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Complete exchange : [M6X12] type cluster compounds with an octahedral M6 metal atom arrangement, which is completely surrounded by alcoholato ligands, were unknown until now. The first representatives are prepared containing a [Nb6(OR)12]4+ unit (R=CH3 or C2H5). They are accessible at elevated temperatures from strongly basic alcoholate solutions of [Nb6Cl12]2+‐containing precursors. C gray, H white, K turquoise, Nb blue, O red.

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Specific molecular recognition of γ-cyclodextrin (γ-CD) by the cationic hexanuclear niobium [Nb6Cl12(H2O)6]2+ cluster complex in aqueous solutions results in a 1:1 supramolecular assembly {[Nb6Cl12(H2O)6]@γ-CD}2+. NMR spectroscopy, isothermal titration calorimetry (ITC), and ESI-MS were used to study the interaction between the inorganic cluster and the organic macrocycle. Such molecular association affects the biological activity of [Nb6Cl12(H2O)6]2+, decreasing its cytotoxicity despite enhanced cellular uptake. The 1:1 stoichiometry is maintained in solution over a large window of the reagents’ ratio, but crystallization by slow evaporation produces a 1:2 host–guest complex [Nb6Cl12(H2O)6@(γ-CD)2]Cl2 ⋅ 20 H2O featuring the cluster encapsulated between two molecules of γ-CD. The 1:2 complex was characterized by XRD, elemental analysis, IR spectroscopy, and thermogravimetric analysis (TGA). Quantum chemical calculations were performed to model host–guest interaction.  相似文献   

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Alkoxo Compounds of Iron(III): Syntheses and Characterization of [Fe2(OtBu)6], [Fe2Cl2(OtBu)4], [Fe2Cl4(OtBu)2] and [N(nBu)4]2[Fe6OCl6(OMe)12] The reaction of iron(III)chloride in diethylether with sodium tert‐butylat yielded the homoleptic dimeric tert‐‐butoxide Fe2(OtBu)6 ( 1 ). The chloro‐derivatives [Fe2Cl2(OtBu)4] ( 2 ), and [Fe2Cl4(OtBu)2] ( 3 ) could be synthesized by ligand exchange between 1 and iron(III)chloride. Each of the molecules 1 , 2 , and 3 consists of two edge‐sharing tetrahedrons, with two tert‐butoxo‐groups as μ2‐bridging ligands. For the synthesis of the alkoxides 1 , 2 , and 3 diethylether plays an important role. In the first step the dietherate of iron(III)chloride FeCl3(OEt2)2 ( 4 ) is formed. The reaction of iron(III)chloride with tetrabutylammonium methoxide in methanol results in the formation of a tetrabutylammonium methoxo‐chloro‐oxo‐hexairon cluster [N(nBu)4]2[Fe6OCl6(OMe)12] ( 5 ). Crystal structure data: 1 , triclinic, P1¯, a = 9.882(2) Å, b = 10.523(2) Å, c = 15.972(3) Å, α = 73.986(4)°, β = 88.713(4)°, γ = 87.145(4)°, V = 1594.4(5) Å3, Z = 2, dc = 1.146 gcm—1, R1 = 0.044; 2 , monoclinic, P21/n, a = 11.134(2) Å, b = 10.141(2) Å, c = 12.152(2) Å und β = 114.157(3)°, V = 1251.8(4) Å3, Z = 2, dc = 1.377 gcm—1, R1 = 0.0581; 3 , monoclinic, P21/n, a = 6.527(2) Å, b = 11.744(2) Å, c = 10.623(2), β = 96.644(3)°, V = 808.8(2) Å3, Z = 2, dc = 1.641 gcm—1, R1 = 0.0174; 4 , orthorhombic, Iba2, a = 23.266(5) Å, b = 9.541(2) Å, c = 12.867(3) Å, V = 2856(2) Å3, Z = 8, dc = 1.444 gcm—1, R1 = 0.0208; 5 , trigonal, P31, a = 13.945(2) Å, c = 30.011(6) Å, V = 5054(2) Å3, Z = 6, dc = 1.401 gcm—1; Rc = 0.0494.  相似文献   

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The new heteroleptic tungsten iodide cluster compound [W6I12(NCC6H5)2] is presented. The synthesis is carried-out from Cs2W6I14 and ZnI2 under solvothermal conditions in benzonitrile solution, yielding red cube-shaped crystals. [W6I12(NCC6H5)2] represents a heteroleptic [W6I8]-type cluster bearing four apical iodides and two benzonitrile ligands. Molecular [W6I12(NCC6H5)2] clusters form a robust hydrogen bridged crystal structure with high thermal stability and high resistibility against hydrolysis. The electronic structure is analyzed by quantum chemical methods of the calculated electron localization function (ELF) and the band structure. Photoluminescence measurements are performed to verify and describe the photophysical properties of [W6I12(NCC6H5)2]. Finally, the photocatalytic properties of [W6I12(NCC6H5)2] are evaluated as a proof-of-concept.  相似文献   

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Syntheses and Crystal Structures of [Cu4(As4Ph4)2(PRR′2)4], [Cu14(AsPh)6(SCN)2(PEt2Ph)8], [Cu14(AsPh)6Cl2(PRR′2)8], [Cu12(AsPh)6(PPh3)6], [Cu10(AsPh)4Cl2(PMe3)8], [Cu12(AsSiMe3)6(PRR′2)6], and [Cu8(AsSiMe3)4(PtBu3)4] (R, R′ = Organic Groups) Through the reaction of CuSCN with AsPh(SiMe3)2 in the presence of tertiary phosphines the compounds [Cu4(As4Ph4)2(PRR′2)4] ( 1 – 3 ) ( 1 : R = R′ = nPr, 2 : R = R′ = Et; 3 : R = Me, R′ = nPr) and [Cu14(AsPh)6(SCN)2(PEt2Ph)8] ( 4 ) can be synthesised. Using CuCl instead of CuSCN results to the cluster complexes [Cu14(AsPh)6Cl2(PRR′2)8] ( 5–6 ) ( 5 : R = R′ = Et; 6 : R = Me, R′ = nPr), [Cu12(AsPh)6(PPh3)6] ( 7 ) and [Cu10(AsPh)4Cl2(PMe3)8] ( 8 ). Through reactions of CuOAc with As(SiMe3)3 in the presence of tertiary phosphines the compounds [Cu12(AsSiMe3)6(PRR′2)6] ( 9 – 11 ) ( 9 : R = R′ = Et; 10 : R = Ph, R′ = Et; 11 : R = Et, R′ = Ph) and [Cu8(AsSiMe3)4(PtBu3)4] ( 12 ) can be obtained. In each case the products were characterised by single‐crystal‐X‐ray‐structure‐analyses. As the main structure element 1 – 3 each have two As4Ph42–‐chains as ligands. In contrast 4 – 12 contain discrete AsR2–ligands.  相似文献   

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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   

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The Cluster Azides M2[Nb6Cl12(N3)6]·(H2O)4—x (M = Ca, Sr, Ba) The isotypic cluster compounds M2[Nb6Cl12(N3)6] · (H2O)4—x (M = Ca (1) , M = Sr (2) and M = Ba (3) ) have been synthesized by the reaction of an aequeous solution of Nb6Cl14 with M(N3)2. 1 , 2 and 3 crystallize in the space group Fd3¯ (No. 227) with the lattice constants a = 1990.03(23), 2015.60(12) and 2043, 64(11) pm, respectively. All compounds contain isolated 16e clusters whose terminal positions are all occupied by orientationally disordered azide ligands.  相似文献   

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Black single crystals of [Lu(Db18c6)(H2O)3(thf)6]4(I3)2(I5)6(I8)(I12) were obtained from lutetium, I2 and Db18c6 (dibenzo‐18‐crown‐6) in THF solution. In the bulky cation, Lu3+ is surrounded by nine oxygen atoms, six of Db18c6 and three of water molecules to which two THF molecules are attached each. Meanwhile, four polyiodide anions, (I3), (I5), (I8)2– and (I12)2–, in a 2:6:1:1 ratio form a three‐dimensional network and leave space for the bulky cations.  相似文献   

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Syntheses, Crystal Structures, and Triple Twinning of the Cluster Trimers Bi2[PtBi6Br12]3 and Bi2[PtBi6I12]3 Melting reactions of Bi with Pt and BiX3 (X = Br, I) yield shiny black, air insensitive crystals of the subhalides Bi2[PtBi6X12]. Bi2[PtBi6Br12]3 crystallizes in the monoclinic space group C2/m with lattice parameters a = 1617.6(2) pm, b = 1488.5(1) pm, c = 1752.4(2) pm, and β = 110.85(4)°. Bi2[PtBi6I12]3 adopts the triclinic space group with pseudo‐monoclinic lattice parameters a = 1711.2(2) pm, b = 1585.1(1) pm, c = 1865.7(2) pm, and α = 90°, β = 111.15(4)°, γ = 90°. The two homoeotypic compounds consist of cuboctahedral [Pt?IIBiII6X?I12]2? clusters that are concatenated into linear trimers by BiIII atoms. The ordered distribution of BiIII atoms destroys the inherent threefold rotation axes in the packing of cluster anions. As a consequence of the pseudosymmetry the crystals are triple twinned along [201]. Due to different orientations of the cluster trimers there are two BiII···X inter‐cluster bridges per BiII atom in Bi2[PtBi6Br12]3 but only one bridge in Bi2[PtBi6I12]3. The structure of the iodine compound can be deduced from the NaCl structure type, leaving 37 of 96 atomic positions unoccupied. The arrangement of the cuboctahedral clusters follows the motif of a body‐centered cubic packing.  相似文献   

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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   

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