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1.
The reaction of dibenzenediselenide, (SePh)2, with mercury in refluxing xylene gives bis(benzeneselenolato)mercury(II), [Hg(SePh)2], in a good yield. (nBu4N)[Hg(SePh)3] is obtained by the reaction of [Hg(SePh)2] with a solution of [SePh] and (nBu4N)Br in ethanol. The solid state structures of both compounds have been determined by X-ray diffraction. The mercury atom in [Hg(SePh)2] (space group C2, a = 7.428(2), b = 5.670(1), c = 14.796(4) Å, β = 103.60(1)°) is linearly co-ordinated by two selenium atoms (Hg–Se = 2.471(2) Å, Se–Hg–Se = 178.0(3)°). Additional weak interactions between the metal and selenium atoms of neighbouring molecules (Hg…Se = 3.4–3.6 Å) associate the [Hg(SePh)2] units to layers. The crystal structure of (nBu4N)[Hg(SePh)3] (space group P21/c, a = 9.741(1), b = 17.334(1), c = 21.785(1) Å, β = 95.27(5)°) consists of discrete complex anions and (nBu4N)+ counter ions. The coordination geometry of mercury is distorted trigonal-planar with Hg–Se distances ranging between 2.5 and 2.6 Å.  相似文献   

2.
The compounds [Hg2(μ—SePh)2(SePh)2(PPh3)2] ( I ) and [Hg3Br3(μ—SePh)3] · 2 DMSO ( II ) are formed by reactions of [Hg(SePh)2] with PPh3 in THF( I ) or with HgBr2 in DMSO ( II ) at room temperature. X—ray crystallography reveals that the cluster I consists of a distorted square built by each two Hg and Se atoms. The Hg atoms have almost tetrahedral co‐ordination environments formed by selenium atoms of two (μ‐SePh) ligands and Se and P atoms of terminal SePh and PPh3 ligands. The compound II is a six‐membered ring with alternating Hg and Se atoms in the chair conformation. Two DMSO molecules occupy positions below and above the [Hg3Se3] ring with the oxygen atoms directed to the centre of the ring.  相似文献   

3.
Synthesis and Structures of the Selenolato-Bridged Mercury Clusters [Hg6(SePh)12(P t Bu3)2] and (HP t Bu3)2[Hg6(SePh)14] The reaction of HgCl2 with PtBu3 and PhSeSiMe3 yields [Hg6(SePh)12(PtBu3)2] ( 1 ) and (HPtBu3)2[Hg6(SePh)14] ( 2 ). X-ray structural analysis of the compounds shows them to have similar Hg–Se cages with distorted tetrahedral coordination around mercury. The cages are built up from edge- and vertex-sharing distorted tetrahedra.  相似文献   

4.
Reaction of lithium phenylselenothiolate, generated in situ from the reductive cleavage of PhSe‐SiMe3 with alkyl lithium reagents and insertion of elemental sulfur, with triphenylphosphine solubilized CuCl affords the molecular cluster complex [Cu20Se43‐SePh)12(PPh3)6] ( 1 ). The analogous reaction with AgCl yields the extended structure [Ag(SePh)] ( 2 ) in which an infinite layer of AgI atoms is capped on either side by μ4‐SePh ligands. 1: space group P¯1, a = 17.9510(6), b = 18.1712(7), c = 31.4311(11) Å, a = 78.098(2), β = 82.905(2), γ = 70.012(2)°. 2: space group C2/c, a = 5.8762(6), b = 7.2989(7), c = 29.124(2) Å, β = 95.790(3)°.  相似文献   

5.
Syntheses and Crystal Structures of new Selenido‐ and Selenolato‐bridged Copper Clusters: [Cu38Se13(SePh)12(dppb)6] (1), [Cu(dppp)2][Cu25Se4(SePh)18(dppp)2] (2), [Cu36Se5(SePh)26(dppa)4] (3), [Cu58Se16(SePh)24(dppa)6] (4), and [Cu3(SeMes)3(dppm)] (5) The reactions of copper(I) chloride or copper(I) acetate with monodentate phosphine ligands (PR3; R = organic group) and Se(SiMe3)2 have already lead to the formation of CuSe clusters with up to 146 copper and 73 selenium atoms. If the starting materials and the bidentate phosphine ligands (Ph2P–(CH2)n–PPh2, n = 1: dppm, n = 3: dppp, n = 4: dppb; Ph2P–C≡C–PPh2: dppa) and silylated chalcogen derivates are changed (RSeSiMe3; R = Ph, Mes) a series of new CuSe clusters can be synthesized. From single crystal X‐ray structure analysis one can characterise [Cu38Se13(SePh)12(dppb)6] ( 1 ), [Cu(dppp)2] · [Cu25Se4(SePh)18(dppp)2] ( 2 ), [Cu36Se5(SePh)26(dppa)4] ( 3 ), [Cu58Se16(SePh)24(dppa)6] ( 4 ) and [Cu3(SeMes)3(dppm)] ( 5 ). In this new class of CuSe clusters, compounds 1 and 4 possess a spherical cluster skeleton, wheras 2 and 3 have a layered cluster core.  相似文献   

6.
Analytical studies on the thermolysis products from [Cd10Se4(SePh)12(PnPr3)4] are reported leading to the identification of the doubly negatively charged species [Cd17Se4(SePh)28]2−. Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) has been successfully applied to analyse the composition of a polycrystalline precipitate after treatment with SePh in tetrahydrofuran (THF). Presumably, SePhreacts with the insoluble (polymeric) cluster product as a charging ligand leading to dissolved monomeric units of the cluster anion [Cd17Se4(SePh)28]2−. This cluster anion could also be crystallized from solutions as [Na(thf)218-crown-6][Cd17Se4(SePh)28] and [Na(dme)3]2[Cd17Se4(SePh)28]. The experimental results promise a wider applicability of the charged ligand exchange method for the electrospray mass spectrometric characterization of neutral clusters and to obtain intensive monodisperse cluster ion beams for further gas-phase studies. Dedicated to Prof. Dieter Fenske on the occasion of his 65th birthday.  相似文献   

7.
The reaction of [(3,5‐Me2–C5H3N)2Zn(SeSiMe3)2] with a solution of Cd(OAc)2, Se(Ph)SiMe3 and PPr3 at low temperature was used to prepare single crystals of ternary group 12–12′‐16 nanoclusters with the composition [Zn1.8Cd8.2Se4(SePh)12(PPr3)4]. A ligand exchange reaction using Na[SePh] was performed to displace the neutral PPr3 ligands. The resulting clusters were probed using electrospray ionization mass spectrometry to determine the number of zinc and cadmium atoms in the cluster and compared to the all cadmium cluster [Cd10Se4(SePh)12(PPr3)4]. The dianionic clusters [ZnxCd10–xSe4(SePh)14]2– where x = 0, 1, 2 were assigned in the mass spectra, revealing that the clusters exhibit elemental distributions that are quite narrow in these experiments.  相似文献   

8.
The title compound [K([2,2,2]crypt)]12[Sn9]2[Sn9HgSn9] has been obtained by reaction of elemental mercury with the binary phase K4Sn9 in ethylenediamine after addition of [2,2,2]crypt and layering with toluene. The X‐ray single crystal analysis shows that the compound consists of two isolated Sn9 clusters and two Sn9 clusters connected by a mercury atom.  相似文献   

9.
Synthesis of Mixed Chalcogenido‐Bridged Dirhenium Complexes of the Type Re2(μ‐ER)(μ‐E′R′)(CO)8 (E, E′ = S, Se, Te; R, R′ = org. Residue) Hydrido sulfido bridged complexes Re2(μ‐H)(μ‐SR)(CO)8 (R = Ph, naph, Cy) react with the base DBU to give the salts [DBUH][Re2(μ‐SR)(CO)8]. Upon addition of electrophiles R′E′Br (E′R = SPh, SePh, TePh) to the in situ prepared salts mixed chalcogenido bridged complexes Re2(μ‐SR)(μ‐E′R′)(CO)8 were formed. The structures of the new compounds Re2(μ‐SCy)(μ‐SePh)(CO)8 and Re2(μ‐Snaph)(μ‐TePh)(CO)8 were determined by single crystal X‐ray analyses. For the preparation of analogous selenido tellurido bridged complexes Re2(μ‐SePh)(μ‐TeR)(CO)8 the novel hydrido selenido bridged complex Re2(μ‐H)(μ‐SePh)(CO)8 was prepared from Re2(CO)8(NCMe)2 and PhSeH. Its structure was determined by single crystal X‐ray analysis. Subsequent deprotonation with DBU gave in situ [DBUH][Re2(μ‐SePh)(CO)8] which upon addition of RTeBr (R = Ph, Bun, But) formed the desired complexes Re2(μ‐SePh)(μ‐TeR)(CO)8. The reaction with ButTeBr also yielded the novel spirocyclic complex (μ4‐Te){Re2(μ‐SePh)(CO)8}2 in low amounts. It was identified by single crystal X‐ray analysis. Re2(μ‐SePh)(μ‐TeBut)(CO)8 is oxidised in chloroform in the presence of air to give the novel complex (μ‐Te–Te‐μ){Re2(μ‐SePh)(CO)8}2. All mixed chalcogenido bridged dirhenium complexes were proved to be dynamic in solution by 13C NMR spectroscopy. The dynamic behaviour is based on the fast and permanent inversion of the sulfido and selenido bridges. The tellurido bridges are rigid on the time scale of 13C NMR spectroscopy.  相似文献   

10.
The accessibility of triads with deltahedral Zintl clusters in analogy to fullerene–linker–fullerene triads is another example for the close relationship between fullerenes and Zintl clusters. The compound {[K(2.2.2‐crypt)]4[RGe9‐CHCH CHCH‐Ge9R]}(toluene)2 (R=(2Z,4E)‐7‐amino‐5‐aza‐hepta‐2,4‐dien‐2‐yl), containing two deltahedral [Ge9] clusters linked by a conjugated (1Z,3Z)‐buta‐1,3‐dien‐1,4‐diyl bridge, was synthesized through the reaction of 1,4‐bis(trimethylsilyl)butadiyne with K4Ge9 in ethylenediamine and crystallized after the addition of 2.2.2‐cryptand and toluene. The compound was characterized by single‐crystal structure analysis as well asNMR and IR spectroscopy.  相似文献   

11.
. The complex Hg4(L2)2(NO3)4 ( 1 ) (L2 = morpholin‐4‐ylpyridin‐2‐ylmethyleneamine) has been synthesized and characterized by CHN analysis, IR, and UV/Vis spectroscopy. The crystal structure of 1 was determined using single‐crystal X‐ray diffraction. The crystal structure of 1 contains four mercury atoms, four nitrate anions (two terminal and two bridge ones) and two L2 ligand molecules. A chair shape, six‐membered ring is formed with the sequence OHgHgOHgHg built from Hg–Hg dumbbells and oxygen atoms from the nitrate co‐ligands. In the crystal structure, the asymmetric unit of the compound is built up by one‐half of the molecule. It contains the Hg22+ moiety with a mercury–mercury bonded core, in which one diimine ligand is coordinated to one of the mercury atoms. The nitrate anions act as anisobidentate and bidentate ligands.  相似文献   

12.
The accessibility of triads with deltahedral Zintl clusters in analogy to fullerene–linker–fullerene triads is another example for the close relationship between fullerenes and Zintl clusters. The compound {[K(2.2.2‐crypt)]4[RGe9‐CH?CH? CH?CH‐Ge9R]}(toluene)2 (R=(2Z,4E)‐7‐amino‐5‐aza‐hepta‐2,4‐dien‐2‐yl), containing two deltahedral [Ge9] clusters linked by a conjugated (1Z,3Z)‐buta‐1,3‐dien‐1,4‐diyl bridge, was synthesized through the reaction of 1,4‐bis(trimethylsilyl)butadiyne with K4Ge9 in ethylenediamine and crystallized after the addition of 2.2.2‐cryptand and toluene. The compound was characterized by single‐crystal structure analysis as well asNMR and IR spectroscopy.  相似文献   

13.
We report the time‐resolved supramolecular assembly of a series of nanoscale polyoxometalate clusters (from the same one‐pot reaction) of the form: [H(10+m)Ag18Cl(Te3W38O134)2]n, where n=1 and m=0 for compound 1 (after 4 days), n=2 and m=3 for compound 2 (after 10 days), and n=∞ and m=5 for compound 3 (after 14 days). The reaction is based upon the self‐organization of two {Te3W38} units around a single chloride template and the formation of a {Ag12} cluster, giving a {Ag12}‐in‐{W76} cluster‐in‐cluster in compound 1 , which further aggregates to cluster compounds 2 and 3 by supramolecular Ag‐POM interactions. The proposed mechanism for the formation of the clusters has been studied by ESI‐MS. Further, control experiments demonstrate the crucial role that TeO32?, Cl?, and Ag+ play in the self‐assembly of compounds 1 – 3 .  相似文献   

14.
The formation of crystalline CdSe particles in the thermal degradation of Cd(SePh)2·TMEDA (TMEDA = tetramethylethylenediamine) as a single‐source‐precursor was investigated by in‐situ powder X‐ray diffraction. It was shown that the primary grains were formed in the cubic zinc blende modification. After an increase in particle size by further annealing a phase transition to the thermodynamically favored hexagonal wurtzite type was detected. This behaviour indicates that, according to Ostwald's rule, the primary grains consist of the less stable polymorph due to the lower activation barrier of its formation. When the volume energy of the particles gets dominant over the surface energy, the metastable form is transformed and the system adopts the modification of lowest energy.  相似文献   

15.
In this article, we present a facile, direct, synthetic approach of preparing monodisperse [Au25(SePh)18]-nanoclusters in high yield. In this synthetic approach, two-phase Brust-Schiffrin method is used. Both PhSeH and NaBH4 should be added drop-wise to the solution of Au(III) at the same time. The formula and molecular purity of [Au25(SePh)18]-TOA+ clusters are characterized by MALDI-TOF mass spectrometry, NMR and TGA analysis. Furthermore, some critical parameters to obtain pure [Au25(SePh)18]-TOA+ are identified, including the NaBH4-to-Au ratio, the selenolate-to-Au ratio and the temperature. The facile, direct, high yield synthetic method can be widely applied in the theoretical research of Au clusters protected by selenol.  相似文献   

16.
The crystal structure of the known compound HgSnP14 (HgPbP14‐type, Pnma, Z = 4) was refined from single‐crystal X‐ray diffractometer data to a residual of R = 0.067 for 1470 structure factors and 83 variable parameters. This polyphosphide has a smaller cell volume than the isotypic compound CdSnP14. For that reason it had been suggested earlier that the mercury atoms in HgSnP14 will show a tendency for linear P—Hg—P coordination. This is not supported by the present structure refinement, which shows a distorted tetrahedral phosphorus coordination for the mercury atoms, very similar to that of the cadmium atoms in CdSnP14. A brief literature survey shows that quite generally the mercury atoms have a smaller volume requirement than the cadmium atoms in intermetallics and more or less covalent compositions, in contrast to more ionic compounds, where the inverse relationship is observed. Chemical bonding in HgSnP14 can be rationalized on the basis of the Zintl‐Klemm concept, resulting in the formula Hg+2Sn+2(P14)—4. Accordingly, the environment of the tin atoms shows the lone pair effect. Reactions of the elemental components aiming for the isotypic compounds CuSnP14, CuPbP14, AgSnP14, AgPbP14, AuSnP14, and AuPbP14 resulted in microcrystalline samples. The fibrous habit and the energy dispersive X‐ray fluorescence analyses of the products indicate the formation of these polyphosphides. Only for the gold‐tin compound was it possible to isolate a single crystal suitable for a structure refinement, which confirmed its HgPbP14‐type structure: a = 1259.5(3) pm, b = 982.0(2) pm, c = 1056.2(3) pm, R = 0.046 for 1520 F values and 87 variables. The gold position was found with a lower occupancy, thus resulting in the two possible extreme formulas Au0.852(4)SnP14 and Au0.64(1)Sn1.36(1)P14, depending of whether vacancies or a mixed Au/Sn occupancy is assumed for this position. An analysis of interatomic distances suggests the latter formula to be correct with tetravalent tin on the gold sites corresponding to the formula [(Au+1)0.64(1)(Sn+4)0.36(1)]+2.08(3)[SnP14]—2.  相似文献   

17.
The structure of lanthanum tetrazinc, LaZn4, has been determined from single‐crystal X‐ray diffraction data for the first time, approximately 70 years after its discovery. The compound exhibits a new structure type in the space group Cmcm, with one La atom and two Zn atoms occupying sites with m2m symmetry, and one Zn atom occupying a site with 2.. symmetry. The structure is closely related to the BaAl4, La3Al11, BaNi2Si2 and CaCu5 structure types, which can be presented as close‐packed arrangements of 18‐vertex clusters, in this case LaZn18. The kindred structure types contain related 18‐vertex clusters around atoms of the rare earth or alkaline earth metal.  相似文献   

18.
Gas‐phase clusters are deemed to be σ‐aromatic when they satisfy the 4n+2 rule of aromaticity for delocalized σ electrons and fulfill other requirements known for aromatic systems. While the range of n values was shown to be quite broad when applied to short‐lived clusters found in molecular‐beam experiments, stability of all‐metal cluster‐like fragments isolated in condensed phase was previously shown to be mainly ascribed to two electrons (n=0). In this work, the applicability of this concept is extended towards solid‐state compounds by demonstrating a unique example of a storable compound, which was isolated as a stable [K([2.2.2]crypt)]+ salt, featuring a [Au2Sb16]4? cluster core possessing two all‐metal aromatic AuSb4 fragments with six delocalized σ electrons each (n=1). This discovery pushes the boundaries of the original idea of Kekulé and firmly establishes the usefulness of the σ‐aromaticity concept as a general idea for both small clusters and solid‐state compounds.  相似文献   

19.
The structures of the title compound, C20H24N2O4S2, and its mercury(II) dichloride complex, dichloro{20‐di­cyano­methyl­ene‐5,8,11,14‐tetraoxa‐2,17‐di­thia­bi­cyclo­[16.4.1]­tricosa‐1(23),18,­21‐tri­ene‐κ4OS17}mercury(II), [HgCl2(C20­H24­N2­O4­S2)], have been determined by X‐ray crystallographic analyses. The mercury(II) dichloride complex has two independent mol­ecules of [HgCl2(C20H24N2O4S2)] in the lattice. The mercury(II) ion has pentagonal bipyramidal coordination which involves one S atom, four O atoms and two Cl? ions.  相似文献   

20.
Zincselenide- and Zinctellurideclusters with Phenylselenolate- and Phenyltellurolateligands. The Crystal Structures of [NEt4]2[Zn4Cl4(SePh)6], [NEt4]2[Zn8Cl4Se(SePh)12], [Zn8Se(SePh)14(PnPr3)2], [HPnPr2R]2[Zn8Cl4Te(TePh)12] (R = nPr, Ph), and [Zn10Te4(TePh)12(PR3)2] (R = nPr, Ph) In the prescence of NEt4Cl ZnCl2 reacts with PhSeSiMe3 or a mixture of PhSeSiMe3/Se(SiMe3)2 to form the ionic complexes [NEt4]2[Zn4Cl4(SePh)6] 1 or [NEt4]2[Zn8Cl4Se(SePh)12] 2 respectively. The use of PnPr3 instead of the quarternary ammonia salt leads in toluene to the formation of crystalline [Zn8Se(SePh)14(PnPr3)2] 3 . Reactions of ZnCl2 with PhTeSiMe3 and tertiary phosphines result in acetone in crystallisation of the ionic clusters [HPnPr2R]2[Zn8Cl4Te(TePh)12] (R = nPr 4 , Ph 5 ) and in THF of the uncharged [Zn10Te4(TePh)12(PR3)2] (R = nPr 6 , Ph 7 ). The structures of 1–7 were obtained by X-ray single crystal structure. ( 1 : space group P21/n (No. 14), Z = 4, a = 1212,4(2) pm, b = 3726,1(8) pm, c = 1379,4(3) pm β = 99,83(3)°; 2 space group P21/c (Nr. 14), Z = 4, a = 3848,6(8) pm, b = 1784,9(4) pm, c = 3432,0(7) pm, β = 97,78(3)°; 3 : space group Pnn2 (No. 34), Z = 2, a = 2027,8(4) pm, b = 2162,3(4) pm, c = 1668,5(3) pm; 4 : space group P21/c (No. 14), Z = 4, a = 1899,8(4) pm, b = 2227,0(5) pm, c = 2939,0(6) pm, β = 101,35(3)°; 5 : space group space group P21/n (No. 14), Z = 4, a = 2231,0(5) pm, b = 1919,9(4) pm, c = 3139,5(6) pm, β = 109,97(4)°; 6 : space group I41/a (No. 88), Z = 4, a = b = 2566,0(4) pm, c = 2130,1(4) pm; 7 : space group P1¯ (No. 2), Z = 2, a = 2068,4(4) pm, b = 2187,8(4) pm, c = 2351,5(5) pm, α = 70,36°, β = 84,62°, γ( = 63,63°)  相似文献   

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