Kationische und anionische kantenverknüpfte Dimere in [Dy2(Dibenzo-18-Krone-6)2Cl4][Dy2(CH3CN)2Cl8]. Synthese und Kristallstruktur

Cationic and Anionic Edge-Connected Dimers in [Dy₂(dibenzo-18-crown-6)₂Cl₄][Dy₂(CH₃CN)₂Cl₈]. Synthesis and Crystal Structure Colourless single crystals of 2 DyCl₃ · dibenzo-18-crown-6 · CH₃CN are obtained upon reaction of DyCl₃ or KDy₂Cl₇ with dibenzo-18-crown-6-ether in acetonitrile. The crystal structure (triclinic, P1 , Z = 2; a = 1 105.6(2); b = 1 144.5(3); c = 1 367.8(3); α = 93.46(1); β = 92.27(1); γ = 117.45(1); R = 0.046; R_w = 0.033) contains cationic and anionic edge-connected dimers according to [Dy₂(dibenzo-18-crown-6)₂Cl₄]²⁺ [Dy₂(CH₃CN)₂Cl₈]²⁺ where Dy1 and Dy2 are coordinated by 3 and 5 chloride ions, respectively.     

STRUCTURAL STUDIES OF POLYETHER COORDINATION TO MERCURY(II) HALIDES: CROWN ETHER VERSUS POLYETHYLENE GLYCOL COMPLEXATION

Abstract

The crystal structures of several crown ether and polyethylene glycol complexes of HgX₂ (X=Cl, Br, I) have been investigated. The crown ether complexes studied are [HgX₂(18-crown-6)] (X=Br, I) and [HgI₂(dibenzo-18-crown-6)]·CH₃CN. In each case Hg resides in the cavity of the ether resulting in hexagonal bipyramidal geometry with axial, terminal halides. The covalently bonded halides reside closer to Hg than the oxygen donor atoms. Five polyethylene glycol complexes have been structurally characterized: [(HgCl₂)₃(EO3)], [HgX₂(EO4)] (X=Br, I), [HgCl₂(EO5)], and [HgBr₂(EO5)HgBr₂]₂ (EO3=triethylene glycol, EO4=tetraethylene glycol, EO5=pentaethylene glycol). The EO4 and EO5 glycols mimic crown ethers by forming an equatorial girdle around Hg although in each case one alcoholic terminal end does not coordinate to the metal ion. Each complex also has two covalent, nearly linear, axial halides coordinated to Hg. In [(HgCl₂)₃(EO3)], the glycol is linear and coordinates to three Hg atoms all on the same side of the glycol ligand. This structure is polymeric via chloride bridging.     

Synthesis and crystal structure of hexakis(isothiocyanato)erbium(III) thiocyanate bis(18-crown-6)dipotassium bis[(18-crown-6)ethanolpotassium]

A new complex compound, [K₂(18-crown-6)₂[K(18-crown-6)(EtOH)]₂[Er(NCS)₆](SCN) (I), was synthesized and its crystal structure was studied by X-ray diffraction. In this work, the synthes and X-ray difraction stady of the crystals of a new complex, hexakis (isothiocyanato) erbiu(III) thiocyanate bis(18-crown-6) dipotassium bis(18-crown-6) ethanolpotassium], [K₂(18-crown-6)₂][K(18-crown-6)(ETON)]₂[Er(NCS)₆(SCN)(I)] are described. In crystal I, the alternating [Er(NCS)₆]^3? anions and binuclear complex cation [K(18-crown-6)₂]²⁺ from infinite chains via the F-S bonds, while two complex cations [K(18-crown-6)(ETON)]⁺ and the statistically disordered SCN^? anion between them are linked by the hydragen bonds O-H…S and O-H…N. Complex I contains the host-guest complex cations [K₂(18-crown-6)₂)]²⁺ and [K(18-crown-6)(ETON)]⁺ [1]. The alternating octabedral [Er(NCS)₆]^3? anions and binuclear complex cations [K₂(18-crown-6)₂]²⁺of crystal I form infinite chains via the K-S bonds, while two complex cations [K(18-crown-6)(EtOH)]⁺ and the statistically disordered SCN^? anion lying between them are linked by interionic hydrogen bonds O-H…S and O-H…N. Complex I contains the host-guest complex cations [K₂(18-crown-6)₂]²⁺ and [K(18-crown-6)(EtOH)]⁺ [1].     

Über die Kronenetherkomplexe [K(15-Krone-5)2]3[Sb3I12], [TeCl3(15-Krone-5)][TeCl5] und [TeCl3(15-Krone-5)]2[TeCl6]

On the Crown Ether Complexes [K(15-Crown-5)₂]₃[Sb₃I₁₂], [TeCl₃(15-Crown-5)][TeCl₅], and [TeCl₃(15-Crown-5)]₂[TeCl₆] Orange-coloured crystals of [K(15-crown-5)₂]₃[Sb₃I₁₂] are formed in the reaction of potassium iodide with antimony triiodide and 15-crown-5 in acetonitrile solution. An X-ray structure determination reveals severe disorder of the crown ether molecules, which coordinate to the potassium atoms in a sandwich array; so only the [Sb₃I₁₂]^3? ion and the potassium positions were ascertained. The anion is a centrosymmetric trimer (symmetry C_2h), which can be understood as central SbI₆^3? ion, coordinated by two SbI₃ molecules. (Space group C2/m), Z = 2, 3263 observed, independent reflections, R = 0.06, lattice dimensions at 20°C: a = 2541.1 pm, b = 1441.7 pm, c = 1588.4 pm, β = 113.33°. The tellurium complexes [TeCl₃(15-crown-5)] [TeCl₅] and [TeCl₃(15-crown-5)]₂[TeCl₆] are prepared by reaction of TeCl₄ with 15-crown-5 in acetonitrile solution, forming yellow-green crystals sensitive to moisture. They are characterized by their i.r. spectra.     

Nitrosyltechnetium(I) Complexes with 2‐(Diphenylphosphanyl)aniline

[Tc^I(NO)Cl(H₂L1)₂]⁺ cations (H₂L1 = 2‐(diphenylphosphanyl)aniline) are formed during reactions of H₂L1 with (NBu₄)[Tc(NO)Cl₄(MeOH)] or (NH₄)TcO₄/HCl/NH₂OH mixtures. Different isomers were isolated depending on the counterions and solvents used. The technetium(I) complexes cis‐NO,Cl,trans‐P,P‐[Tc^I(NO)Cl(H₂L1)₂]Cl, trans‐NO,Cl,cis‐P,P‐[Tc^I(NO)Cl(H₂L1)₂]₂(TcCl₆), and trans‐NO,Cl,trans‐P,P‐[Tc^I(NO)Cl(H₂L1)₂](PF₆) were isolated in crystalline form and studied by spectroscopic methods and X‐ray crystallography. DFT calculations show that there are only minor energy differences between the three isomers and the formation of the individual compounds is most probably strongly influenced by interactions with solvents and counterions.     

Ionische Kronenetherkomplexe von Zinn(II) und Zinn(IV): [Sn(15-Krone-5)] [SnCl6] und [SnCl3(18-Krone-6)]2[Sn2Cl10]; Synthesen,IR-Spektren und 119Sn-Mößbauer-Spektren

Ionic Crown Ether Complexes of Tin(II) and Tin(IV): [Sn(15-Crown-5)][SnCl₆] and [SnCl₃(18-Crown-6)]₂[Sn₂Cl₁₀]; Syntheses, IR Spectra, and ¹¹⁹Sn-Mössbauer Spectra [Sn(15-crown-5)][SnCl₆] ( 1 ,) has been prepared by the reaction of SnCl₂, SnCl₄, and 15-crown-5 in the molar ratio of 1 : 1 : 1 in acetonitrile solution, forming a white insoluble crystal powder. [SnCl₃(18-crown-6)]₂[Sn₂Cl₁₀] ( 2 ,) as well as [SnCl₃(18-crown-6)][BiCl₄] · CH₃CN ( 3 ,) are prepared by the reaction of SnCl₄ with 18-crown-6 (molar ratio 2 : 1), and of SnCl₄, 18-crown-6, and BiCl₃ (molar ratio 1 : 1 : 1), respectively. According to IR-spectroscopy and ¹¹⁹Sn-Mössbauer-spectroscopy 1–3 , have ionic structures; the cation of 1 , being polymeric via a sandwich-like structure.     

(18-Crown-6)potassium tetrachloroferrate(III), dibromodichloroferrate(III), and tetrabromoferrate(III): Synthesis and crystal structures

Three new crystalline complexes are synthesized: [K(18-crown-6)]⁺ · An, where An = [FeCl₄]^?(I), [FeBr₂Cl₂]^? (II), and [FeBr₄]^? (III). The crystals of compounds I–III are cubic and isomorphic, space group Fd $ \bar 3 Three new crystalline complexes are synthesized: [K(18-crown-6)]⁺ · An, where An = [FeCl₄]⁻(I), [FeBr₂Cl₂]⁻ (II), and [FeBr₄]⁻ (III). The crystals of compounds I–III are cubic and isomorphic, space group Fd (Z = 16): a = 20.770(2) ? for I, 20.844(3) ? for II, and 20.878(4) ? for III. Structures I–III are solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.047 (I), 0.059 (II), and 0.098 (III) for all 680 (I), 684 (II), and 686 (III) independent reflections. In two tetrahedral anions [Fe(1)X₄]⁻ and [Fe(2)X₄]⁻ in structures I–III, all halogen atoms (X = Cl and Br) are randomly disordered over three close positions relative to the crystallographic axes 3. Structures I–III contain the [K(18-crown-6)]⁺ host-quest complex cation. The K⁺ cation (CN = 8) resides in the cavity of the 18-crown-6 ligand and coordinated by its six O atoms and two disordered halogen X atoms. The coordination polyhedron of the K⁺ cation in complexes I–III is a distorted hexagonal bipyramid. Original Russian Text ? A.N. Chekhlov, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 9, pp. 1566–1570.     

(18-Crown-6)potassium 0.84(diiodobromide) 0.16(dibromoiodide) and diaqua(18-Crown-6)chlororubidium: Syntheses and crystal structures

New host-guest compounds are synthesized and studied by X-ray diffraction analysis: (18-crown-6) potassium 0.84(diiodobromide) 0.16(dibromoiodide), [K(18-crown-6)]⁺ · (Br_1.16I_1.84)⁻, (I) and diaqua (18-crown-6)chlororubidium, [RbCl(18-crown-6)(H₂O)₂], (II). The crystals of compound I are monoclinic (space group P2₁/n, a = 9.157 ?, b = 8.589 ?, c = 14.072 ?, β = 102.27°, Z = 2). The structure of compound II is orthorhombic (space group Pnma, a = 9.813 ?, b = 15.231 ?, c = 12.629 ?, Z = 4). The structures are solved by a direct method and refined by the full-matrix anisotropic least squares to R = 0.062 (I) and 0.079 (II) for 3149 (I) and 2840 (II) independent reflections (CAD-4 automated diffractometer, λMoK _α radiation). The crystal structures of compounds I and II are different: compound I is built of infinite chains of the alternating cations [K(18-crown-6)]⁺ and mixed halide anions linked by weak coordination bonds K-Br or K-I, whereas individual molecules [RbCl(18-crown-6)(H₂O)₂] form structure II. Original Russian Text ? A.N. Chekhlov, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 8, pp. 1385–1391.     

Die Kristallstrukturen von (NH4)2[ReCl6], [ReCl2(CH3CN)4]2[ReCl6] · 2CH3CN und [ReCl4(18-Krone-6)]

The Crystal Structures of (NH₄)₂[ReCl₆], [ReCl₂(CH₃CN)₄]₂[ReCl₆] · 2CH₃CN and [ReCl₄(18)(Crown-6)] Brown single crystals of (NH₄)₂[ReCl₆] are formed by the reaction of NH₄Cl with ReCl₅ in a suspension of diethylether. [ReCl₂(CH₃CN)₄]₂[ReCl₆] · 2CH₃CN crystallizes as brown crystal plates from a solution of ReCl₅ in acetonitrile. Lustrous green single crystals of [ReCl₄(18-crown-6)] are obtained by the reaction of 18-crown-6 with ReCl₅ in a dichloromethane suspension. All rhenium compounds are characterized by IR spectroscopy and by crystal structure determinations. (NH₄)₂[ReCl₆]: Space group Fm3 m, Z = 4, 75 observed unique reflections, R = 0.01. Lattice constant at ?70°C: a = 989.0(1) pm. The compound crystallizes in the (NH₄)₂[PtCl₆] type, the Re? Cl distance is 235.5(1) pm. [ReCl₂(CH₃CN)₄]₂[ReCl₆] · 2CH₃CN: Space group P1, Z = 1, 2459 observed unique reflections, R = 0.12. Lattice dimensions at ?60°C: a = 859.0(1), b = 974.2(7), c = 1287.3(7) pm, α = 102.69(5)°, b? = 105.24(7)°, γ = 102.25(8)°. The structure consists of two symmetry-independent [ReCl₂(CH₃CN)₄]⁺ ions with trans chlorine atoms, [ReCl₆]^2? ions, and included acetonitrile molecules. In the cations the Re? Cl bond lengths are 233 pm in average, in the anion they are 235 pm in average. [ReCl₄(18-crown-6)]: Space group P2₁/n, Z = 4, 3 633 observed unique reflections, R = 0.06. Lattice dimensions at ?70°C: a = 1040.2(4), b = 1794.7(5), c = 1090.0(5) pm, b? = 108.91(4)°. The compound forms a molecular structure, in which the rhenium atom is octahedrally coordinated by the four chlorine atoms and by two oxygen atoms of the crown ether molecule.     

Kronenetherkomplexe von Blei(II). Die Kristallstrukturen von [PbCl(18-Krone-6)][SbCl6], [Pb(18-Krone-6)(CH3CN)3][SbCl6]2, and [Pb(15-Krone-5)2][SbCl6]2

Crown Ether Complexes of Lead(II). The Crystal Structures of [PbCl(18-Krone-6)][SbCl₆], [Pb(18-Krone-6)(CH₃CN)₃][SbCl₆]₂ und [Pb(15-Krone-5)₂][SbCl₆]₂ . [PbCl(18-crown-6)][SbCl₆] has been prepared in low yield besides [Pb(CH₃)₂(18-crown-6)][SbCl₆]₂ by the reaction of Pb(CH₃)₂Cl₂ with antimony pentachloride in acetonitrile solution in the presence of 18-crown-6, forming pale-yellow crystals. The other two title compounds are formed as colourless crystals by the reaction of PbCl₂ with antimony pentachloride in acetonitrile solutions in the presence of 18-crown-6 and 15-crown-5, respectively. The complexes were characterized by IR spectroscopy and by crystal structure determinations. [PbCl(18-crown-6)][SbCl₆]: Space group P2₁/c, Z = 8, 5 003 observed unique reflections, R = 0.046. Lattice dimensions at - 80°C: a = 1 386.9; b = 1 642.7; c = 2 172.1 pm, β = 92.95°. The lead atom in the cation [PbCl(18-crown-6)]⁺ is surrounded in an almost hexagonal-planar construction by the six oxygen atoms of the crown ether and an axially oriented Cl atom. [Pb(18-crown-6)(CH₃CN)₃][SbCl₆]₂: Space group P1 , Z = 2, 6 128 observed unique reflections, R = 0.076. Lattice dimensions at - 70°C: a = 1 228.0; b = 1 422.9; c = 1 463.2 pm, α = 69.08°; β = 65.71°; γ = 64.51°. In the cation [Pb(18-crown-6)(CH₃CN)₃]²⁺ the lead atom is coordinated by the six oxygen atoms of the crown ether and by the three nitrogen atoms of the acetonitrile molecules. The structure determination is restricted by disorder. [Pb( 15-crown-5)₂][SbCI₆]₂: Space group P6₃/m, Z = 6, 5 857 observed unique reflections, R = 0.059. Lattice dimensions at -70°C: a = b = 2 198.5; c = 1499.4 pm, α = β = 90°, γ = 120°. In the cation [Pb(l5-crown-5)₂]² the lead atom is sandwich-like coordinated by the ten oxygen atoms of the two crown ether molecules. The structure determination is restricted by disorder.     

Synthesis and crystal structure of aqua(dibenzo-18-crown-6)potassium (dibenzo-18-crown-6)-(tetrachlorocuprato(II)-Cl)potassium

New mixed complex compound aqua(dibenzo-18-crown-6)potassium (dibenzo-18-crown-6)(tetrachlorocuprato(II)-Cl)potassium, [K(CuCl₄)(Db18C6)]^? · [K(Db18C6)(H₂O)]⁺, is synthesized and its crystal structure is studied by the method of x-ray structural analysis. The structure includes two independent complex ions, both of guest-host type: two cations K⁺ are located in the respective cavities of the Db18C6 crown-ligand (one in each) and each is coordinated by all its six O atoms and one Cl atom of the anion-ligand [CuCl₄]^2? or O atom of the ligand water molecule. Coordination of these two K⁺ cations is completed to hexagonal pyramidal one by formation by each of unusually weak coordination bond K⁺ → π(\(C\dddot - C\)) with two C atoms of respective benzene ring in the neighboring Db18C6 ligand. In this crystal structure the complex anions and cations form dual infinite chains via these coordination bonds and interionic O-H?Cl hydrogen bonds.     

Dibenzo-18-crown-6 diaqua(dibenzo-18-crown-6)potassium triiodide: Synthesis and crystal structure

A new compound, dibenzo-18-crown-6 diaqua(dibenzo-18-crown-6)potassium triiodide [K(Db18C6)(H₂O)₂)⁺ · I₃⁻ · Db18C6 (I), is synthesized and studied by X-ray crystallography. The crystals of compound I are orthorhombic: a = 22.065 ?, b = 22.140 ?, c = 9.433 ?, Z = 4, space group Pccn. Structure I is solved by a direct method and refined by the full-matrix least-squares method in the anisotropic approximation to R = 0.098 for all 5974 unique reflections. Structure I contains the following asymmetric units: a half of the I₃⁻ centrosymmetric anion and two halves of the mixed equally average [K(Db18C6)(H₂O)₂]⁺ host—guest complex cation (a) and a free Db18C6 molecule, each stacked on the axes 2 of the perpendicularly averaged plane of the eighteen-membered macroheterocycle. In complex I, both Db18C6 molecules (a and b) have a “butterfly” conformation with approximate symmetry C _2v . Original Russian Text ? A.N. Chekhlov, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 3, pp. 516–520.     

Halogeno-Nitrosylkomplexe von Molybdän und Wolfram. Die Kristallstrukturen von [Na2(15-Krone-5)2(CH3CN)][MoCl4(NO)2] und [Na(15-Krone-5)]2[MoF4Cl(NO)]

Halogeno-Nitrosyl Complexes of Molybdenum and Tungsten. Crystal Structures of [Na₂(15-Crown-5)₂(CH₃CN)][MoCl₄(NO)₂] and [Na(15-Crown-5)]₂[MoF₄Cl(NO)] MoCl₂(NO)₂ and WCl₂(NO)₂, respectively, react with excess sodium fluoride in acetonitrile at room temperature and in the presence of 15-crown-5 to give crystalline mixtures, which consist of the title compounds, respectively of [Na(15-crown-5)]₂[WCl₄(NO)₂] and [Na(15-crown-5)]₂[WF₄Cl(NO)], and which can be separated by selection. The complexes are characterized by their i.r. spectra, the molybdenum compounds additionally by crystal structure determinations. [Na₂(15-crown-5)₂(CH₃CN)][MoCl₄(NO)₂]: Space group P2₁, Z = 2, 5415 independent unique reflexions, R = 0.039. Lattice dimensions at ?10°C: a = 984.3, b = 1231.1, c = 1483.0 pm, β = 105.67°. The compound consists of cations [Ne(l5-crown-5)(CH₃CN)]⁺, in which the sodium ion is surrounded by the five O-atoms of the crown ether and by the N-atom of the acetonitrile molecule, as well as of anions, which form an ion pair {Na(15-crown-5)[MoCl₄(NO)₂]}^?. In the in pairs the sodium ion is coordinated by the five oxygen atoms of the crown ether and by two chlorine atoms of the [MoCI₄(NO)₂]^2? unit. The nitrosyl ligands take the cis-position a t the molybdenum atom which is in a distorted octahedrally fashion. [Na(15-crown-5)]₂[MoF₄Cl(NO)]. Space group C2/c, Z = 4, 1933 independent unique reflexions, R = 0.078. Lattice dimensions at ?7O°C: D : 1.585.8, b = 1171.5, c = 1771.5 pm, β = 114.91°. The compound forms an ion triple, in which the sodium ions are linked to five oxygen atoms each of the crown ether molecules, and to two F-atoms of the [MoF₄Cl(NO)]^2? unit. The F-atom which is arranged in trans-position to the nitrosyl ligand coordinates with both sodium ions; thus an unusual T-shaped arrangement results for this F-atom. The sole terminal F-Atom and the Cl-atom are disordered in two positions.     

Isolated Triiodide and Pentaiodide Anions in the Crystal Structure of [Rb(Dibenzopyridino‐18‐Crown‐6)2]2(I3)(I5)

Red shiny crystals of [Rb(dibenzopyridino‐18‐crown‐6)₂]₂(I₃)(I₅) were obtained from a dichloromethane/ethanol solution of RbI, I₂ and dibenzopyridino‐18‐crown‐6. Triclinic, , a = 1494.3(1), b = 1534.1(1), c = 2412.9(2) pm, α = 76.95(1), β = 83.58(1), γ = 68.67(1)°, V = 5016.7(7) 10⁶·pm³, Z = 2. The crystal structure consists of [Rb(dbp18c6)₂]⁺ cations leaving suitable three‐dimensional channels for the linear I₃⁻ and V‐shaped I₅⁻ anions which are isolated from each other.     

Copper(II) thiocyanide complexes extractable with [dibenzo-18-crown-6-K] + in chloroform

Summary Cu^II can be extracted from aqueous KSCN solutions using 2,3,11,12-dibenzo-1,7,10,13,16-hexaoxacyclooctadiene (di-benzo-18-crown-6) in CHCl₃. Raman and i.r. spectroscopies establish that the species present in the organic phase after extraction corresponds to [Cu₂OH(SCN)₅]-[dibenzo-18-crown-6-K ⁺]₂, where the Cu^II thiocyanide complex and the K⁺ crown complex are ionically associated.     

Synthese und Charakterisierung von Aquapentachloroplatinaten(IV) – Struktur von [K(18-Krone-6)][PtCl5(H2O)]

Synthesis and Characterization of Aquapentachloroplatinates(IV) – Structure of [K(18-crown-6)][PtCl₅(H₂O)] The crown ether complex of the aquapentachloroplatinic acid of the composition [H₁₃O₆][PtCl₅(H₄O₂)] · 2(18-cr-6) ( 2 ) reacts with K₂CO₃ and [NⁿBu₄]OH in aqueous solution to give [K(18-cr-6)][PtCl₅(H₂O)] ( 5 a ) and [NⁿBu₄][PtCl₅(H₂O)] · ¹/₂ (18-cr-6) · H₂O ( 5 b ), respectively. Both compounds were characterized by microanalysis, vibrational (IR, Raman) and NMR (¹H, ¹³C, ¹⁹⁵Pt) spectroscopy. The X-ray structure analysis of 5 a (orthorhombic, pnma; a = 16,550(4), b = 18,044(3), c = 7,415(1) Å; Z = 4; R1 = 0,0183; wR2 = 0,0414) reveals that the crystal is threaded by chains built up of [PtCl₅(H₂O)]^? and [K(18-cr-6)]⁺ units. There are tight K …? Cl contacts (d(K? Cl1)) = 3,0881(9) Å and O_W? H? O_cr hydrogen bridges (d(O1 …? O2) = 2,806(3) Å) between these units. The coordination polyhedron [PtCl₅O] has approximately C_4v symmetry.     

Synthese und Kristallstrukturen der Seltenerd-Komplexe [LaI2(THF)5]+I3−, [SmCl3(THF)4], [ErCl2(THF)5]+ [ErCl4(THF)2]−, [ErCl3(DME)2] und [Na(18-Krone-6)(THF)2]+ [YbBr4(THF)2]−

Syntheses and Crystal Structures of the Rare-Earth Complexes [LaI₂(THF)₅]⁺I₃^?, [SmCl₃(THF)₄], [ErCl₂(THF)₅]⁺ [ErCl₄(THF)₂]^?, [ErCl₃(DME)₂], and [Na(18-Crown-6)(THF)₂]⁺[YbBr₄(THF)₂]^? [LaI₂(THF)₅]⁺I₃^? ( 1 ) is obtained as red crystals from lanthanum powder and 1,2-diiodoethane in THF on exposure to light. Space group Pbcn, Z = 4, lattice dimensions at ?83°C: a = 1264.9, b = 2218.9, c = 1199.1 pm, R = 0.031. The lanthanum atom of the cation of 1 is coordinated with iodine atoms in the axial positions in a pentagonal-bipyramidal way. [SmCl₃(THF)₄] ( 2 ) originates as colourless crystals on heating SmCl₃ with excess THF in the presence of Me₃SiNPEt₃. Space group P2₁/c, Z = 8, lattice dimensions at ?50°C: a = 3092.7, b = 826.2, c = 1758.3 pm, β = 93.85°, R = 0.054. Just like the known sample that crystallizes within the space group F2dd, 2 forms monomeric molecules in which the samarium atom is coordinated with two chlorine atoms in the axial positions in a distorted pentagonal-bipyramidal way. [ErCl₂(THF)₅]⁺[ErCl₄(THF)₂]^? ( 3 ). Pale pink single crystals of 3 were prepared according to the described method by reaction of erbium powder with trimethylchlorosilane and methanol in THF. Space group C2/c, Z = 4, lattice dimensions at ?50°C: a = 1246.3, b = 1145.7, c = 2726.0 pm, β = 91.293°, R = 0.036. The erbium atom of the cation of 3 has a pentagonal-bipyramidal coordination with the chlorine atoms in the axial positions. Within the anion the THF molecules are in trans-arrangement of the octahedrally coordinated erbium atom. [ErC1₃(DME)₂] ( 4 ) originates as pink single crystals from ₃ with excess boiling 1,2-dimethoxyethane. Space group P2₁/c, Z = 4, lattice dimensions at ?50°C: a = 1137.2, b = 886.5, c = 1561.1 pm, β = 104.746°, R = 0.032. 4 forms monomeric molecules in which the erbium atom has a pentagonal-bipyramidal surrounding with two chlorine atoms in the axial positions. [Na(18-Krone-6)(THF)₂]⁺ [YbBr₄(THF)₂]^? ( 5 ) is formed as by-product by the reaction of YbBr₃ with NaN(SiMe₃)₂ in THF in the presence-of 18-crown-6 forming colourless crystals. Space group P1 , Z = 1, lattice dimensions at ?70°C: a = 934.6, b = 988.9, c = 1208.0 pm, α = 73.82°, β = 72.98°, γ = 76.89°, R = 0.029. 5 contains isolated [YbBr₄(THF)₂]^?ions, in which the THF molecules are arranged in trans-position.     

Crystal and molecular structure of (NH4)2[UO2(NO3)4] and [(NH4)(18C6)]2[UO2(NO3)4]

Single crystals of diammonium tetranitratouranylate (NH₄)₂[UO₂(NO₃)₄] (I) and a new diammonium tetranitratouranylate complex with 18-crown-6 [(NH₄)(18C6)]₂[UO₂(NO₃)₄] (II) have been synthesized by the reaction of diaquadinitratouranyl tetrahydrate with ammonium nitrate in a nitric acid solution and the reaction of the same reagents with 18C6 in an ethanol solution, respectively. The X-ray diffraction analysis of compounds I and II has been performed. Crystals of compounds I and II are monoclinic, Z = 2, space group P2₁/n, a = 6.4075(5) ?, b = 7.7851(7) ?, c = 12.4461(12) ?, β = 101.239(1)°, V = 608. 94(9) ?³ for compound I and a = 10.542(9) ?, b = 8.590(8) ?, c = 22.5019(19) ?, β = 101.632(1)°, V = 2058.3(3) ?³ for compound II. The [UO₂(NO₃)₄]²⁻ complex anion in compounds I and II contains two monodentate and two bidentate cyclic nitrato groups, and the coordination number of uranyl is 6. The 18C6 molecule in the structure of compound II has the classic crown conformation and combined with the ammonium ion by three hydrogen bonds. Compounds I and II formed by electrostatic attraction forces between counterions are stabilized by (NH₄⁺)NH...O(NO₃⁻) interionic hydrogen bonds.     

Synthesis and crystal structure of bis[(18-crown-6)oxonium]tetrabromomanganese(II)

A new complex compound, bis[(18-crown-6)oxonium]tetrabromomanganese(II), 2[(H₃O)⁺(18-crown-6)]·[MnBr₄]^2–, was prepared and studied by X-ray diffraction to reveal its unusual cubic crystal structure, space group Fd $ \bar 3 A new complex compound, bis[(18-crown-6)oxonium]tetrabromomanganese(II), 2[(H₃O)⁺(18-crown-6)]·[MnBr₄]^2–, was prepared and studied by X-ray diffraction to reveal its unusual cubic crystal structure, space group Fd, a 20.424 ?, and Z 8. In this crystal structure, the complex cation [(H₃O)⁺(18-crown-6)] the point symmetry position and the anion [MnBr₄]²⁻ with the point symmetry 23. The complex cation [(H₃O)⁺(18-crown-6)] has a guest-host structure, and, unlike metal complexes by hydrogen bonds between H₃O⁺ hydrogens and 18-crown-6 oxygens, rather than by coordination bonds. The pyramidal cation H₃O⁺ in this crystal structure is statistically disordered, and the tetrahedral anion [MnBr₄]²⁻ is reorientationally disordered. Original Russian Text ? A.N. Chekhlov, 2008, published in Zhurnal Obshchei Khimii, 2008, vol. 78, No. 10, pp. 1622–1626.     

Gold(I) and Gold(III) Trifluoromethyl Derivatives

Trifluoromethylation of AuCl₃ by using the Me₃SiCF₃/CsF system in THF and in the presence of [PPh₄]Br proceeds with partial reduction, yielding a mixture of [PPh₄][Au^I(CF₃)₂] ( 1′ ) and [PPh₄][Au^III(CF₃)₄] ( 2′ ) that can be adequately separated. An efficient method for the high‐yield synthesis of 1′ is also described. The molecular geometries of the homoleptic anions [Au^I(CF₃)₂]^? and [Au^III(CF₃)₄]^? in their salts 1′ and [NBu₄][Au^III(CF₃)₄] ( 2 ) have been established by X‐ray diffraction methods. Compound 1′ oxidatively adds halogens, X₂, furnishing [PPh₄][Au^III(CF₃)₂X₂] (X=Cl ( 3 ), Br ( 4 ), I ( 5 )), which are assigned a trans stereochemistry. Attempts to activate C? F bonds in the gold(III) derivative 2′ by reaction with Lewis acids under different conditions either failed or only gave complex mixtures. On the other hand, treatment of the gold(I) derivative 1′ with BF₃?OEt₂ under mild conditions cleanly afforded the carbonyl derivative [Au^I(CF₃)(CO)] ( 6 ), which can be isolated as an extremely moisture‐sensitive light yellow crystalline solid. In the solid state, each linear F₃C‐Au‐CO molecule weakly interacts with three symmetry‐related neighbors yielding an extended 3D network of aurophilic interactions (Au???Au=345.9(1) pm). The high $\tilde \nu $ _CO value (2194 cm^?1 in the solid state and 2180 cm^?1 in CH₂Cl₂ solution) denotes that CO is acting as a mainly σ‐donor ligand and confirms the role of the CF₃ group as an electron‐withdrawing ligand in organometallic chemistry. Compound 6 can be considered as a convenient synthon of the “Au^I(CF₃)” fragment, as it reacts with a number of neutral ligands L, giving rise to the corresponding [Au^I(CF₃)(L)] compounds (L=CNtBu ( 7 ), NCMe ( 8 ), py ( 9 ), tht ( 10 )).