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1.
The C-amidoalkylation of p-cresol with 4-chloro-N-(2,2-dichloro-2-phenylethylidene)benzenesulfon-amide in the presence of H2SO4, oleum, or a mixture of H2SO4 and P4O10 was studied for the first time. It was shown that the reaction not only leads to the targeted 4-chloro-N-[2,2-dichloro-1-(2-hydroxy-5-methylphenyl)-2-phenylethyl]benzenesulfonamide but is also accompanied by unexpected formation of the heterocyclic derivatives 4-chloro-N-(5-methyl-2-phenyl-1-benzofuran-3-yl)benzenesulfonamide and 5-methyl-3-phenyl-2-benzofuran-2(3H)-one.  相似文献   

2.
Suzuki–Miyaura coupling reaction of BrC6H4-X-C6H4Br 1 (X=CH2, CO, N-Bu, O, S, SO, and SO2) with arylboronic acid 2 was investigated in the presence of tBu3PPd precatalyst and CsF/[18]crown-6 as a base to establish whether or not the Pd catalyst can undergo catalyst transfer on these functional groups. In the reaction of 1 (X=CH2, CO, N-Bu, O, and SO2) with 2 , aryl-disubstituted product 3 (Ar-C6H4-X-C6H4-Ar) was exclusively obtained, indicating that the Pd catalyst undergoes catalyst transfer on these functional groups. On the other hand, the reaction of 1 e (X=S) and 1 f (X=SO) with 2 afforded only aryl-monosubstituted product 4 (Ar-C6H4-X-C6H4-Br) and a mixture of 3 and 4 , respectively, indicating that S and SO interfere with intramolecular catalyst transfer. Furthermore, we found that Suzuki–Miyaura polycondensation of 1 (X=CH2, CO, N-Bu, O, and SO2) and phenylenediboronic acid 5 in the presence of tBu3PPd precatalyst afforded high-molecular-weight polymer even when excess 1 was used. The polymers obtained from 1 (X=CH2, N-Bu, and O) and 5 turned out to be cyclic.  相似文献   

3.
Products from the reaction of 11-dihomodriman-8α-ol-12-one with several reagents such as MeSO3SiMe3, CF3SO3SiMe3, Sc(CF3SO3)3, conc. H2SO4 in EtOH (30% solution), and Amberlist-15 ion-exchange resin were studied. 11-Dihomodrim-8(9)-en-12-one and its oxime were synthesized. The reaction of its oxime with H3PO4 (86%) or CF3CO2H produced (1S,2S,4aS,8aS)-2,5,5,8a-tetramethyldecahydro-1H-naphtho [1,2-e]-3-methyl-4,5-dihydro-[1,2,6]-oxazine; with p-TsCl in Py, (1S,2S,4aS,8aS)-2,5,5,8a-tetramethyldecahydro-1H-naphtho[1,2-d]-2-methylpyrroline-N-oxide; and with PCl5 in Et2O, 11-acetylaminodrim-8(9)-ene and 11-methylaminooxodrim-8(9)-ene.  相似文献   

4.
Catalysis with water-soluble rhodium complexes, RhCl(CO)(TPPMS)2, [TPPMS = P(C6H5)2(C6H4SO3)] (1), RhCl(CO)(TPPDS)2, [TPPDS = P(C6H5)(C6H4SO3)2] (2) and RhCl(CO)(TPPTS)2, [TPPTS = P(C6H4SO3)3] (3) in hydroformylation of 1-hexene, 2-pentene, 2,3-dimethyl-1-butene, cyclohexene and several mixtures of these olefins have been studied, under moderate reaction conditions (T: 50–150 °C; pCO/pH2 = 1; total p: 14–68 bar; Substrate/Catalyst: 600/1) in biphasic toluene/water media. The catalytic system shows high activity but low selectivity. The linear and branched oxygenated products obtained are equally useful in naphtha upgrading, as observed in the real El Palito naphtha tried. The catalysts can be recycled several times without significant activity loss.  相似文献   

5.
Contact with SO2 causes almost immediate dissolution of tetraalkylammonium halides, R4NX, (R = CH3 (Me), X = I; R = C2H5 (Et), X = Cl, Br, I; R = C4H9 (nBu), X = Cl, Br), with the formation of an adduct, [R4N]+[(SO2)nX] (n = 1–4). Vapor pressure measurements indicate the proclivity for SO2 uptake follows the order N(CH3)4+ < N(C2H5)4+ < N(C4H9)4+. This trend is in accord with the Jenkins–Passmore volume‐based thermodynamic model. Born–Haber cycles, incorporating the lattice energy and gas phase energy terms, are used to evaluate the energetic feasibility of reactions. Density functional theory calculations (B3PW91; 6‐311+G(3df)) have been used to calculate the energetics of (SO2)nX (X = Cl and Br) anions in the gas phase. The experimental studies show that tetraalkylammonium halides are feasible sorbents for SO2. In order to correlate the theoretical model, experimental enthalpy, Δr and entropy, Δr changes have been determined by the van't Hoff method for the binding of one SO2 molecule to (C2H5)4NCl, resulting in the liquid adduct (C2H5)4NCl · SO2. The structure of the analogous 1:1 bromide adduct, (C2H5)4NBr · SO2, has been determined by single‐crystal X‐ray diffraction (monoclinic, P21/c, a = 9.1409(14) Å, b = 12.3790(19) Å, c = 11.3851(17) Å, β = 107.952(2)°, V = 1225.6(3) Å3). The structure consists of discrete alkylammonium cations, bromide anions and SO2 molecules with short contacts between the anion and SO2 molecules. The (C2H5)4N+ cationadopts a transoid conformation with D2d symmetry, and represents a rare example of a well‐ordered (C2H5)4N+ cation in a crystal structure. The Br anions and SO2 molecules forms a chain, (SO2Br)n, with bifurcated contacts. Non‐bonding electron pairs on the halide anions engage in electrostatic interactions with the sulfur atoms and charge‐transfer interactions with the antibonding S–O orbitals of the bound SO2 moiety. Raman and 17O NMR spectra provide compelling evidence for a charge‐transfer interaction between SO2 molecules and the halide ions.  相似文献   

6.
IntroductionMolecularpolymerwithonedimensionalormultidimen sionalstructureassemblingthroughhydrogenbondsisanim portantresearchcontentinthesupramolecularchemistryandcrystalenginnering .1,2 Withthedevelopmentofnewtypefunctionalmaterialssuchasmolecularmagnetic ,selectedcatalysis ,reversiblecatalysis ,reversiblehost guestmolecular(ion)exchangeetc.,3themoleculardesignandsynthesishavealreadyattractedconsiderableattentioninsupramolecu larsystem .Thesupramolecularcomplexesandorganiccom poundscontainin…  相似文献   

7.
合成和表征了5个螺旋配位聚合物{[Cu(Hbpma)(H2O)4]2(SO4)3·3.5H2O}n (1)、{[Ni(Hbpma)(H2O)4]4(SO4)6·10.75H2O}n (2)、{[Mn(Hbpma)(H2O)4](SO4)1.5·3H2O}n (3)、{[Zn(Hbpma)(H2O)4]4(SO4)6·4H2O·4CH3OH}n (4)和{[Cu(Hbpma)2(H2O)2](SO4)2·9H2O}n (5), 其中bpma代表N,N'-双(3-吡啶甲基)胺。晶体结构分析表明配合物1~4为一维链状结构, 配合物5为二维层状结构, 其中金属离子由质子化的bpma配体桥连。值得注意的是, 采取反-反式构象的柔性bpma配体使得配合物12为假螺旋链结构, 配合物34为螺旋链结构, 配合物5为螺旋层结构。同时研究了配合物的磁性和热稳定性。  相似文献   

8.
Two uranyl sulfate hydrates, (H3O)2[(UO2)2(SO4)3(H2O)] · 7H2O (NDUS) and (H3O)2[(UO2)2(SO4)3(H2O)] · 4H2O (NDUS1), and one uranyl selenate‐selenite [C5H6N][(UO2)(SeO4)(HSeO3)] (NDUSe), were obtained and their crystal structures solved. NDUS and NDUSe result from reactions in highly acidic media in the presence of L ‐cystine at 373 K. NDUS crystallized in a closed vial at 278 K after 5 days and NDUSe in an open beaker at 278 K after 2 weeks. NDUS1 was synthesized from aqueous solution at room temperature over the course of a month. NDUS, NDUS1, and NDUSe crystallize in the monoclinic space group P21/n, a = 15.0249(4) Å,b = 9.9320(2) Å, c = 15.6518(4) Å, β = 112.778(1)°, V = 2153.52(9) Å3,Z = 4, the tetragonal space group P43212, a = 10.6111(2) Å,c = 31.644(1) Å, V = 3563.0(2) Å3, Z = 8, and in the monoclinic space group P21/n, a = 8.993(3) Å, b = 13.399(5) Å, c = 10.640(4) Å,β = 108.230(4)°, V = 1217.7(8) Å3, Z = 4, respectively.The structural units of NDUS and NDUS1 are two‐dimensional uranyl sulfate sheets with a U/S ratio of 2/3. The structural unit of NDUSe is a two‐dimensional uranyl selenate‐selenite sheets with a U/Se ratio of 1/2. In‐situ reaction of the L ‐cystine ligands gives two distinct products for the different acids used here. Where sulfuric acid is used, only H3O+ cations are located in the interlayer space, where they balance the charge of the sheets, whereas where selenic acid is used, interlayer C5H6N+ cations result from the cyclization of the carboxyl groups of L ‐cystine, balancing the charge of the sheets.  相似文献   

9.
Syntheses, crystal structures and thermal behavior of two new hydrated cerium(III) sulfates are reported, Ce2(SO4)3·4H2O ( I ) and β‐Ce2(SO4)3·8H2O ( II ), both forming three‐dimensional networks. Compound I crystallizes in the space group P21/n. There are two non‐equivalent cerium atoms in the structure of I , one nine‐ and one ten‐fold coordinated to oxygen atoms. The cerium polyhedra are edge sharing, forming helically propagating chains, held together by sulfate groups. The structure is compact, all the sulfate groups are edge‐sharing with cerium polyhedra and one third of the oxygen atoms, belonging to sulfate groups, are in the S–Oμ3–Ce2 bonding mode. Compound II constitutes a new structure type among the octahydrated rare‐earth sulfates which belongs to the space group Pn. Each cerium atom is in contact with nine oxygen atoms, these belong to four water molecules, three corner sharing and one edge sharing sulfate groups. The crystal structure is built up by layers of [Ce(H2O)4(SO4)]nn+ held together by doubly edge sharing sulfate groups. The dehydration of II is a three step process, forming Ce2(SO4)3·5H2O, Ce2(SO4)3·4H2O and Ce2(SO4)3, respectively. During the oxidative decomposition of the anhydrous form, Ce2(SO4)3, into the final product CeO2, small amount of CeO(SO4) as an intermediate species was detected.  相似文献   

10.
IntroductionThereisatremendousactivityforthepastyearsintheareaofinorganic organichybridmaterialsinviewoftheirdi versifiedstructuresandinterestingproperties.1,2 Theeffortshavebeenmadeinsynthesizingandcharacterizingtheclassofmaterials.3Thecontrolofinorganicstructurebyanorganiccomponentrevealsaninteractivestructuralrelationinthema terials .4 Assemblyofaninorganic organichybridmaterialcanbeachievedbyselectingorganiccomponents (multidentateligands)andinorganiccomponents (transitionmetalions ,metalo…  相似文献   

11.
The title compound, cobalt 4′,7-diethoxylisoflavone-3′-sulfonate([Co(H2O)6](X)2⋅8H2O, X = C19H17O4SO3) was synthesized and its structure was determined by single-crystal X-ray diffraction analysis. It crystallizes in the triclinic space group P-1 with cell parameters a = 9.026(3) Å, b = 16.431(5) Å, c = 18.195(6) Å, α = 72.289(4), β = 87.498(4), γ = 82.775(5), V = 2550.1(13) Å−3, Dc = 1.419 Mg m−3, and Z = 2. The results show that the title compound consists of one cobalt cation, six coordinated water molecules, eight lattice water molecules, and two 4′,7-diethoxylisoflavone-3′-sulfonate anions, C19H17O4SO3. Two anions have different conformations. Twelve H atoms of six coordinated water molecules, as donors, form hydrogen bonds with four oxygen atoms of sulfo-groups of two anions and eight oxygen atoms of eight lattice water molecules. In addition, π < eqid1 > ⋅ < eqid2 > π stacking interactions exist in the crystal structure, which together with hydrogen bonds lead to supramolecular formation with a three-dimensional network.  相似文献   

12.
合成和表征了5个螺旋配位聚合物{[Cu(Hbpma)(H2O)4]2(SO4)3·3.5H2O}n (1)、{[Ni(Hbpma)(H2O)4]4(SO4)6·10.75H2O}n (2)、{[Mn(Hbpma)(H2O)4](SO4)1.5·3H2O}n (3)、{[Zn(Hbpma)(H2O)4]4(SO4)6·4H2O·4CH3OH}n (4)和{[Cu(Hbpma)2(H2O)2](SO4)2·9H2O}n (5),其中bpma代表N,N'-双(3-吡啶甲基)胺。晶体结构分析表明配合物1~4为一维链状结构,配合物5为二维层状结构,其中金属离子由质子化的bpma配体桥连。值得注意的是,采取反-反式构象的柔性bpma配体使得配合物12为假螺旋链结构,配合物34为螺旋链结构,配合物5为螺旋层结构。同时研究了配合物的磁性和热稳定性。  相似文献   

13.
A group of rofecoxib analogs, having a sulfonylazide (SO2N3) substituent in place of the methanesulfonyl (SO2CH3) pharmacophore at the meta‐position viz 3‐(4‐methyl, 4‐methoxy, or 4‐ethoxyphenyl)‐4‐(3‐sulfonylazidophenyl)‐2(5H)furanone ( 7a‐c ) and para‐position viz 3‐phenyl‐4‐(4‐sulfonylazidophenyl)‐2(5H)furanone ( 7d ), 3‐(4‐fluoro, or 4‐chlorophenyl)‐4‐(4‐sulfonylazidophenyl)‐2(5H)furanone ( 7e‐f ) of the C–4 phenyl ring, and 4‐(1‐oxido‐4‐pyridyl)‐3‐phenyl‐2(5H)furanone ( 12 ) were designed and synthesized for evaluation as selective cyclooxygenase‐2 (COX‐2) inhibitors. In vitro COX‐1/COX‐2 enzyme inhibition studies showed that 3‐phenyl‐4‐(4‐sulfonylazidophenyl)‐2(5H)furanone ( 7d ) inhibited COX‐1 selectively (COX‐1 IC50 = 0.6659 μM; COX‐2 IC50 > 100 μM) and 3‐(4‐fluorophenyl)‐4‐(4‐sulfonylazidophenyl)‐2(5H)furanone ( 7e ) inhibited both enzymes (COX‐1 IC50 = 0.8494 μM; COX‐2 IC50 = 1.7661 μM). A molecular modeling study was performed where 3‐(4‐fluorophenyl)‐4‐(4‐sulfonylazidophenyl)‐2(5H)furanone ( 7e ) was docked in the active site of murine COX‐2 isozyme, which showed that the sulfonylazido group inserts deep into the 2°‐pocket of COX‐2 where it undergoes both H‐bonding (Gln192, Phe518) and weak electrostatic (Arg513) interactions.  相似文献   

14.
Ternary clusters (NH3)·(H2SO4)·(H2O)n have been widely studied. However, the structures and binding energies of relatively larger cluster (n > 6) remain unclear, which hinders the study of other interesting properties. Ternary clusters of (NH3)·(H2SO4)·(H2O)n, n = 0-14, were investigated using MD simulations and quantum chemical calculations. For n = 1, a proton was transferred from H2SO4 to NH3. For n = 10, both protons of H2SO4 were transferred to NH3 and H2O, respectively. The NH4+ and HSO4 formed a contact ion-pair [NH4+-HSO4] for n = 1-6 and a solvent separated ion-pair [NH4+-H2O-HSO4] for n = 7-9. Therefore, we observed two obvious transitions from neutral to single protonation (from H2SO4 to NH3) to double protonation (from H2SO4 to NH3 and H2O) with increasing n. In general, the structures with single protonation and solvated ion-pair were higher in entropy than those with double protonation and contact ion-pair of single protonation and were thus preferred at higher temperature. As a result, the inversion between single and double protonated clusters was postponed until n = 12 according to the average binding Gibbs free energy at the normal condition. These results can serve as a good start point for studies of the other properties of these clusters and as a model for the solvation of the [H2SO4-NH3] complex in bulk water.  相似文献   

15.
Sulfates and Hydrogensulfates of Erbium: Er(HSO4)3-I, Er(HSO4)3-II, Er(SO4)(HSO4), and Er2(SO4)3 Rod shaped light pink crystals of Er(HSO4)3-I (orthorhombic, Pbca, a = 1195.0(1) pm, b = 949.30(7) pm, c = 1644.3(1) pm) grow from a solution of Er2(SO4)3 in conc. H2SO4 at 250 °C. From slightly diluted solutions (85%) which contain Na2SO4, brick shaped light pink crystals of Er(HSO4)3-II (monoclinic, P21/n, a = 520.00(5) pm, b = 1357.8(1) pm, c = 1233.4(1) pm, β = 92.13(1)°) were obtained at 250 °C and crystals of the same colour of Er(SO4)(HSO4) (monoclinic, P21/n, a = 545.62(6) pm, b = 1075.6(1) pm, c = 1053.1(1) pm, β = 104.58(1)°) at 60 °C. In both hydrogensulfates, Er3+ is surrounded by eight oxygen atoms. In Er(HSO4)3-I layers of HSO4 groups are connected only via hydrogen bridges, while Er(HSO4)3-II consists of a threedimensional polyhedra network. In the crystal structure of Er(SO4)(HSO4) Er3+ is sevenfold coordinated by oxygen atoms, which belong to four SO42–- and three HSO4-tetrahedra, respectively. The anhydrous sulfate, Er2(SO4)3, cannot be prepared from H2SO4 solutions but crystallizes from a NaCl-melt. The coordination number of Er3+ in Er2(SO4)3 (orthorhombic, Pbcn, a = 1270.9(1) pm, b = 913.01(7) pm, c = 921.67(7) pm) is six. The octahedral coordinationpolyhedra are connected via all vertices to the SO42–-tetrahedra.  相似文献   

16.
175, 181Hafnium(IV) was extracted by HDBP in 2-ethylhexanol from 1–10M solutions of HClO4, HCl and HNO3, and 1–8M H2SO4. As with low polar organic phase diluents, the acidity dependence of the distribution ratio of Hf, D, passes through a minimum for HClO4, HCl, and H2SO4 whereas only an increase of D can be observed with increasing HNO3 concentration. From the slope analysis the following complexes were found to be extracted (HDBP=HA): HfA4 at <4M HClO4 and <5M HCl, lg Kextr=9, HfX4(HA)4 (X=ClO 4 , Cl or NO 3 ) at >5M HClO4, >7M HCl and 1–10M HNO3, Hf(SO4)A2(HA)3–4 at <3M H2SO4, and Hf(SO4)2 (HA)4 at >6M H2SO4. Coextraction of sulphate with hafnium from H2SO4 solutions was evidenced in experiments with macro concentrations of Hf(IV) and35SO 4 2− . Part XX: Coll. Czech. Chem. Commun., 40 (1975) 3617.  相似文献   

17.
Ab initio molecular orbital (MO ) calculations for two series of sulfur–oxygen compounds are reported: the S(IV ) system of SO2, H2SO3, HSO, and SO, and the S(VI ) system of SO3, H2SO4, HSO, and SO. Geometries about the sulfur atoms were optimized using the STO -3G* basis set; energies at these geometries were computed by the STO ?3G and 44-31G basis sets both with and without five Gaussian d orbitals on S. The sulfur–oxygen bond lengths and the angles about the central atoms agree fairly well with experiment. The stabilization energy associated with the addition of the d orbitals was found to be a constant amount per bond (ca. 54 and 28 kcal mole?1 in the minimal and extended bases, respectively) in hypervalent compounds. The isomer HSO was predicted to be more stable than SO2(OH)?, but the reverse was true for HSO2(OH) compared to SO(OH)2. The deprotonation energies for the acids and the hydration energies for the oxides also were computed and discussed with reference to experimental data.  相似文献   

18.
The organic ligands 4‐methyl‐1H‐imidazole and 2‐ethyl‐4‐methyl‐1H‐imidazole react with Cu(CF3SO3)2·6H2O to give tetrakis(5‐methyl‐1H‐imidazole‐κN3)­cop­per(II) bis­(tri­fluoro­methane­sulfonate), [Cu(C4H6N2)4](CF3SO3)2, and aqua­tetrakis(2‐ethyl‐5‐methyl‐1H‐imidazole‐κN3)copper(II) bis(tri­ fluoro­methane­sulfonate), [Cu(C6H10N2)4(H2O)](CF3SO3)2. In the former, the Cu atom has an elongated octahedral coordination environment, with four imidazole rings in equatorial positions and two tri­fluoro­methane­sulfonate ions in axial positions. This conformation is similar to those in the analogous complexes tetrakis­(imidazole)­cop­per(II) tri­fluoro­methane­sulfonate and tetrakis(2‐methyl‐1H‐imidazole)­cop­per(II) tri­fluoro­methane­sulfonate. In the second of the title compounds, the ethyl groups block the central Cu atom, and a square‐pyramidal coordination environment is formed around the Cu atom, with the substituted imidazole rings in the basal positions and a water mol­ecule in the axial position.  相似文献   

19.
Iododerivatives of N‐methylcarbazole ( 1 ), N‐phenylcarbazole ( 2 ), N‐benzylcarbazole ( 3 ), 2‐methoxy‐N‐methylcarbazole ( 4 ) and 3‐acetamido‐N‐ethylcarbazole ( 5 ) are synthesised. N‐Iodosuccinimide (NIS) in tetrahydrofurane/H2SO4 (catalyst), a mixture of KIO3 ‐ KI ‐ H2SO4 (catalyst) in ethanol and a mixture of KIO3 ‐ KI in glacial AcOH as iodinating agents have been used and their uses have been compared. The preparation, isolation and characterization of compounds 1a, 1b, 1c, 1d, 2a, 2b, 3a, 3b, 4a, 4b, 4c and 5a are reported (mp, tR, Rf, 1H‐nmr, 13C‐nmr, IR and ms). All of them are described for the first time except 3,6‐diiodo‐N‐phenyl‐carbazole ( 2b ). Semiempirical PM3 calculations have been performed to predict reactivity of N‐substituted carbazoles and their iododerivatives. Theoretical and experimental results are discussed briefly.  相似文献   

20.
Zusammenfassung Bei der Umsetzung von 2-Amino-5-chlorbenzhydrylamin mit SO2Cl2 in Äther entsteht 6-Chlor-2-methyl-4-phenyl-3,4-dihydrochinazolin (5b). Führt man die Reaktion in Pyridin aus, dann erhält man 6-Chlor-4-phenyl-3,4-dihydro-1H-2,1,3-benzothiadiazin-2,2-dioxid (4). Behandelt man 2-Amino-5-chlorbenzophenon sowie die Na-Salze seines N-Acetyl-oder N-Benzoyl-Derivates mit SO2Cl2 und anschließend mit NH3, dann erhält man 6-Chlor-4-phenyl-1H-2,1,3-benzothiadiazin-2,2-dioxid (12), das bei der Hydrierung ebenfalls4 liefert. Die Strukturen der bei diesen Reaktionen als Nebenprodukte auftretenden Verbindungen wurden geklärt.
Cyclic Sulfamides I: Cyclization with sulfuryl chloride
2-Amino-5-chlorobenzhydrylamine reacts with SO2Cl2 in ether to yield 6-chloro-2-methyl-4-phenyl-3.4-dihydroquinazoline (5b) and in pyridine to yield 6-chloro-4-phenyl-3.4-dihydro-1H-2.1.3-benzothiadiazine-2.2-dioxide (4). On treatment with SO2Cl2 followed by reaction with NH3, 2-amino-5-chlorobenzophenone and the Na-salts of its N-acetyl-or N-benzoyl derivative yield 6-chloro-4-phenyl-1H-2.1.3-benzothiadiazine-2.2-dioxide (12). By hydrogenation of the latter compound also4 is obtained. The structures of the by-products of these reactions were elucidated.


Meinem sehr verehrten Lehrer, Herrn o. Prof. Dr.O. Hromatka, in Dankbarkeit mit den besten Wünschen zum 65. Geburtstag gewidmet.

Über den Inhalt dieser Arbeit wurde auszugsweise im Rahmen eines Vortrages vor dem Verein österreichischer Chemiker am 20. Juni 1969 berichtet.  相似文献   

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