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1.
Me3NO activation of the tetrairidium cluster Ir4(CO)12 (1) in presence of the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) furnishes the bpcd-substituted clusters Ir4(CO)10(bpcd) (3) and Ir4(CO)8(bpcd)2 (4) as the minor and major products, respectively. Cluster 3 has been isolated as the sole observable product from the reaction of [Ir4(CO)11Br][Et4N] (2) with bpcd in presence of AgBF4 at room temperature. Both 3 and 4 have been isolated and fully characterized in solution by spectroscopic methods. The solid-state structure of 3 reveals that the ancillary bpcd ligand is bound to a single iridium center, with chelating and bridging bpcd ligands found in the X-ray structure of cluster 4. Cluster 4 is unstable at room temperature and slowly loses CO to afford the hydride-bridged cluster HIr4(CO)4(μ-CO)3(bpcd)[μ-PhP(C6H4)CC(PPh2)C(O)CH2C(O)] (5). Cluster 5 has been fully characterized in solution by IR and NMR spectroscopies, and the C–H bond activation attendant in the ortho metalation step is shown to occur regioselectively at one of the aryl groups associated with the bridging bpcd ligand. The redox properties of clusters 35 have been explored and the electrochemical behavior discussed with respect to extended Hückel MO calculations and related diphosphine-substituted cluster compounds prepared by our groups.  相似文献   

2.
The reaction of the heterometallic vinylidene cluster RuCo2(CO)9(3-2-C=CHPh) with the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) proceeds readily in the presence of Me3NO to furnish the new cluster RuCo2(CO)7(bpcd)(3-2-C=CHPh) as the sole product. This cluster has been isolated by preparative chromatography and characterized in solution by IR spectroscopy. The molecular structure was determined by X-ray diffraction analysis, which has confirmed the chelation of the bpcd ligand to the ruthenium center and the change in the coordination mode exhibited by the vinylidene ligand. RuCo2(CO)7(bpcd)(3-2-C=CHPh) crystallizes in the triclinic space group P , a = 10.5788(9), b = 11.909(1), c = 19.526(2) Å, = 84.491(9)°, = 78.068(8)°, = 63.760(7)°, V = 2158.7(4) Å3, Z = 2, and d calc = 1.581.  相似文献   

3.
One of the products of the reaction of the activated cluster Os3(CO)11(NCMe) with As(p-tol)3 in refluxing nonane has been shown by spectroscopic and X-ray crystallographic methods to be Os3(CO)93-AsC6H4CH3)(μ3-C6H3CH3), which contains a benzyne moiety bonded asymmetrically from one carbon to one osmium via a σ bond and from a second carbon to form a bridge between the remaining two osmium atoms.  相似文献   

4.
用Fe_3(CO)_(12)与亚磷酸三硫代苯酯P(SC_6H_5)_3反应得到标题化合物。P(SC_6H_5)_3以其裂解分子片SC_6H_5和P(SC_6H_5)_2配位。用X-ray衍射技术测定了该化合物的晶体结构, 晶体属正交晶系, 空间群为Pbca, a=1.7422(7), b=1.0634(6), c=2.898(12) nm; V=5.370 nm, z=8, D_c=1.579 g·cm~(-3)。由直接法和差值Fourier合成解出全部非氢原子坐标, 并用全矩阵最小二乘法修正, 最后偏离因子R=0.054, R_w=0.058, 分子结构中心的Fe_2SP折叠环沿S…P线或沿Fe—Fe键折叠的二面角(分别为76.1°和82°)比其它具有中心Fe_2S_2, Fe_2P_2和Fe_2SP折叠环的类似化合物中的相应值小, Fe—Fe键长为0.2572 nm, Fe—S(1)—Fe=68.6°, Fe—P—Fe=70.7°。  相似文献   

5.
Redox condensation of [Ru3H(CO)11]- with Ni(CO)4, in tetrahydrofuran solution, under a nitrogen atmosphere, yields the tetranuclear anion [NiRuH(CO)11)-. Subsequent deprotonation with Bu'OK in acetonitrile solution leads to the formation of the related dianion. Both anions have been characterized by spectroscopic techniques, elemental analysis and single crystal X-ray diffraction. [PPh4][NiRu3H(CO)12] crystallizes in the triclinic space group PI with unit cell dimensionsof a = 11.842(2) Å,b = 12.335(3) Å, c = 13.3080) Å,a = 91.89(2)°, = 93.35(1)°,y = 96.41(2)°, Z = 2, V= 1926.9(7) Å'. The NiRu3, metal core of the molecule defines a distorted tetrahedron with nine terminal and three edge bridging carbonyl groups. The hydrido ligand was located by difference Fourier techniques and was found to bridge the NiRu2 basal triangle at a distance of 0.88(6) A from this plane. Selected average distances and angles are: Ru-Ru = 2.839 Å, Ru-Ni = 2.640 Å, Ru-C, = 1.910 A,Ru-C b = 2.084 Å, Ni-C b = 2.022 Å, Ru-H = 1.77 Å, C-0, = 1.135 Å, C-O b = 1.159 Å, M-C-O, = 176.3°,M-C--O b = 139.3°;other distances are: Ni-C1 = l.758(7) Å, Ni-H= 1.85(7) Å. [NEt4]2[NiRu3(CO)12] crystallizes in the orthorhombic space group Pnma (no. 62) with unit cell dimensions ofa=20.247(5) Å,b = 15.038(4)Å,c = 12.079(3) Å, Z=4, V=3678(2) A'. The molecule contains a tetrahedral NiRu3 core with eight terminal and four edge bridging carbon monoxide groups which bridge the three Ni-Ru and one Ru-Ru bond. Average distances and angles are: Ru -Ru =2.3050A Ru-Ni 2.648 Å, Ru-C t = 1.878 Å, Ru-C b 2.045 Å, Ni-C b = 2.055 Å, C-O t = 1.145 Å, C-01,=1.157 Å, M-C-O,= 176.9°, M-C-O b = 138.6°; other distance is: Ni-C t = 1.754(10) Å,t = terminal,b = bridging.  相似文献   

6.
Treatment of the electronically unsaturated 4-methylquinoline triosmium cluster $[\hbox{Os}_{3}\hbox{(CO)}_{9}(\upmu_3\hbox{-}\upeta^{2}\hbox{-}\hbox{C}_{9}\hbox{H}_{5} \hbox{(4-Me)N})(\upmu\hbox{-H})]$ (1) with tetramethylthiourea in refluxing cyclohexane at 81°C gave $[\hbox{Os}_{3}\hbox{(CO)}_{8}(\upmu\hbox{-}\upeta^{2}\hbox{-C}_{9}\hbox{H}_{5} \hbox{(4-Me)N})(\upeta^2\hbox{-SC}(\hbox{NMe}_2\hbox{NCH}_2\hbox{Me})(\upmu \hbox{-H})_2]$ (2) and $[\hbox{Os}_{3}\hbox{(CO)}_{9}(\upmu\hbox{-}\upeta^{2}\hbox{-C}_{9}\hbox{H}_{5}\hbox{(4-Me)N})(\upeta^1\hbox{-SC}(\hbox{NMe}_2)_2)(\upmu\hbox{-H})]$ (3). In contrast, a similar reaction of the corresponding quinoline compound $[\hbox{Os}_{3}\hbox{(CO)}_{9}(\upmu_{3}\hbox{-}\upeta^{2}\hbox{-C}_{9}\hbox{H}_{6}\hbox{N})(\upmu\hbox{-H})]$ (4) with tetramethylthiourea afforded $[\hbox{Os}_{3}\hbox{(CO)}_{9}(\upmu\hbox{-}\upeta^{2}\hbox{-C}_{9}\hbox{H}_{6}\hbox{N})(\upeta^{1}\hbox{-SC(NMe}_{2})_{2})(\upmu\hbox{-H)}]$ (5) as the only product. Compound 2 contains a cyclometallated tetramethylthiourea ligand which is chelating at the rear osmium atom and a quinolyl ligand coordinated to the Os3 triangle via the nitrogen lone pair and the C(8) atom of the carbocyclic ring. In 3 and 5, the tetramethylthiourea ligand is coordinated at an equatorial site of the osmium atom, which is also bound to the carbon atom of the quinolyl ligand. Compounds 3 and 5 react with PPh3 at room temperature to give the previously reported phosphine substituted products $[\hbox{Os}_{3}\hbox{(CO)}_{9}(\upmu \hbox{-}\upeta^{2}\hbox{-C}_{9}\hbox{H}_{5}\hbox{(4-Me)N)(PPh}_{3})(\upmu\hbox{-H)}]$ (6) and $[\hbox{Os}_{3}\hbox{(CO}_{9}(\upmu \hbox{-}\upeta^{2}\hbox{-C}_{9}\hbox{H}_{6}\hbox{N)(PPh}_{3})(\upmu\hbox{-H)}]$ (7) by the displacement of the tetramethylthiourea ligand.  相似文献   

7.
The complexes Pt(nb)3-n(P-iPr3)n (n=1, 2, nb=bicyclo[2.2.1]hept-2-ene), prepared in situ from Pt(nb)3, are useful reagents for addition of Pt(P-iPr3)n fragments to saturated triruthenium clusters. The complexes Ru3Pt(CO)11(P-iPr3)2 (1), Ru3Pt(-H)(3-3-MeCCHCMe)(CO)9(P-iPr3) (2), Ru3Pt(3-2-PhCCPh)(CO)10(P-iPr3) (3), Ru3Pt(-H)(4-N)(CO)10(P-iPr3) (4) and Ru3Pt(-H)(4-2-NO)(CO)10(P-iPr3) (5) have been prepared in this fashion. All complexes have been characterized spectroscopically and by single crystal X-ray determinations. Clusters 1–3 all have 60 cluster valence electrons (CVE) but exhibit differing metal skeletal geometries. Cluster 1 exhibits a planar-rhomboidal metal skeleton with 5 metal–metal bonds and with minor disorder in the metal atoms. Cluster 2 has a distorted tetrahedral metal arrangement, while cluster 3 has a butterfly framework (butterfly angle=118.93(2)°). Clusters 4 and 5 posseses 62 CVE and spiked triangular metal frameworks. Cluster 4 contains a 4-nitrido ligand, while cluster 5 has a highly unusual 4-2-nitrosyl ligand with a very long nitrosyl N–O distance of 1.366(5) Å.  相似文献   

8.
《Polyhedron》1986,5(3):791-798
The complexes [W(CC6H4Me-4)(CO)2(η-C5H5)] and [Cu(NCMe)4][PF6] in dichloromethane combine to form the salt [Cu&W(CC6H4Me-4)(CO)2(η-C5H5)&2][PF6], but the latter very readily dissociates in solution releasing the tolylmethylidynetungsten compound. The more stable salt [CuW(μ-CC6H4Me-4)(CO)2(NCMe)(PPh3) (η-C5H5)][PF6] is obtained by addition of [W(CC6H4Me-4)(CO)2(η-C5H5)] to a dichloromethane solution of [Cu(NCMe)4][PF6] previously treated with 1 mol equivalent of PPh3. In the presence of additional PPh3, however, no copper-tungsten complex is formed. Several reactions of [CuW(μ-CC6H4Me-4)(CO)2(NCMe)(PPh3)(η-C5H5)][PF6] have been studied, but these led only to release of [W(CC6H4Me-4)(CO)2(η-C5H5)]. The compounds [&CuH(PPh3)&6] and [W(CC6H4Me-4)(CO)2(η-C5H5)] react in toluene at room temperature to give [W(CO)23-CH2C6H4Me-4)(η-C5H5)] and the new cluster compound [CuW23-CC6H4Me-4)(CO)4(PPh3)(η-C5H5)2]. The structure of the latter species has been established by X-ray diffraction. A CuW2 metal triangle [CuW 2.640(2) and 2.610(2), and WW 3.064(1) Å] is asymmetrically capped by a CC6H4Me-4 group [μ3-CCu 2.130(9), μ3-CW 2.035(9) and 2.122(9) Å]. The copper atom is ligated by a PPh3 molecule, and each tungsten by an η5-cyclopentadienyl and two carbonyl groups. The copper atom is weakly coordinated in a semi-bridging manner by two of the CO ligands, one on each tungsten, and is also very weakly bound to a third. The molecule undergoes dynamic behaviour in solution.  相似文献   

9.
In recent years the chemistry of mono- or hetero-binuclear complexes containing metal-S(C) bonding modes is a very active field of research. Many useful applications of this kind of complexes have been exploited, such as industrial catalytic hydrodesulfurization (HDS)1,2 and transition metals mediated organic synthesis3-5. In this paper we report that the reduction and subsequent protonation of hetero-binuclear complex [MnRe(CO)6(-S2CPPri3)] occur with cleavage of metal-metal bond and o…  相似文献   

10.
11.
Microwave heating allows for the high-yield, one-step synthesis of the known triosmium complexes Os3(μ-Br)2(CO)10 (1), Os3(μ-I)2(CO)10 (2), and Os3(μ-H)(μ-OR)(CO)10 with R = methyl (3), ethyl (4), isopropyl (5), n-butyl (6), and phenyl (7). In addition, the new clusters Os3(μ-H)(μ-OR)(CO)10 with R = n-propyl (8), sec-butyl (9), isobutyl (10), and tert-butyl (11) are synthesized in a microwave reactor. The preparation of these complexes is easily accomplished without the need to first prepare an activated derivative of Os3(CO)12, and without the need to exclude air from the reaction vessel. The syntheses of complexes 1 and 2 are carried out in less than 15 min by heating stoichiometric mixtures of Os3(CO)12 and the appropriate halogen in cyclohexane. Clusters 36 and 810 are prepared by the microwave irradiation of Os3(CO)12 in neat alcohols, while clusters 7 and 11 are prepared from mixtures of Os3(CO)12, alcohol and 1,2-dichlorobenzene. Structural characterization of clusters 2, 4, and 5 was carried out by X-ray crystallographic analysis. High resolution X-ray crystal structures of two other oxidative addition products, Os3(CO)12I2 (12) and Os3(μ-H)(μ-O2CC6H5)(CO)10 (13), are also presented.  相似文献   

12.
The reactivity of the bidentate ligand 2,3-bis(diphenylphosphino)-N-phenylmaleimide (bppm) with the tetrahedrane cluster PhCCo3(CO)9 under thermolysis and ETC conditions has been studied and found to ultimately give Co3(CO)6221-C(Ph) ${\text{C}}{\text{ = }}{\text{ = }}{\text{C(PPh}}_{\text{2}} {\text{)C(O)NPhC}}$ (O)](μ2-PPh2) as the final product. The intermediate cluster compound PhCCo3(CO)7(bppm), which was observed by IR and 31P NMR spectroscopies, readily and rapidly transforms into the product cluster under the reactions conditions. The solid-state structure of Co3(CO)6221-C(Ph)fptt(O)](μ2-PPh$_{2})$ was unequivocally determined by X-ray crystallography. Co3(CO)62, η2, η1-C(Ph)Õ(O)](μ2-PPh2) crystallizes in the monoclinic space group P2(1)/n, a = 11.825(5) Å, b = 31.20(1) Å, c = 11.831(5) Å, β = 108.720(7)°, V = 4134(7) Å3, Z = 4, d calc = 1.567 Mg/m3; R = 0.0350, R w = 0.0817 for 4747 observed reflections with I > 2σ(I). The X-ray structure confirms the coupling of the benzylidyne ligand with the bppm ligand in Co3(CO)6221-C(Ph)Õ(O)](μ2-PPh2). The course of the thermolysis reaction is identical to those reactions carried out with the related diphosphine ligands bma and bpcd. The utility of electron-transfer catalysis (ETC) in the preparation of PhCCo3(CO)7(bppm) is discussed relative to the reduction potential of the bppm ligand and the tricobalt cluster PhCCo3(CO)9.  相似文献   

13.
The reactions of the heterometallic complexes (-H)Os3(-O2CC5H4FeCp)(CO)10 (1) and Fe{(-O2CC5H4)(-H)Os3(CO)10}2 (2) with CF3COOH, CF3SO3H, and AcCl were studied. The reaction of 1 with CF3COOH involves interaction with the Cp ligands, protonation of the O atom of the bridging carboxylate group, and oxidative degradation of the complex. At low concentrations, CF3SO3H protonates the O atom of the bridging carboxylate group, while at high concentrations, degradation of the complex takes place. The reaction of complex 2with either CF3COOH or low concentrations of CF3SO3H results in successive elimination of two [(-H)Os3(CO)10] cluster fragments due to protonation of the O atoms of the carboxylate groups. In the case of high CF3SO3H concentrations, the Os—Os bonds of both cluster fragments of 2 are also protonated to give the [Fe{(-O2CC5H4)(-H)2Os3(CO)10}2]2+ dication. The Friedel—Crafts acylation of 1 takes place only when a large excess of AcCl and AlCl3 is used to give two new complexes, (-H)Os3(-O2CC5H4FeC5H4C(O)CH3)(CO)10 and (-H)Os3(-O2CC5H3C(O)CH3FeCp)(CO)10 in a 2 : 1 ratio.  相似文献   

14.
Thecloso octahedral cluster Ru4(CO)114-PPh)(μ4-S)1 and selenium and tellurium analogues, the first examples of unsaturated ruthenium clusters with a planar metal core and different main group 15 and 16 atoms have been synthesized fromnido Ru4(CO)133-PPh). An X-ray analysis of1 and Ru4(CO)104-PPh)(μ4-Se)(PEt3)2a has confirmed thetrans disposition of phosphorus and group 16 main group fragments.  相似文献   

15.
The reaction of the methylidyne-bridged cluster HRu3(CO)10(μ-COMe) (1) with the diphosphine ligand 4,5-bis(diphenylphosphino)-4-cyclopenten-1,3-dione (bpcd) and Me3NO furnishes HRu3(CO)8(μ-COMe)(bpcd) (2) and HRu3(CO)8(Ph2PH)[μ-PPh2CCC(O)CH2C(O)] (3) as the major and minor products, respectively. The 1H and 31P NMR data indicate that the bpcd ligand in 2 is chelated to one of the ruthenium atoms that is bridged by the hydride and methylidyne ligands. Thermolysis of 2 is accompanied by P-Ph bond cleavage and elimination of benzene to yield Ru3(CO)73-COMe)[μ-P(Ph)CC(PPh2)C(O)CH2C(O)] (4). Compound 4 consists of a triangular ruthenium core that is face-capped by μ3-COMe methylidyne and μ-P(Ph)CC(PPh2)C(O)CH2C(O) phosphido ligands. The kinetics for the conversion of 2 → 4 have been measured in toluene solvent over the temperature range 320-343 K, and based on the observed activation parameters and the inhibitory effect of added CO on the reaction, a rate-limiting step involving a dissociative loss of CO is supported. Heating 4 in the presence of H2 afforded the phosphinidene-capped cluster H3Ru3(CO)73-PPh)[μ-CC(PPh2)C(O)CH2C(O)] (5). Crystallographic analysis of 5 has confirmed the loss of the methylidyne moiety and the cleavage of the phosphido PhP-C(dione) bond, and the presence of three edge-bridging hydrides is supported by 1H NMR spectroscopy. The reaction of 4 with added PPh3 and PMe3 has been investigated; the uptake of a single phosphine ligand occurs regiospecifically at one of the phosphido-bound ruthenium centers to give Ru3(CO)6L(μ3-COMe)[μ-P(Ph)CC(PPh2)C(O)CH2C(O)] (PPh3, 6; PMe3, 7). Compound 6 contains 48e- and exhibits a structural motif similar to that found in 4. Compound 7 readily adds a second PMe3 ligand to yield the bis-substituted cluster Ru3(CO)6(PMe3)22-COMe)[μ-P(Ph)CC(PPh2)C(O)CH2C(O)] (8). The solid-state structure of 8 confirms the loss of two ruthenium-ruthenium bonds and the conversion of the original face-capping μ3-COMe ligand to a μ2-COMe moiety that tethers two non-bonding ruthenium centers. The two PMe3 ligands in 8 coordinate to the same ruthenium center, and the 9e- P(Ph)CC(PPh2)C(O)CH2C(O) ligand binds all three ruthenium atoms through the phosphine, phosphido, alkene, and carbonyl moieties. Near-UV irradiation of 8 leads to loss of CO and polyhedral contraction of the triruthenium frame to yield the 48e- cluster Ru3(CO)5(PMe3)23-COMe)[μ-P(Ph)CC(PPh2)C(O)CH2C(O)] (9).  相似文献   

16.
By X-ray diffraction study the structure of two new carbonyl cluster complexes of the composition [Fe44-Q)(μ4-AsMe)(CO)11], where Q = Se or Te, is determined. The structures are molecular, and the seleniumcontaining cluster complex crystallizes in the form of a solvate with toluene.  相似文献   

17.
Thermolysis of [Ru3(CO)12] in cyclohexene for 24 h affords the complexes [Ru(CO)34-C6H8)] (1), [Ru3H2(CO)92121-C6H8)] (2), [Ru4(CO)124-C6H8)] (3) [Ru4(CO)94-C6H8)(η6-C6H6)] (4a and 4b, two isomers) and [Ru5(CO)1242-C6H8)(η4-C6H8)] (5), where 1, 3, 4a and 4b have been previously characterised as products of the thermolysis of [Ru3(CO)12] with cyclohexa-1,3-diene. The molecular structures of the new clusters 2 and 5 were determined by single-crystal X-ray crystallography, showing that two conformational polymorphs of 5 exist in the solid state, differing in the orientation of the cyclohexa-1,3-diene ligand on a ruthenium vertex.  相似文献   

18.
The reaction of PtRu5(CO)166-C),1 with 3-hexyne in the presence of UV irradiation produced two new electron-rich platinum-ruthenium cluster complexes PtRu5(CO)13(μ-EtC2Et)(μ3-EtC2Et)(μ5-C),2 (20% yield) and Pt2Ru6(CO)17(μ-η5-Et4C5)(μ3-EtC2Et) (μ6-C),3 (7% yield). Both compounds were characterized by single-crystal X-ray diffraction analyses. Compound2 contains of a platinum capped square pyramidal cluster of five ruthenium atoms with the carbido ligand located in the center of the square pyramid. A EtC2Et ligand bridges one of the PtRu2 triangles and the Ru-Pt bond between the apical ruthenium atom and the platinum cap. The structure of compound3 consists of an octahedral PtRu5 cluster with an interstitial carbido ligand and a platinum atom capping one of the PtRu2 triangles. There is an additional Ru(CO)2 group extending from the platinum atom in the PtRu5 cluster that contains a metallated tetraethylcyclopentadienyl ligand that bridges to the platinum capping group. There is also a EtC2Et ligand bridging one of the PtRu2 triangular faces to the capping platinum atom. Compounds2 and3 both contain two valence electrons more than the number predicted by conventional electron counting theories, and both also possess unusually long metal-metal bonds that may be related to these anomalous electron configurations. Crystal data for2, space group Pna21,a=19.951(3) Å,b=9.905(2) Å,c=17.180(2) Å,Z=2, 1844 reflections,R=0.036; for3, space group Pna21,α=13.339(1) Å,b=14.671(2) Å,c=11.748(2) Å, α=100.18(1)°, β=95.79(1)°, γ=83.671(9)°,Z=2, 3127 reflections,R=0.026.  相似文献   

19.
Rh2(μ-SC6H5)2(CO)4的合成和晶体结构   总被引:2,自引:0,他引:2  
一种路易斯碱,例如膦(PR3)或异氰化物(CNR)加到双核或多核络合物中,会导致低核物种的形成,这就伴随有金属一金属键的断裂[1].这样的例子很多,如我们曾用F33(CO)12与P(SC6H5)3反应,分离出三个不同的两核铁数合物[2].现在我们报导另一个例子:用Rh4(CO)12与P(SC6H小反应,同样也得到一个两核物种WhZ(P-SC6H巾(C)4.该化合物首先由B0ltoll*等人用WhZ(CO)ZC12与苯硫酚C6H。SH反应得到,但有关它的X-rar晶体结构的测定还未见报导·与之相似的化合物Rh。(p-SC。H。F)。门O)。的结构已由ClaverN…  相似文献   

20.
The Os3(-H)2(CO)7(-C6H4){3-Ph2PCH2P(C6H4)Ph} complex, which was isolated from the products of thermolysis of Os3(CO)10(-dppm) (dppm is Ph2PCH2PPh2) in toluene, was characterized by X-ray diffraction analysis. Protonation of the resulting complex with trifluoroacetic acid afforded the cationic complex [Os3(-H)3(CO)7(-C6H4){3-Ph2PCH2P(C6H4)Ph}]+.  相似文献   

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