Zwei Chloridsilicate des Yttriums: Y3Cl[SiO4]2 und Y6Cl10[Si4O12]

Two Chloride Silicates of Yttrium: Y₃Cl[SiO₄]₂ and Y₆Cl₁₀[Si₄O₁₂] The chloride‐poor yttrium(III) chloride silicate Y₃Cl[SiO₄]₂ crystallizes orthorhombically (a = 685.84(4), b = 1775.23(14), c = 618.65(4) pm; Z = 4) in space group Pnma. Single crystals are obtained by the reaction of Y₂O₃, YCl₃ and SiO₂ in the stoichiometric ratio 4 : 1 : 6 with ten times the molar amount of YCl₃ as flux in evacuated silica tubes (7 d, 1000 °C) as colorless, strongly light‐reflecting platelets, insensitive to air and water. The crystal structure contains isolated orthosilicate units [SiO₄]^4– and comprises cationic layers {(Y2)Cl}²⁺ which are alternatingly piled parallel (010) with anionic double layers {(Y1)₂[SiO₄]₂}^2–. Both crystallographic different Y³⁺ cations exhibit coordination numbers of eight. Y1 is surrounded by one Cl^– and 7 O^2– anions as a distorted trigonal dodecahedron, whereas the coordination polyhedra around Y2 show the shape of bicapped trigonal prisms consisting of 2 Cl^– and 6 O^2– anions. The chloride‐rich chloride silicate Y₆Cl₁₀[Si₄O₁₂] crystallizes monoclinically (a = 1061,46(8), b = 1030,91(6), c = 1156,15(9) pm, β = 103,279(8)°; Z = 2) in space group C2/m. By the reaction of Y₂O₃, YCl₃ and SiO₂ in 2 : 5 : 6‐molar ratio with the double amount of YCl₃ as flux in evacuated silica tubes (7 d, 850 °C), colorless, air‐ and water‐resistant, brittle single crystals emerge as pseudo‐octagonal columns. Here also a layered structure parallel (001) with distinguished cationic double‐layers {(Y2)₅Cl₉}⁶⁺ and anionic layers {(Y1)Cl[Si₄O₁₂]}^6– is present. The latter ones contain discrete cyclo‐tetrasilicate units [Si₄O₁₂]^8– of four cyclically corner‐linked [SiO₄] tetrahedra in all‐ecliptical arrangement. The coordination sphere around (Y1)³⁺ (CN = 8) has the shape of a slightly distorted hexagonal bipyramid comprising 2 Cl^– and 6 O^2– anions. The 5 Cl^– and 2 O^2– anions building the coordination polyhedra around (Y2)³⁺ (CN = 7) form a strongly distorted pentagonal bipyramid.     

ChemInform Abstract: Tetrayttrium Difluoride Disilicate Orthosilicate,Y4F2[Si2O7][SiO4].

Colorless lath-shaped single crystals of the title compound are obtained from a melt of Y₂O₃, YF₃, and SiO₂ (2:5:3 molar ratio) using CsCl as a flux (evacuated silica tube, 973 K, 9 d, 10 K/h cooling rate).     

Synthesis and Structure of Ba7F12Cl2

Crystals of ordered and disordered Ba₇F₁₂Cl₂ were prepared by flux growth and solid state reactions. These new structures were characterized by single crystal and powder X‐ray diffraction. The disordered variant which shows disorder on one of the cation sites was obtained from a BaF₂ + BaCl₂ + NaCl/NaF flux. It has hexagonal space group P6₃/m (176) with one formula unit per unit cell. The lattice constants are a = b = 1059.55(5) pm and c = 420.10(4) pm (at 21 °C). The structure was refined to R(R_w) = 0.026(0.030) for 346 independent reflections and 26 parameters. Slow cooling of a mixture of BaF₂ and LiCl yields the ordered variant. This one crystallizes in the hexagonal space group P6 (174) with one formula per unit cell. Lattice constants at 21 °C are a = b = 1063.46(2) pm and c = 417.52(1) pm. The structure was refined to R(R_w) = 0.017 (0.017) for 638 independent reflections and 45 parameters. The structural arrangement and the interatomic distances of the two variants are mutually similar. The barium atoms have coordination number nine. Propeller‐type arrangements with a chloride ion on the axis and the fluoride ions as blades are observed. These latter ones are interconnected into ‘channels' of tricapped fluoride prisms. Occupation disorder of the barium sites in the channels of the disordered variant makes the main difference between the two. An unexpectedly high X‐ray density obtained for both variants of Ba₇F₁₂Cl₂ can be correlated to the density of other barium fluorohalides having a coordination number of nine for the barium ion.     

Sm3Cl[SiO4]2: Ein chlorarmes Chloridorthosilicat des Samariums

Sm₃Cl[SiO₄]₂: A Chlorine‐poor Chloride Orthosilicate of Samarium Pale yellow, plate‐like single crystals of Sm₃Cl[SiO₄]₂ (orthorhombic, Pnma; a = 701.74(8), b = 1800.8(2), c = 626.63(7) pm; Z = 4) are obtained upon the reaction of SmCl₃, Sm₂O₃ and SiO₂ (”︁Kieselgel”︁”︁) in 1 : 4 : 6 molar ratios, most advantageously in the presence of substantial amounts of NaCl as fluxing agent, after seven days at 850 °C in evacuated silica ampoules. The B‐type crystal structure (isotypic with e. g. Yb₃Cl[SiO₄]₂) contains discrete orthosilicate tetrahedra [SiO₄]^4– which form anionic double layers ({(Sm1)₂[SiO₄]₂}^2–) with (Sm1)³⁺. These are alternatingly sheethed along [010] with cationic monolayers ({(Sm2)Cl}²⁺) consisting of (Sm2)³⁺ and Cl^–. Both crystallographically independent Sm³⁺ cations exhibit coordination numbers of eight (Sm1: 1 Cl + 7 O; Sm2: 2 Cl + 6 O) with respect to the involved electronegative particles.     

The polyoxometallate [(CH3)4N]2[Mo4O10(OCH3)4Cl2]

The crystal and molecular structure of bis(tetra­methyl­ammonium) di­chloro­tetra‐μ₂‐methoxo‐di‐μ₂‐oxo‐octo­oxo­tetra­molybdate(VI), (C₄H₁₂N)₂[Mo₄O₁₀(OCH₃)₄Cl₂], has been determined from X‐ray diffraction data. The crystallographically centrosymmetric anion is built up of four edge‐sharing octahedra, two MoO₆ and two MoO₅Cl.     

Na2[Pr4O2]Cl9 und K2[Pr4O2]Cl9, die ersten reduzierten quaternären Praseodymchloride mit anti-SiS2-analogen [Pr4/2O]-Ketten

Na₂[Pr₄O₂]Cl₉ and K₂[Pr₄O₂]Cl₉, the First Reduced Quaternary Praseodymium Chlorides with Anti-SiS₂ Analogous [Pr_4/2O] Chains The compounds A₂[Pr₄O₂]Cl₉ (A = Na, K) are the first reduced quaternary praseodymium chlorides with anti-SiS₂ analogous [Pr_4/2O] chains. Synthesis took place in the temperature range from 900 to 600°C in silica-jacketed niobium containers from Pr metal, PrCl₃, PrOCl and NaCl (KCl) as starting materials. The X-ray structure analysis of a single crystal of Na₂[Pr₄O₂]Cl₉ (monoclinic, P2₁/m (No. 11), Z = 2, a = 812.2(2) pm, b = 1 134.1(2) pm, c = 937.6(2) pm, β = 106.51(2)°, R = 0.048, R_w = 0.037) exhibits trans-edge connected chains of [Pr_4/2O] tetrahedra running along [001] which are connected by surrounding common chloride ions forming layers parallel to (001). These layers are connected by further chloride ions to a three-dimensional network. The sodium ions surrounded by a heavily distorted octahedron of chloride ions are placed between the layers. The X-ray structure analysis of a single crystal of the otherwise isotypic K₂[Pr₄O₂]Cl₉ (monoclinic, P2₁/m (No. 11), Z = 2, a = 820.6(2) pm, b = 1 133.2(4) pm, c = 949.2(3) pm, β = 103.94(2)°, R = 0.073, R_w = 0.054) shows that potassium is coordinated by nine chloride ions.     

V2O2F4(H2O)2·H2O: a new V4+ layer structure related to VOF3

V^IV oxyfluorides are of interest as frustrated magnets. The successful synthesis of two‐dimensionally connected vanadium(IV) oxyfluoride structures generally requires the use of ionic liquids as solvents. During solvothermal synthesis experiments aimed at producing two‐ and three‐dimensional vanadium(IV) selenites with triangular lattices, the title compound, diaquatetra‐μ‐fluorido‐dioxidodivanadium(IV) monohydrate, V₂O₂F₄(H₂O)₂·H₂O, was discovered and features a new infinite V⁴⁺‐containing two‐dimensional layer comprised of fluorine‐bridged corner‐ and edge‐sharing VOF₄(H₂O) octahedral building units. The synthesis was carried out under solvothermal conditions. The V⁴⁺ centre exhibits a typical off‐centring, with a short V=O bond and an elongated trans‐V—F bond. Hydrogen‐bonded water molecules occur between the layers. The structure is related to previously reported vanadium oxyfluoride structures, in particular, the same layer topology is seen in VOF₃.     

Gas-phase fragmentation reactions of protonated glycerol and its oligomers: Metastable and collision-induced dissociation reactions,associated deuterium isotope effects and the structure of [C3H5O]+, [C2H5O]+, [C2H4O]+. and [C2H3O]+ ions

The chemistry of glycerol subjected to a high-energy particle beam was explored by studying the mass spectral fragmentation characteristics of gas-phase protonated glycerol and its oligomers by using tandem mass spectrometry. Both unimolecular metastable and collision-induced dissociation reactions were studied. Collision activation of protonated glycerol results in elimiation of H₂O and CH₃OH molecules. The resulting ions undergo further fragmentations. The origin of several fragment ions was established by obtaining their product and precursor ion spectra. Corresponding data for the deuterated analogs support those results. The structures of the fragment ions of compositions [C₃H₅O]⁺, [C₂H₅O]⁺, [C₂H₄O]^+. and [C₂H₃O]⁺ derived from protonated glycerol were also identified. Proton-bound glycerol oligomers fragment principally via loss of neutral glycerol molecules. Dissociation of mixed clusters of glycerol and deuterated glycerol displays normal secondary isotope effects.     

Zur Dimorphie von Nd3Cl[SiO4]2

On the Dimorphism of Nd₃Cl[SiO₄]₂ On reacting NdCl₃, Nd₂O₃, and SiO₂ (molar ratio: 1 : 4 : 6) at 850 °C in evacuated silica tubes, pale violet, hydrolysis resistant neodymium(III) chloride ortho‐silicate Nd₃Cl[SiO₄]₂ can be obtained within seven days. If equimolar amounts of NaCl are added as flux, rod‐ or platelet‐shaped, transparent single crystals of two modifications accumulate simultaneously. The one with the higher density (A‐Nd₃Cl[SiO₄]₂) crystallizes monoclinically (C2/c, no. 15; a = 1416.6(1), b = 638.79(6), c = 872.21(9) pm, β = 98.403(7)°; V_m = 117.55 cm³/mol, Z = 4), whereas the one with the lower density (B‐Nd₃Cl[SiO₄]₂) exhibits orthorhombic symmetry (Pnma, no. 62; a = 709.36(7), b = 1815.7(2), c = 631.48(6) pm; V_m = 122.45 cm³/mol, Z = 4). Two crystallographically independent Nd³⁺ cations exist in each of both crystal structures, which in the A type are surrounded by nine (1 Cl^– + 8 O^2–) and ten (2 Cl^– + 8 O^2–), whilst those in the B type by only two times eight (1 Cl^– + 7 O^2– and 2 Cl^– + 6 O^2–) anions, respectively. Thereby all oxygen atoms of both forms represent members of discrete ortho‐silicate tetrahedra ([SiO₄]^4–). Although both crystal structures are built of alternating anionic double layers {(Nd1)₂[SiO₄]₂}^2– and cationic single layers {(Nd2)Cl}²⁺, there is a higher cross‐linkage of the building units in the A‐type lattice, where the cations are coordinated by three and four tetrahedra edges of ortho‐silicate anions, compared to only two times two of them in the B type. From this an about 4% higher density of Nd₃Cl[SiO₄]₂ results for the A‐type structure (D_x = 5.55 g/cm³) in comparison with B‐type Nd₃Cl[SiO₄]₂ (D_x = 5.33 g/cm³).     

Investigation of Large Polychloride Anions: [Cl11]−, [Cl12]2−, and [Cl13]−

For decades the chemistry of polyhalides was dominated by polyiodides and more recently also by an increasing number of polybromides. However, apart from a few structures containing trichloride anions and a single report on an octachloride dianion, [Cl₈]^2?, polychlorine compounds such as polychloride anions are unknown. Herein, we report on the synthesis and investigation of large polychloride monoanions such as [Cl₁₁]^? found in [AsPh₄][Cl₁₁], [PPh₄][Cl₁₁], and [PNP][Cl₁₁]?Cl₂, and [Cl₁₃]^? obtained in [PNP][Cl₁₃]. The polychloride dianion [Cl₁₂]^2? has been obtained in [NMe₃Ph]₂[Cl₁₂]. The novel compounds have been thoroughly characterized by NMR spectroscopy, single‐crystal Raman spectroscopy, and single‐crystal X‐ray diffraction. The assignment of their spectra is supported by molecular and periodic solid‐state quantum‐chemical calculations.     

K2[Mo2O4(C2O4)2(H2O)2]·3H2O

The crystal and molecular structure of dipotassium di‐μ‐oxo‐bis[aqua(oxalato‐O¹,O²)oxomolybdenum(III)] trihydrate, K₂­[Mo₂O₄(C₂O₄)₂(H₂O)₂]·3H₂O, has been determined from X‐ray diffraction data. In the dimeric anion, which has approximate twofold symmetry, each Mo atom is in a distorted octahedral coordination, being bonded to one terminal oxo‐O atom, two bridging O atoms, two O atoms from the oxalato ligand and one from the water mol­ecule. Bond lengths trans to the multiple‐bonded terminal oxo ligand are larger than those in the cis position, confirming the trans influence as a generally valid rule.     

Decarboxylative Trifluoromethylating Reagent [Cu(O2CCF3)(phen)] and Difluorocarbene Precursor [Cu(phen)2][O2CCF2Cl]

This article describes the new economic decarboxylative trifluoromethylating reagent [Cu(phen)(O₂CCF₃)] ( 1 ; phen=1,10‐phenanthroline) and the efficient difluorocarbene precursor [Cu(phen)₂][O₂CCF₂Cl] ( 2 ). Treatment of copper tert‐butoxide with phen and subsequent addition of trifluoroacetic acid or chlorodifluoroacetic acid afforded air‐stable complexes 1 and 2 , respectively, which were characterized by X‐ray crystallography. The copper(I) ion in 1 is coordinated by a bidentate phen ligand, a monodentate trifluoroacetate group, and a molecule of CH₃CN in a distorted tetrahedral coordination geometry. The molecular structure of 2 adopts an ionic form that consists of a [Cu(phen)₂]⁺ cation and a chlorodifluoroacetate anion. Complex 1 reacted with a variety of aryl and heteroaryl halides to form trifluoromethyl (hetero)arenes in good yields. The corresponding Hammett plot exhibited a linear relationship and a reaction parameter (ρ)=+0.56±0.02, which indicated that the trifluoromethylation reaction proceeded via a nucleophilic reactive species. Complex 2 reacts with phenols to produce aryl difluoromethyl ethers in modest‐to‐excellent yields. Mechanistic investigations revealed that the difluoromethylation reaction proceeds by initial copper‐mediated formation of difluorocarbene and subsequent concerted addition of difluorocarbene to the phenol to form a three‐center transition state.     

Metallampullen als Mini‐Autoklaven: Synthese und Kristallstrukturen der Ammoniakate [Al(NH3)4Cl2][Al(NH3)2Cl4] und (NH4)2[Al(NH3)4Cl2][Al(NH3)2Cl4]Cl2

Metal Ampoules as Mini‐Autoclaves: Syntheses and Crystal Structures of [Al(NH₃)₄Cl₂][Al(NH₃)₂Cl₄] and (NH₄)₂[Al(NH₃)₄Cl₂][Al(NH₃)₂Cl₄]Cl₂ The salts [Al(NH₃)₄Cl₂]⁺[Al(NH₃)₂Cl₄]^–≡AlCl₃ · 3 NH₃ ( 1 ) and (NH₄⁺)²[Al(NH₃)₄Cl₂]⁺[Al(NH₃)₂Cl₄]^–(Cl^–)₂≡ AlCl₃ · 3 NH₃ · (NH₄)Cl ( 2 ) have been obtained as single crystals during the reactions of aluminum and aluminum trichloride, respectively, with ammonium chloride in sealed Monel metal containers. The crystal structure of 1 was determined again [triclinic, P‐1; a = 574.16(10); b = 655.67(12); c = 954.80(16) pm; α = 86.41(2); β = 87.16(2); γ = 84.89(2)°], that of 2 for the first time [monoclinic, I2/m; a = 657.74(12); b = 1103.01(14); c = 1358.1(3) pm; β = 103.24(2)°].     

Cs[Cl3F10]: A Propeller‐Shaped [Cl3F10]− Anion in a Peculiar A[5]B[5] Structure Type

Reaction of CsF with ClF₃ leads to Cs[Cl₃F₁₀]. It contains a molecular, propeller‐shaped [Cl₃F₁₀]^? anion with a central μ₃‐F atom and three T‐shaped ClF₃ molecules coordinated to it. This anion represents the first example of a heteropolyhalide anion of higher ClF₃ content than [ClF₄]^? and is the first Cl‐containing interhalogen species with a μ‐bridging F atom. The chemical bonds to the central μ₃‐F atom are highly ionic and quite weak as the bond lengths within the coordinating XF₃ units (X = Cl, and also calculated for Br, I) are almost unchanged in comparison to free XF₃ molecules. Cs[Cl₃F₁₀] crystallizes in a very rarely observed A^[5]B^[5] structure type, where cations and anions are each pseudohexagonally close packed, and reside, each with coordination number five, in the trigonal bipyramidal voids of the other.     

一个新颖镍配位阳离子修饰的还原型钼磷酸盐：Ni[Mo6O12(OH)3(PO4)(HPO4)3]2][Ni(H2O)2][Ni(H2O)(bipy)2]4·5H2O

水热合成并通过红外、热重、单晶X-射线衍射表征了一个新颖镍配位阳离子修饰的还原型钼磷酸盐,Ni[Mo₆O₁₂(OH)₃(PO₄)(HPO₄)₃]₂][Ni(H₂O)₂][Ni(H₂O)(bipy)₂]₄·5H₂O。单晶X-射线衍射研究表明,两个{Mo₆P₄}簇单元通过一个镍离子连接形成一个Ni[Mo₆P₄]₂二聚结构单元,其进一步和其他的镍配位阳离子连接成钼磷酸盐一维链状结构。在H₂O₂存在下的液－固体系中,使用该化合物催化氧化苯甲醛的探针反应结果表明,该化合物具有较高的催化氧化活性。     

[Te8]2[Ta4O4Cl16]: A Two‐dimensional Tellurium Polycation obtained via Ionic Liquid‐Based Synthesis

By reaction of elemental tellurium, tellurium(IV) chloride, tantalum(V) chloride and tantalum(V) oxychloride in the ionic liquid [BMIM]Cl ([BMIM]Cl:1‐Butyl‐3‐methylimidazolium chloride),[Te₈]₂[Ta₄O₄Cl₁₆] is obtained in the form of lucent black crystals. The title compound consists of infinite [Te–Te–(Te₆)]_n²⁺ chains (Te–Te: 264.9(1)–284.3(1) pm) and isolated [Ta₄O₄Cl₁₆]^4– anions. The [Te–Te–(Te₆)]_n²⁺ chains are interconnected to form a two‐dimensional tellurium network (Te–Te: 335.9 pm). Due to this interaction the [Te–Te–(Te₆)]_n²⁺ chains in [Te₈]₂[Ta₄O₄Cl₁₆] show an arrangement that differs significantly from known polycationic [Te₈]_n²⁺ chains. The two‐dimensional tellurium network is finally separated by tetrameric, corner‐sharing oxidochloridotantalate anions [(TaO_2/2Cl_4/1)₄]^4– that are firstly observed. The composition of [Te₈]₂[Ta₄O₄Cl₁₆] is confirmed by EDX analysis; its optical band gap is estimated to 1.1–1.2 eV via UV/Vis spectroscopy.     

(C5H6N4O)(C5H5N4O)3(C5H4N4O)[Bi2Cl11]Cl2 as a simple and efficient catalyst in Biginelli reaction

A highly efficient and facile procedure for the one‐pot three‐component synthesis of 3,4‐dihydropyrimidin‐2‐(1H )ones/thiones from the one‐pot condensation of aldehyde, β‐dicarbonyl compound and urea/thiourea was developed. The methodology is applicable to a wide range of substrates with high yield in the presence of (C₅H₆N₄O)(C₅H₅N₄O)₃(C₅H₄N₄O)[Bi₂Cl₁₁]Cl₂. The complex is an air‐stable, environmentally friendly and recoverable catalyst and can efficiently catalyze the Biginelli reaction. The catalyst has high catalytic efficiency with low catalyst loading, and can be recycled ten times with only a small loss of activity.     

Two New Benzoate‐di(methylcyclopentadienyl)ytterbium(III) Complexes: [Yb(MeCp)2(O2CC6F5)]2 and [Yb(MeCp)2(O2C‐o‐HC6F4)]2

Transparent orange crystals of [Yb(MeCp)₂(O₂CC₆F₅)]₂ and [Yb(MeCp)₂(O₂C‐o‐HC₆F₄)]₂ were obtained by oxidation of Yb(MeCp)₂ with M(O₂CR) (M = ¹/₂ Hg, Tl; R = C₆F₅, o‐HC₆F₄) in tetrahydrofuran. They have a dimeric structure with bridging bidentate (O, O')‐benzoate groups and eight coordinated ytterbium. Both crystallise isotypic in the orthorhombic space group Pbca. Room temperature as well as low temperature single crystal X‐ray investigations show the o‐H/F positions in [Yb(MeCp)₂(O₂C‐o‐HC₆F₄)]₂ not to be ordered.     

ChemInform Abstract: Polychloride Monoanions from [Cl3]‐ to [Cl9]‐: A Raman Spectroscopic and Quantum Chemical Investigation.

Polychloride monoanions [Cl_n]^‐ (n = 3, 5, 7, 9) stabilized by quaternary ammonium salts are obtained through the addition or condensation of an excess of dry chlorine to [NMe₄]Cl, [NEt₄]Cl, [NPr₄]Cl, or [NBu₄]Cl and characterized by Raman spectroscopy and state‐of‐the‐art quantum chemical calculations up to the CCSD(T) level.