lead to a number of new (iron carbonyl)zinc/cadmium chlorides, wherein the reaction course depends on the used solvent used. In the reaction of ZnCl2 with Na2[Fe(CO)4], three new substances can be prepared. The compound [Zn2Cl2Fe(CO)4(THF)2] ( 1 ), which consists of neutral polymeres, is formed in THF, the ionic compound [Na(DME)3][Zn2Cl3Fe(CO)4] ( 2 ) forms in DME, and from a mixture of THF and TMEDA the compound [Zn2Cl2Fe(CO)4(TMEDA)2] ( 3 ) is obtained as a monomere. Also by using CdCl2, the reaction with Na2[Fe(CO)4] in THF leads to the polymeric compound ([(Cd4Cl6)Fe(CO)4(THF)5] ( 4 )). Carrying out the reaction in a mixture of toluene and DME leads to the formation of the ionic compound [Na(DME)3]2[Cd6{Fe(CO)4}6Cl2(DME)2] ( 5 ) in which an annular dianion consisting of twelve metal atoms is found. From an aqueous solution and subsequent work‐up in THF, the compound [Fe(THF)4(H2O)2][Cd8{Fe(CO)4}4Cl9(THF)6]2 ( 6 ) can be prepared which contains an cluster anion that is built of anellated six membered rings.  相似文献   

5.
Recent studies on solvent effects on electrochemical partial fluorination are reviewed. At first, the historical background and some problems of electrochemical fluorination in organic solvents like acetonitrile (MeCN) are briefly mentioned. Ethereal solvents like dimethoxyethane (DME) and a mixture of DME and MeCN were found to improve both the yield and current efficiency for electrochemical fluorination since these solvent systems effectively suppress anode passivation and overoxidation of fluorinated products once formed during the electrolysis. It was also found that DME stabilizes radical cationic intermediates of 4-arylthio-1,3-dioxolan-2-ones and 3-phenylthiophthalide leading to α-fluorination while dichloromethane (CH2Cl2) destabilizes them leading to fluorodesulfurization. On the other hand, imidazolium ionic liquids and liquid fluoride salts like Et4NF·4HF and Et3N·5HF exhibited similar effects to CH2Cl2. Selective fluorination of hardly oxidizable phthalide was also achieved using a combination of two kinds of ionic liquids (imidazolium triflate and liquid fluoride salts).  相似文献   

6.
Synthesis and Characterization of Fluorenyl Gallates and Fluorenyl Indates GaCl3 reacts with Fluorenyllithium (LiFl) in the ratio 1:4 in Et2O to [Li(THF)4][GaFl4] ( 1 ). The addition of DME (1,2-dimethoxyethane) to solutions of 1 in THF leads to [Li(DME)3][GaFl4] ( 2 ) under replacement of THF molecules by DME molecules in the coordination sphere of the Li+ ions. Treatment of InCl with LiFl in Et2O and recrystallization from THF gives [Li(THF)4][ClInFl3] ( 3 ), which is formed by an disproportionation reaction. 3 can also be obtained by the reaction of InCl with FlZnCl/LiCl in Et2O and recrystallization from THF. 1 and 2 crystallize from THF and THF/DME as [Li(THF)4][GaFl4] · THF ( 1 · THF) and [Li(DME)3][GaFl4] · THF ( 2 · THF), respectively. Crystalline 3 is isolated from the reaction of InCl and FlZnCl/LiCl, while the reaction mixture of InCl and LiFl gives after recrystallization in THF 3 · 1,5 THF. The gallate ions in 1 and 2 differ mainly in the position of the fluorenyl ligands. The unit cells of 3 and 3 · 1,5 THF contain two crystallographic unique ion pairs of [Li(THF)4][ClInFl3].  相似文献   

7.
The reaction of equimolar amounts of YC13 and [1,8-C10H6(NSiMe3)2]Li2 in THF produced the complex {[1,8-C10H6(NSiMe3)2YCl(DME)]2(μ-Cl)}[Li(DME)3] (1), which was isolated by recrystallization from a DME—hexane mixture as yellow crystals in 82% yield. The reaction of complex 1 with (Me3Si)2NLi(Et20) (in a molar ratio of 1:2) in toluene gave the corresponding amide derivative [1,8-C10H6(NSiMe3)2YN(SiMe3)2(μ-Cl)]2[Li(DME)3]2 (2). The recrystallization of the reaction product from toluene afforded complex 2 in 73% yield. The X-ray diffraction study showed that in the crystalline state, compounds 1 and 2 consist of the isolated cationic and anionic moieties. The complex anions are dinuclear moieties with the bridging chlorine ligands.  相似文献   

8.
The important role of supporting solvent in transmetallation reactions involving Grignard reagents is highlighted in the formation and crystallisation of the Group 13 ‘ate’ species, [Mg3Br3Cl2(Et2O)6][GaPh2Br2] (1), [Mg3Br5(Et2O)6][InPh2Br2] (2), [MgBr(THF)5][GaPh3Br] (3), [MgBr(THF)5][InPh3Br] (4), [Mg(THF)6][GaPh2Br2]2 (5) obtained by reaction of PhMgBr with gallium and indium halides. The compounds have been characterised by 1H NMR, elemental analyses, and single-crystal X-ray diffraction.  相似文献   

9.
Chiral Gallium and Indium Alkoxometalates Li2(S)‐BINOLate ((S)‐BINOL = (S)‐(–)‐2,2′‐Dihydroxy‐1,1′‐binaphthyl) generated by dilithiation of (S)BINOL with two equivalents nBuLi was reacted with GaCl3 und InCl3 in THF to the alkoxometalates [{Li(THF)2}{Li(THF)}2{Ga((S)‐BINOLate)3}] ( 1 ) and [{Li(THF)2}2{Li(THF)}{In((S)‐BINOLate)3}] · [{Li(THF)2}{Li(THF)}2{In((S)‐ BINOLate)3}]2 ( 3 ), respectively. 1 and 3 crystallize from THF/toluene mixtures as 1 · 2 toluene and 3 · 8 toluene. The treatment of PhCH2GaCl2 with Li2(S)‐BINOLate in THF under reflux, followed by recrystallization of the product from DME gives the gallate [{Li(DME)}3{Ga((S)BINOLate)3}] · 1.5 THF ( 2 · 1.5 THF). 1 – 3 were characterized by NMR, IR and MS techniques. In addition, 1 · 2 toluene, 2 · 1.5 THF and 3 · 8 toluene were investigated by X‐ray structure analyses. According to them, a distorted octahedral coordination sphere around the group 13 metal was formed, built‐up by three BINOLate ligands. The three Li+ counter ions act as bridging units by metal‐oxygen coordination. The coordination sphere of the Li+ ions was completed, depending on the available space, by one or two THF ligands ( 1 · 2 toluene, 3 · 8 toluene) and one DME ligand ( 2 · 1.5 THF), respectively. The sterical dominance of the BINOLate ligands can be shown by the almost square‐planar coordination of the Li+ ions in 2 · 1.5 THF giving a small twisting angle of only 17°.  相似文献   

10.
Interaction of ptert‐butylcalix[8]areneH8 (L8H8) with [NaVO(OtBu)4] (formed in situ from VOCl3) afforded the complex [Na(NCMe)5][(VO)2L8H]?4 MeCN ( 1 ?4 MeCN). Increasing [NaVO(OtBu)4] to 4 equiv led to [Na(NCMe)6]2[(Na(VO)4L8)(Na(NCMe))3]2?10 MeCN ( 2 ?10 MeCN). With adventitious oxygen, reaction of 4 equiv of [VO(OtBu)3] with L8H8 afforded the alkali‐metal‐free complex [(VO)4L83‐O)2] ( 3 ); solvates 3 ?3 MeCN and 3 ?3 CH2Cl2 were isolated. For the lithium analogue, the order of addition had to be reversed such that lithium tert‐butoxide was added to L8H8 and then treated with 2 equiv of VOCl3; crystallisation afforded [(VO2)2Li6[L8](thf)2(OtBu)2(Et2O)2]?Et2O ( 4 ?Et2O). Upon extraction into acetonitrile, [Li(NCMe)4][(VO)2L8H]?8 MeCN ( 5 ?8 MeCN) was formed. Use of the imido precursors [V(NtBu)(OtBu)3] and [V(Np‐tolyl)(OtBu)3] and L8H8, afforded [tBuNH3][{V(p‐tolylN)}2L8H]?3 1/2 MeCN ( 6 ?3 1/2 MeCN). The molecular structures of 1 to 6 are reported. Complexes 1 , 3 , and 4 were screened as precatalysts for the polymerisation of ethylene in the presence of cocatalysts at various temperatures and for the copolymerisation of ethylene with propylene. Activities as high as 136 000 g (mmol(V) h)?1 were sometimes achieved; higher molecular weight polymers could be obtained versus the benchmark [VO(OEt)Cl2]. For copolymerisation, incorporation of propylene was 7.1–10.9 mol % (compare 10 mol % for [VO(OEt)Cl2]), although catalytic activities were lower than [VO(OEt)Cl2].  相似文献   

11.
Treatment of CrCl3(THF)3 with KPzTp in THF affords of the compound K[Cr(PzTp)Cl3], and the K+ in this complex can be replaced by Et4N+ in CH2Cl2. Well-defined green crystals of [Et4N]r(PzTp)Cl3] (I) suitable for X-ray diffraction are obtained at −20°C. In the anion the metal center shows a distorted octahedral geometry with the tetra(pyrazolyl) borate bonded as three N-donor tripod ligands and three chloride atoms completing the coordination sphere.  相似文献   

12.
2‐(Methylthio)aniline (H2L1) and 2‐(phenylthio)aniline (H2L2) were treated with n‐butyllithium to yield the corresponding anilides [LiHL1] and [LiHL2]. Recrystallization from diethyl ether and THF afforded the solvates [LiHL1(Et2O)] and [LiHL2(THF)2]. The X‐ray crystal structure determination revealed dimeric molecules which exhibit a centrosymmetric Li2N2 ring. In the case of [LiHL1(Et2O)] the SMe group is involved in Li coordination and in the case of [LiHL2(THF)2] the SPh group is part of an intramolecular N–H ··· S hydrogen bridge. The sodium anilides [NaHL1(DME)] and [NaHL2(DME)] were obtained from the reaction of H2L1 and H2L2 with sodium amide in DME as solvent. Like in the case of the lithium amides the sodium derivatives [NaHL1(DME)] and [NaHL2(DME)] display centrosymmetric Na2N2 cores. The coordination sphere of the sodium atoms is completed by DME molecules, which act as chelating ligands. In the case of [NaHL1(DME)] the DME molecules enable additionally a linkage of the dimeric subunits to give a chain structure. The potassium derivatives [KNHL1] and [KNHL2(DME)] were obtained from H2L1 and H2L2 and potassium hydride in DME as solvent. [KNHL1] displays a distinct structure based on [(KNHL1)2] dimers, which are linked by additional [KNHL1] units to give a 3D coordination polymer with {4.8.16(3)} topology. [KNHL2(DME)] forms dimers linked by bridging DME molecules to give a chain‐like coordination polymer.  相似文献   

13.
Syntheses and Crystal Structures of new Amido- und Imidobridged Cobalt Clusters: [Li(THF)2]3[Co32-NHMes)3Cl6] (1), [Li(DME)3]2[Co184-NPh)33-NPh)12Cl3] (2), [Li(DME)3]2[Co64-NPh)(μ2-NPh)6(PPh2Et)2] (3), and [Li(THF)4][Co83-NPh)62-NPh)3(PPh3)2] (4) The reactions of cobalt(II)-chloride with the lithium-amides LiNHMes and Li2NPh leads to an amido-bridged multinuclear complex [Li(THF)2]3[Co32-NHMes)3Cl6] ( 1 ) as well as to the imido-bridged cobalt cluster [Li(DME)3]2[Co184-NPh)33-NPh)12Cl3] ( 2 ). In the presence of tertiary phosphines two imido-bridged cobalt clusters [Li(DME)3]2[Co64-NPh)(μ2-NPh)6(PPh2Et)2] ( 3 ) and [Li(THF)4][Co83-NPh)62-NPh)3(PPh3)2] ( 4 ) result. The structures of 1 – 4 were characterized by X-ray single crystal structure analysis.  相似文献   

14.
The metathesis reaction of the magnesium complex [(dpp-BIAN)2−Mg2+(THF)3] (dpp-BIAN is 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene) with one equivalent of AlCl3 in toluene gave the [(dpp-BIAN)2−AlCl2][Mg2Cl3(THF)6]+ complex (1). Reduction of dpp-BIAN with aluminum metal in the presence of AlCl3 and AlI3 in toluene and diethyl ether afforded the radical-anionic complex [(dpp-BIAN)AlCl2] (2) and the dianionic complexes [(dpp-BIAN)2−AlI(Et2O)] (3) and [(dpp-BIAN)2−AlCl(Et2O)] (4), respectively. Compounds 1–4 were isolated in the crystalline state and characterized by IR spectroscopy and elemental analysis. The structures of compounds 1–3 were established by X-ray diffraction. Compound 2 was characterized by ESR spectroscopy. Compounds 3 and 4 were studied by 1H and 13C NMR spectroscopy. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 409–415, March, 2006.  相似文献   

15.
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   

16.
Synthesis and Structures of the Multinuclear Rhenium Nitrido Complexes [Re2N2Cl4(PMe2Ph)4(MeCN)] and [Re4N3Cl9(PMe2Ph)6] The binuclear rhenium complex [Re2N2Cl4(PMe2Ph)4(MeCN)] ( 1 ) is obtained as a byproduct of the synthesis of [(Me2PhP)3(MeCN)ClReNZrCl5] from [ReNCl2(PMe2Ph)3] and [ZrCl4(MeCN)2] in toluene. It crystallizes as 1 · 2 toluene in the monoclinic space group P21/n with a = 1517.0(3); b = 1847.7(2); c = 1952.4(6) pm; β = 106.44(1)° and Z = 4. The two Re atoms are connected by an asymmetric nitrido bridge Re≡N–Re with distances Re–N of 169.9(5) and 208.7(5) pm. In course of the reaction of [ReNCl2(PMe2Ph)3] with [ZrCl4(THF)2] in CH2Cl2 hydrochloric acid is formed by acting of the Lewis acid on the solvent. HCl protonates and eliminates phosphine ligands of the educt [ReNCl2(PMe2Ph)3] to form the phosphonium salt [PMe2PhH]2[ZrCl6] ( 2 ). It crystallizes in the monoclinic space group C2/c with a = 1536.9(3); b = 1148.8(1); c = 1402.2(3) pm, β = 100.70(2)° and Z = 4. The remaining fragments of the rhenium complex combine to yield the tetranuclear mixed valent complex [Re4N3Cl9(PMe2Ph)6] ( 3 ), crystallizing as 3 · CH2Cl2 in the triclinic space group P 1 with a = 1312.9(19); b = 1661.4(2); 1897.1(2) pm; α = 78.62(1)°; β = 86.77(1)°; γ = 68.28(1)° and Z = 2. The four Re atoms occupy the corners of a tetrahedron. Its edges are formed by three nitrido and three chloro bridges. The asymmetric nitrido bridges Re≡N–Re are characterized by short distances in the range of 172(2) to 176(3) pm and long distances of 194(3) to 204(2) pm. The angles Re–N–Re are between 154(1) and 160(1)°.  相似文献   

17.
CsF as Fluoridation Agent for Organometal Compounds of the Elements of Group 13 Cs[i-Bu3AlF] ( 1 ) can be obtained by the reaction of Al(i-Bu)3 with CsF in toluene. In a halide exchange reaction of Mes*GaCl2 with CsF in acetonitrile not the desired product Mes*GaF2 (Mes* = 2,4,6-(t-Bu)3C6H2) was isolated but the metalate Cs[Mes*GaF3] ( 2 ), formed by the addition of a third unit CsF. A ligand distribution was observed by the treatment of [(PhCH2)2GaTe(t-Bu)]2 with CsF in THF. The triorganofluoro gallate [Cs{(PhCH2)3GaF}]2 ( 3 ) was isolated. The triorganofluoro gallate Cs[Me3GaF] does not react with dry O2 in THF. With S8 in THF a reaction was achieved and the diorganodifluoro gallate [Cs(THF)0,5(Me2GaF2)] ( 4 ) could be characterized. The treatment of MesInBr2 with CsF in acetonitrile gives as only identified compound the indate Cs[MesInBr3] ( 5 ).  相似文献   

18.
Synthesised by refluxing the amine adduct [Me3Al·(PhCH2)2NLi·HN(CH2Ph)2] in toluene/THF, the title compound has been structurally characterised by X-ray diffraction, and the methane elimination/amide insertion processes involved in its formation have been modelled theoretically through a series of ab initio MO calculations.  相似文献   

19.
New homoligand and mixed‐ligand adducts of the heavier alkaline earth metal (Ca, Sr, Ba) halides with oxygen‐donor polyether ligands have been isolated and characterized and are compared with previously obtained compounds of the same class in order to give an overview on structures and properties. Homoligand halide adducts, discussed herein, are [CaI(DME)3]I ( 1 ), trans‐[SrI2(DME)3] ( 2 ), trans‐[BaI2(DME)3] ( 3 ), (DME = ethylene glycol dimethyl ether), [CaI(diglyme)2]I ( 4 ), cis‐[SrI2(diglyme)2] ( 5 ), trans‐[BaI2(diglyme)2] ( 6 ),(diglyme = diethylene glycol dimethyl ether, [SrI(triglyme)2]I ( 7 ), and [BaI(triglyme)2]I ( 8 ), (triglyme = triethylene glycol dimethyl ether). Introduction of the mono‐coordinating THF ligand (THF = tetrahydrofuran) in the coordination sphere of 1 , 2 , 3 , 4 allows the formation of the new mixed‐ligand compounds trans‐[CaI2(DME)2(THF)] ( 9 ), trans‐[SrI2(DME)2(THF)] ( 10 ), trans‐[BaI2(DME)2(THF)2] ( 11 ), and trans‐[CaI2(diglyme)2(THF)2] ( 12 ). These compounds were obtained from the metal halide salts in solution with pure or mixtures of ether solvents. While compounds 1 – 8 appear to be very stable and non‐reactive, adducts 9 – 12 present a comparable reactivity to the well known THF adducts [MI2(thf)n] (M = Ca, n = 4; Sr, Ba, n = 5).  相似文献   

20.
Three new hexanuclear Fe(III) coordination wheels [Fe6Cl6(L1)6]·5(MeCN) (1), [Na0.5Fe6Cl6(L1)6](N3)0.5·4.5(MeCN) (2), and [Fe6Cl6(L2)6]·2(MeCN) (3) have been synthesized with new prepared amino-acetonitrile derivatives 2-[bis(2-hydroxyethyl)amino]acetonitrile hydrochloride (H2L1) and 3-[bis(2-hydroxyethyl)amino]propanenitrile hydrochloride (H2L2). They were structurally characterized by single-crystal X-ray diffraction. Mößbauer spectroscopy and magnetic susceptibility measurements indicate dominant antiferromagnetic behavior between the Fe(III) centers.  相似文献   

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