Neue Gold‐Selen‐Komplexverbindungen: Synthesen und Strukturen von [Au10Se4(dpppe)4]Br2, [Au2Se(dppbe)]∞, [(Au3Se)2(dppbp)3]Cl2 und [Au34Se14(tpep)6(tpepSe)2]Cl6

Novel Gold Selenium Complexes: Syntheses and Structures of [Au₁₀Se₄(dpppe)₄]Br₂, [Au₂Se(dppbe)]_∞, [(Au₃Se)₂(dppbp)₃]Cl₂, and [Au₃₄Se₁₄(tpep)₆(tpep^Se)₂]Cl₆ The reaction of gold phosphine complexes [(AuX)(PR₃)] (X= halogen; R = org. group) with Se(SiMe₃)₂ yield to new chalcogeno bridged gold complexes. Especially within the use of polydentate phosphine ligands cluster complexes like [Au₁₀Se₄(dpppe)₄]Br₂ ( 1 ) (dpppe = 1, 5‐Bis(diphenylphosphino)pentane), [Au₂Se(dppbe)]_∞ ( 2 ) (1, 4‐Bis(diphenylphosphino)benzene), [(Au₃Se)₂(dppbp)₃]Cl₂ ( 3 ) (dppbp = 4, 4′‐Bis‐diphenylphosphino)biphenyl) und [Au₃₄Se₁₄(tpep)₆(tpep^Se)₂]Cl₆ ( 4 ) (tpep = 1, 1, 1‐Tris(diphenylphosphinoethyl)phosphine, tpep^Se = 1, 1‐Bis(diphenylphosphinoethyl)‐1‐(diphenylselenophosphinoethylphosphine) could be isolated and their structures could be determined by X‐ray diffraction. ( 1: Space group P1 (No. 2), Z = 2, a = 1642.1(11), b = 1713.0(9), c = 2554.0(16) pm, α = 80.41(3)°, β = 76.80(4)°, γ = 80.92(4)°; 2: Space group P2₁/n (No. 14), Z = 4, a = 947.3(2), b = 1494.9(3), c = 2179.6(7) pm, β = 99.99(3)°; 3: Space group P2₁/c (No. 14), Z = 8, a = 2939.9(6), b = 3068.4(6), c = 3114.5(6) pm, β = 109.64(3)°; 4: Space group P1 (No. 2), Z = 1, a = 2013.7(4), b = 2420.6(5), c = 2462.5(5) pm, α = 77.20(3), β = 74.92(3), γ = 87.80(3)°).     

Reaction of Selenium with Bromine in the Presence of Methyltriphenylphosphonium Bromide: Syntheses and Crystal Structures of [PMePh3]2[Se2Br6] and [PMePh3]2[SeBr6(SeBr2)2]

The brown crystals of [PMePh₃]₂[Se₂Br₆] ( 1 ) and red crystals of [PMePh₃]₂[SeBr₆(SeBr₂)₂] ( 2 ) were obtained when selenium and bromine reacted in the solution of acetonitrile in the presence of methyltriphenylphosphonium bromide. The crystal structures of 1 and 2 has been determined by the X‐ray methods and refined to R = 0.0373 for 2397 reflections and 0.0397 for 3417 reflections, respectively. The salt 1 crystallizes in the monoclinic space group P2₁/n with the cell dimensions a = 13.202(5) Å, b = 11.954(4) Å, c = 13.418(6) Å, β = 93.08(4)° (193(2)). The crystals of 2 are triclinic, space group with the cell dimensions a = 10.266(3) Å, b = 11.311(3) Å, c = 11.619(2) Å, α = 108.87(2)°, β = 105.72(2)°, γ = 99.40(2)° (193(2) K). In the solid state structure of 1 the dinuclear hexabromo‐diselenate(II) anion is centrosymmetric and consists of two distorted almost square planar SeBr₄ units sharing a common edge through two μ‐bridging Br atoms. The terminal Se^II–Br bonds are 2.3984(11) and 2.4273(11) Å, whereas the bridging μBr–Se^II bonds are 2.7817(11) and 2.9081(12) Å. In the solid state the trinuclear [SeBr₆(SeBr₂)₂]^2? anion of 2 is centrosymmetric too and contains a nearly regular [SeBr₆] octahedron where the four equatorial bromo ligands each have developed bonds to the Se^II atoms of the SeBr₂ molecules. The contacts between the bridging bromo and the Se^II atoms of the SeBr₂ molecules are 3.0603(15) and 3.1043(12) Å, and can be interpreted as bonds of the donor‐acceptor type with the bridging bromo ligands as donors and the SeBr₂ molecules as acceptors. The Se^IV–Br distances are in the range 2.5570(9)–2.5773(11) Å and the Se^II–Br bond lengths in coordinated SeBr₂ molecules – 2.3411(12) and 2.3421(10) Å.     

Synthesis and Crystal Structure of Tetrakis(tetramethylammonium) Bis[decabromotetraselenate(II)]‐bis[dibromodiselenate(I)], [(CH3)4N]4[(Se4Br10)2(Se2Br2)2], the Salt of a Mixed‐Valence Bromoselenate(II/I) Anion

Brown crystals of [NMe₄]₄[(Se₄Br₁₀)₂(Se₂Br₂)₂] ( 1 ) were obtained from the reaction of selenium and bromine in acetonitrile in the presence of tetramethylammonium bromide. The crystal structure of 1 was determined by X‐ray diffraction and refined to R = 0.0297 for 8401 reflections. The crystals are monoclinic, space group P2₁/c with Z = 4 and a = 12.646(3) Å, b = 16.499(3) Å, c = 16.844(3) Å, β = 101.70(3)° (123 K). In the solid‐state structure, the anion of 1 is built up of two [Se₄Br₁₀]^2– ions. Each shows a triangular arrangement of three planar SeBr₄ units sharing a common edge through two μ₃‐bridging bromine atoms, and one SeBr₂ molecule, which is linked to the Se^II atoms of two SeBr₄ units; between the Se₄Br₁₀^2– ions a dimerized Se₂Br₂ molecule (Se₄Br₄) is situated and one Se^I atom of each Se₂Br₂ molecule has two weak contacts [3.3514(14) Å and 3.3952(11) Å] to two bromine atoms of one SeBr₄ unit. Four Se^I atoms of a dimerized Se₂Br₂ molecule are in a almost regular planar tetraangular arrangement. Contacts between the Se^II atom of the SeBr₂ molecule and the Se^II atoms of two SeBr₄ units are 3.035(1) Å and 3.115(1) Å, and can be interpreted as donor‐acceptor type bonds with the Se^II atoms of SeBr₄ units as donors and the SeBr₂ molecule as acceptor. The terminal Se^II–Br and μ₃‐Br–Se^II bond lengths are in the ranges 2.3376(10) to 2.4384(8) Å and 2.8036(9) to 3.3183(13) Å, respectively. The bond lengths in the dimerized Se₂Br₂ molecule are: Se^I–Se^I = 2.2945(8) Å and 3.1398(12), Se^I–Br = 2.3659(11) and 2.3689(10) Å.     

Synthesis and Crystal Structure of >Bis(tetrapropylammonium) Hexabromotellurate(IV)‐bis{dibromoselenate(II)}, [NnPr4]2[TeBr6(SeBr2)2], the Salt of a Mixed‐valence Bromotellurate(IV)‐Selenate(II) Anion

Dark brown crystals of [NⁿPr₄]₂[TeBr₆(SeBr₂)₂] ( 1 ) were obtained when selenium and bromine (1:1) were allowed to react in acetonitrile solution in the presence of tellurium(IV) bromide and tetrapropylammonium bromide. The salt 1 crystallizes in the monoclinic space group P2₁/n with the cell dimensions a = 14.7870(3) Å, b = 9.5523(3) Å, c = 16.7325(3) Å, β = 110.56(10)° (at 123(2) K). In the solid state the [TeBr₆(SeBr₂)₂]^2– anion contains a nearly regular [TeBr₆] octahedron in which the four equatorial bromo ligands have developed bonds to Se^II atoms of the SeBr₂ molecules. The contacts between the bridging bromo and the Se^II atoms of the SeBr₂ molecules are 3.0000(4) and 3.0561(4) Å, and can be interpreted as bonds of the donor‐acceptor type with the bridging bromo ligands as donors and the SeBr₂ molecules as acceptors. The Te^IV–Br distances are in the range 2.6816(3)–2.7131(3) Å and the Se^II–Br bond lengths in the coordinated SeBr₂ molecules are 2.3548(4) and 2.3725(4) Å.     

Synthesis and Crystal Structure of Bis(methyltriphenylphosphonium) Hexabromotellurate(IV)‐bis{dibromoselenate(II)}, [PMePh3]2[TeBr6(SeBr2)2], the Salt of a Mixed‐valence Bromotellurate(IV)‐Selenate(II) Anion

Brown crystals of [PMePh₃]₂[TeBr₆(SeBr₂)₂] ( 1 ) were obtained when selenium and bromine (1:1) react in acetonitrile solution in the presence of tellurium(IV) bromide and methyltriphenylphosphonium bromide. The salt 1 crystallizes in the triclinic space group P1¯ with the cell dimensions a = 10.3630(14)Å, b = 11.5140(12)Å, c = 11.7605(17)Å, α = 108.643(9)°, β = 106.171(10)° and γ = 99.077(9)° (296 K). In the solid state the [TeBr₆(SeBr₂)₂]^2— anion contains a nearly regular [TeBr₆] octahedron where the four equatorial bromo ligands each have developed a bond to the Se^II atom of a SeBr₂ molecule. The contacts between the bridging bromo and the Se^II atoms of the SeBr₂ molecules are observed in the range 3.11—3.21Å, and can be interpreted as bonds of the donor‐acceptor type with the bridging bromo ligands as donors and the SeBr₂ molecules as acceptors. The Te^IV—Br distances are in the range 2.67—2.72Å, and the Se^II—Br bond lengths in coordinated SeBr₂ molecules in the range 2.33—2.34Å.     

Synthesis and Structural Characterization of [Cu20Se4(μ3‐SePh)12(PPh3)6] and [Ag(SePh)]∞

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 [Cu₂₀Se₄ (μ₃‐SePh)₁₂(PPh₃)₆] ( 1 ). The analogous reaction with AgCl yields the extended structure [Ag(SePh)]_∞ ( 2 ) in which an infinite layer of Ag^I 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)°.     

(Se4)2[Mo2O2Cl8][MCl6](M = Zr,Hf) — Tetraselenium(2+)Halometalates with two Different Anions

The reaction of Se₄[Mo₂O₂Cl₈] with Se₄[MCl₆] (M = Zr, Hf) or of Se, SeCl₄, MoOCl₄, and MCl₄ (M = Zr, Hf) at 120 °C in sealed evacuated glass ampoules gives (Se₄)₂[Mo₂O₂Cl₈][MCl₆] (M = Zr, Hf) in the form of dark‐green, air sensitive crystals in quantitative yield. The crystal structure analyses of both isotypic compounds (monoclinic, P2₁/c, Z = 2, a = 1336(2), b = 716(1), c = 1518(4) pm, β = 106.0(2)° for M = Zr; a = 1334.1(8), b = 715.03(9), c = 1518.2(3) pm, β = 106.00(2)° for M = Hf) show the presence of square‐planar Se₄²⁺, of dinuclear [Mo₂O₂Cl₈]^2—, and of almost regular octahedral [MCl₆]^2— ions. X‐ray crystallographic investigations on (Se₄)₂[Mo₂O₂Cl₈][ZrCl₆] give no hint for solid state phase transitions between —160 and 200 °C. This is in contrast to the related compounds Se₄[Mo₂O₂Cl₈] and Se₄[ZrCl₆] which both undergo phase transitions accompanied by reorientation of the cations and anions. (Se₄)₂[Mo₂O₂Cl₈][ZrCl₆] is paramagnetic and obeys the Curie‐Weiss law with a Weiss constant of —4(7) K indicating only weak interaction between the paramagnetic centres. The magnetic moment of 1.7(1) μ_B is consistent with the presence of Mo^V (d¹ configuration) and supports the ionic formula.     

Synthese und Kristallstrukturen von (3‐Methylpyridinium)3[DyCl6] und (3‐Methylpyridinium)2[DyCl5(Ethanol)]

Preparation and Structure of (3‐Methylpyridinium)₃[DyCl₆] and (3‐Methylpyridinium)₂[DyCl₅(Ethanol)] The complex chlorides (3‐Methylpyridinium)₃[DyCl₆] ( 1 ) and (3‐Methylpyridinium)₂[DyCl₅(Ethanol)] ( 2 ) have been prepared for the first time. The crystal structures have been determined from single crystal X‐ray diffraction data. 1 crystallizes in the trigonal space group R3c (Z = 36) with a = 2953.3(3) pm, b = 2953.3(3) pm and c = 3252.5(4) pm, compound 2 crystallizes in the triclinic space group P1 (Z = 2) with a = 704.03(8) pm, b = 808.10(8) pm, c = 1937.0(2) pm, α = 77.94(1)°, β = 87.54(1)° and γ = 83.26(1)°. The structures contain isolated octahedral building units [DyCl₆]^3– and [DyCl₅(Ethanol)]^2–, respectively.     

Direct Syntheses of Bis(tetraphenylphosphonium) and Bis(ethyltriphenylphosphonium) Hexabromo‐diselenates(II), [PPh4]2[Se2Br6] and [PEtPh3]2[Se2Br6]. The Crystal Structure of [PEtPh3]2[Se2Br6]

Brown crystals of [PPh₄]₂[Se₂Br₆] ( 1 ) and [PEtPh₃]₂[Se₂Br₆] ( 2 ) were obtained when selenium and bromine reacted in acetonitrile solution in the presence of tetraphenylphosphonium bromide and ethyltriphenylphosphonium bromide, respectively. The crystal structure of 2 has been determined by X‐ray methods and refined to R = 0.0420 for 4161 reflections. The crystals are monoclinic, space group P2₁/n with Z = 2 and a = 13.055(3) Å, b = 12.628(3) Å, c = 13.530(3) Å, β = 92.40(3)° (293(2) K). In the solid state structure of 2 the dinuclear hexabromo‐diselenate(II) anion is centrosymmetric and consists of two distorted almost square‐planar SeBr₄ units sharing a common edge through two bridging Br atoms. The terminal Se^II–Br bond distances are found to be 2.419(1) and 2.445(1) Å, the bridging μBr–Se^II bond distances 2.901(1) and 2.802(1) Å.     

Synthesis and Crystal Structure of Bis(tetraphenylphosphonium) Hexabromo‐diselenate(II)‐bis{dibromodiselenate(I)}, [PPh4]2[Se2Br6(Se2Br2)2], the Salt of a Mixed‐valence Bromoselenate(II,I) Anion

The Red crystals of [PPh₄]₂[Se₂Br₆(Se₂Br₂)₂] ( 1 ) were obtained when selenium and bromine reacted in the solution of acetonitrile in the presence of tetraphenylphosphonium bromide. The crystal structure of 1 has been determined by X‐ray diffraction and refined to R = 0.0201 for 4024 reflections. The crystals are triclinic, space group with Z = 2 and a = 11.2757(4) Å, b = 12.3347(5) Å, c = 12.4948(5) Å, α = 113.152(4)°, β = 114.745(4)°, γ = 91.208(3)° (120(2) K). In the solid state the anion of 1 is built up of the Se₂Br₆ core and two Se₂Br₂ molecules each of which is linked to one of the trans‐positioned terminal Br_t atoms of the Se₂Br₆ core. The central Se₂Br₆ part consists of a nearly planar arrangement of two planar SeBr₄ units sharing a common edge through two μ₂‐bridging Br atoms. The contact between the Br_t and the Se^I atom of the Se₂Br₂ molecule is 3.0872(5) Å and can be interpreted as a bond of the donor‐acceptor type with the Br_t as donor and the Se₂Br₂ molecule as acceptor. The terminal Se^II–Br and μ₂Br–Se^II bond lengths are 2.3654(4), 2.6699(5) Å and 2.5482(5), 3.0265(5) Å, respectively. The bond lengths in the coordinated Se₂Br₂ molecule are: Se^I–Se^I = 2.2686(5) Å, Se^I–Br = 2.3779(5) and 2.3810(5) Å.     

Synthesis and Crystal Structure of Bis(tetraethylammonium) Octabromo‐triselenate(II)‐{dibromodiselenate(I)}, [NEt4]2[Se3Br8(Se2Br2)], the Salt of a Mixed‐valence Bromoselenate(II,I) Anion

The brown crystals of [NEt₄]₂[Se₃Br₈(Se₂Br₂)] ( 1 ) were obtained when selenium and bromine reacted in the solution of acetonitrile in the presence of tetraethylammonium bromide. The crystal structure of 1 has been determined by the X‐ray methods and refined to R = 0.0308 for 10433 reflections. The crystals are monoclinic, space group P2₁ with Z = 2 and a = 12.0393(3) Å, b = 11.8746(3) Å, c = 13.1946(3) Å, β = 96.561(1)° (123 K). In the solid state structure the anion of 1 is built up of Se₃Br₈ unit which consists of a triangular arrangement of three planar SeBr₄ units sharing a common edge through two μ₃‐bridging Br atoms, and one Se₂Br₂ molecule which is linked to one of μ₃‐bridging Br atoms. The three Se^II atoms form a triangle which is almost perpendicular to the planes given by three SeBr₄ moieties. The contact between the μ₃Br and the Se^I atom of the Se₂Br₂ molecule is 3.1711(8) Å and can be interpreted as a bond of the donor‐acceptor type with the μ₃Br as donor and the Se₂Br₂ molecule as acceptor. The terminal Se^II‐Br and μ₃Br‐Se^II bond lengths are in the ranges 2.3537(7)–2.4737(7) Å and 2.7628(7)–3.1701(7) Å, respectively. The bond lengths in coordinated Se₂Br₂ molecule are: Se^I‐Se^I = 2.2636(9) Å, Se^I‐Br = 2.3387(11) and 2.3936(8) Å.     

Synthesen und Strukturen der polymeren Silber‐Komplexe [Ag2Cl2(dppbp)3]∞, [Ag2(SPh)2(dppe)3]∞ und [Ag2(SPh)2(triphos)]∞ sowie der Silber‐Chalkogenido‐Cluster [Ag7(SPh)7(dppm)3], {[Ag7(TePh)7(dppp)3]2(dppp)} und [Ag22Cl(SPh)10(PhCOO)11(dmf)3]∞

Syntheses and Structures of the Polymeric Silver Complexes [Ag₂Cl₂(dppbp)₃]_∞, [Ag₂(SPh)₂(dppe)₃]_∞ and [Ag₂(SPh)₂(triphos)]_∞ as well as the Silver Chalcogenido Clusters [Ag₇(SPh)₇(dppm)₃], {[Ag₇(TePh)₇(dppp)₃]₂(dppp)}, and [Ag₂₂Cl(SPh)₁₀(PhCOO)₁₁(dmf)₃]_∞ The reaction of silver carboxylate with silylated chalcogen compounds have been found to have a possibility for the synthesis of metal‐chalcogenide‐custers. Especially phosphine ligands have been found to be useful in stabilising the cluster cores. Some of the silver carboxylate phosphine complexes, which are formed in‐situ, ([Ag₂Cl₂(dppbp)₃]_∞ ( 1 )) and some silver chalcogen complexes ([Ag₂(SPh)₂(dppe)₃]_∞ ( 2 ) und [Ag₂(SPh)₂(triphos)]_∞ ( 3 )), could be isolated and characterised by X‐ray diffraction. Using special reaction conditions, it is possible to isolate cluster species like [Ag₇(SPh)₇(dppm)₃] ( 4 ), {[Ag₇(TePh)₇(dppp)₃]₂(dppp)} ( 5 ) and [Ag₂₂Cl(SPh)₁₀(PhCOO)₁₁(dmf)₃]_∞ ( 6 ) beside the complex compounds. 1: Space group P2₁/n (No. 14), Z = 2, a = 1336, 1(2), b = 2081, 2(5), c = 2015, 4(4) pm, β = 99, 87(2)°; 2: Space group P2₁/n (No. 14), Z = 2, a = 1416, 1(3), b = 1874, 7(4), c = 1444, 8(3) pm, β = 93, 26(3)°; 3: Space group P2₁/n (No. 14), Z = 4, a = 1456, 8(3, b = 1890, 2(4), c = 1916, 1(4) pm, β = 99, 11(3)°; 4: Space group P2₁/n (No. 14), Z = 4, a = 1570, 2(3), b = 2798, 5(6), c = 2752, 7(6) pm, β = 98, 02(3)°; 5: Space group P1 (No. 2), Z = 2, a = 2115, 5(4), b = 2553, 3(5), c = 3188, 7(6) pm, α = 68, 87(3)°, β = 74, 05(3)°, γ = 69, 70(3)°; 6: Space group P1 (No. 2), Z = 2, a = 1583, 0(3), b = 1709, 6(3), c = 2990, 0(6) pm, α = 80, 41(3)°, β = 88, 86(3)°, γ = 71, 10(3)°).     

Phosphaniminato-Komplexe von Bor. Synthese und Kristallstrukturen von [BBr2(NPMe3)]2, [B2Br3(NPiPr3)2]Br, [B2(NPEt3)4]Br2, [B2Br2(NPPh3)3]BBr4 und [{B2(NMe2)2}2(NPEt3)2]Cl2

Phosphoraneiminato Complexes of Boron. Syntheses and Crystal Structures of [BBr₂(NPMe₃)]₂, [B₂Br₃(NPⁱPr₃)₂]Br, [B₂(NPEt₃)₄]Br₂, [B₂Br₂(NPPh₃)₃]BBr₄ and [{B₂(NMe₂)₂}₂(NPEt₃)₂]Cl The bromoderivatives of the title compounds are prepared from the corresponding silylated phosphoraneimines Me₃SiNPR₃ and boron tribromide. The boron subcompound [{B₂(NMe₂)₂}₂(NPEt₃)₂]Cl₂ derives from Me₃SiNPEt₃ and B₂Cl₂(NMe₂)₂. All complexes are characterized by NMR and IR spectroscopy as well as by crystal structure determinations. [BBr₂(NPMe₃)]₂ (1): Space group P2₁/n, Z = 2, R = 0.031. Lattice dimensions at ?50°C: a = 723.8, b = 894.2, c = 1305.4 pm, β = 92.35°. 1 forms centrosymmetric molecules in which the boron atoms are linked via μ₂-N bridges of the NPMe₃^? groups of from B₂N₂ four-membered rings with B? N distances of 149.9 and 150.9 pm. B₂Br₃(NPⁱPr₃)₂]Br (2): Space group P2₁, Z = 2, R = 0.059. Lattice dimensions at ?80°C: a = 817.6, b = 2198.7, c = 851.5 pm, β = 115.09°. In the cations of 2 the boron atoms are lined via the μ₂-N atoms of the NPⁱPr₃^? groups to form planar, asymmetric B₂N₂ four-membered rings with B? N distances of 143 and 156 pm. [B₂(NPEt₃)₄[Br₂·4CH₂Cl₂ (3): Space group C2/c, Z = 4, R = 0.042. Lattice dimensions at ?50°C: a = 1946.1, b = 1180.3, c = 2311.3 pm, β = 101.02°. The structure contains centrosymmetric dications in which both the boron atoms are lined by the N atoms of two of the NPEt₃^? groups to form a B₂N₂ four-membered ring with B? N distances of 149.6 pm. The remaining two NPEt₃^? groups are terminally bonded with very short B? N distances of 133.5 pm. B₂Br₂(NPPh₃)₃]BBr₄ (4): Space group P1 , Z = 2, R = 0.065. Lattice dimension at ?50°C: a = 1025.7, b = 1496.1, c = 1807.0 pm, α = 85.09°, β = 82.90°, γ = 82.72°. In the cation the boron atoms are lined via the μ₂-N atoms of two of the NPPh₃^? groups to form a nearly planer B₂N₂ four-membered ring with B? N distances of 149.3-153.1 pm. The third NPPh₃³ group is terminally connected with teh sp² hybridized boron atom and with a B? N distance of 134.1 pm along with an almost linear BNP bond angle of 173.6°. [{B₂(NMe₂)₂}₂(NPEt₂)₂]Cl₂ · 3CH₂Cl₂ (5): Space group C2/c, Z = 4, R = 0.098. Lattice dimensions at ?70°C: a = 1557.9, b = 1294.7, c = 2122.9 pm, β = 96.08°. The structure of 4 contains centrosymmetric dications in which two by two B-B dumb-bells are linked via the μ₂-N atoms of the two NEPt₃^? groups to form B₄N₂ six-membered rings with B? N distances of 150 and 156 pm and B-B distances of 173 pm. The B? N distances of the terminally bonded NMe₂^? groups correspond to 138 pm double bonds.     

Competitive Coordination of the Uranyl Ion by Perchlorate and Water ‐ The Crystal Structures of UO2(ClO4)2·3H2O and UO2(ClO4)2·5H2O and a Redetermination of UO2(ClO4)2·7H2O

By slow evaporation of solutions containing UO₂(ClO₄)₂ and an excess of HClO₄, single crystals of [UO₂(ClO₄)₂(H₂O)₃] ( 1 ) and [UO₂(H₂O)₅](ClO₄)₂ ( 2 ) were obtained and their structures were determined. From similar solutions prepared from stoichiometric amounts of UO₃ and perchloric acid, crystals of [UO₂(H₂O)₅](ClO₄)₂·2H₂O ( 3 ) were obtained. The trihydrate (monoclinic, P2₁/c, a = 545.44(1) pm, b = 1811.09(5) pm, c = 1032.46(2) pm, β = 90.016(1)°) consists of uranyl ions, which are coordinated by two monodentate perchlorate ions and three water molecules. The pentahydrate (monoclinic, P2₁/n, a = 529.35(2) pm, b = 1645.43(6) pm, c = 1480.18(6) pm, β = 99.847(1)°) contains uranyl ions coordinated by five water molecules. The same structural unit can be found in the heptahydrate, whose structure was re‐determined (orthorhombic, Pbcn, a = 920.9(3) pm, b = 1067.9(3) pm, c = 1445.7(3) pm). In this structure, two molecules of water of crystallization are present.     

Synthese und Kristallstrukturen von (2‐Methylpyridinium)3[TbCl6] und (2‐Methylpyridinium)2[TbCl5(1‐Butanol)]

Preparation and Structure of (2‐Methylpyridinium)₃[TbCl₆] and (2‐Methylpyridinium)₂[TbCl₅(1‐Butanol)] The complex chlorides (2‐Methylpyridinium)₃[TbCl₆] (1) and (2‐Methylpyridinium)₂[TbCl₅(1‐Butanol)] (2) have been prepared for the first time. The crystal structures have been determinated from single crystal X‐ray diffraction data. 1 crystallizes in the monoclinic space group C2/c (Z = 8) with a = 3241,2(5) pm, b = 897,41(9) pm, c = 1774,2(2) pm and β = 97,83(2)°, 2 in the monoclinic space group P2₁/n (Z = 4) with a = 1372,96(16) pm, b = 997,57(9) pm, c = 1820,5(2) pm and β = 108,75(1)°. The structures contain isolated octahedral building units [TbCl₆]^3– and [TbCl₅(1‐Butanol)]^2–, respectively.     

Rare Earth Carbodiimide Silicates: RE2(CN2)(SiO4)

Rare earth carbodiimide silicates RE₂(CN₂)(SiO₄) with RE = Y, La, and Pr were synthesised by solid state metathesis reactions of RECl₃, Li₂(CN₂), and SiO₂ or Li₂SiO₄, respectively, in silica tubes at 550 °C. All three compounds crystallise with different structures, although all of them represent distorted derivatives of the sodium chloride type structure. The structure of Y₂(CN₂)(SiO₄) was refined monoclinically (C2/m, Z = 2, a = 1301.382(5) pm, b = 377.630(1) pm, c = 527.656(2) pm, β = 93.9816(2) °) from X‐ray powder data. The crystal structure of La₂(CN₂)(SiO₄) was refined in a different monoclinic space group (P2₁/c, Z = 4, a = 660.3(1) pm, b = 1282.0(2) pm, c = 656.2(1) pm, β = 105.23(2) °), and the structure of Pr₂(CN₂)(SiO₄) was refined triclinically (P\bar{1} , Z = 2, a = 646.7(2) pm, b = 669.2(2) pm, c = 671.8(2) pm, α = 86.18(3) °, β = 73.22(3) °, γ = 74.08(3) °) from X‐ray single crystal data.     

Ortho‐Chalcogenotetrelate Anions as Chelating Ligands: Syntheses and Characterization of [K6(MeOH)9][Sn2Se6][Cr(en)2(SnSe4)]2, [Na(H2O)4][Cr(en)3]2[GeS3OH]2[Cr(en)2(GeS4)], and [Ba(H2O)10][{Cr(en)}2(GeSe4)2]

Reactions of K₄[SnSe₄], Na₄[GeS₄] or Ba₂[GeSe₄] with different 1,2‐diaminoethane (= en) coordinated complexes of CrCl₃ ([Cr(en)₂Cl₂]Cl or [Cr(en)₃]Cl₃) in MeOH or aqueous solution yielded three novel compounds that contain complexes of Cr³⁺ with ortho‐chalcogenotetrelate anions [E′E₄]^4? (E′ = Ge, Sn; E = S; Se): the crystal structures of [K₆(MeOH)₉][Sn₂Se₆][Cr(en)₂(SnSe₄)]₂ ( 1 ), [Na(H₂O)₄][Cr(en)₃]₂[GeS₃OH]₂[Cr(en)₂(GeS₄)] ( 2 ), and [Ba(H₂O)₁₀][{Cr(en)}₂(GeSe₄)₂] ( 4 ) have been determined by means of single crystal X‐ray diffraction ( 1 : triclinic space group ; lattice dimensions at 203 K: a = 1175.7(2), b = 1315.3(3), c = 1326.7(3) pm, α = 61.99(3)°, β = 64.05(3)°, γ = 83.57(3)°, V = 1617.4(6)·10⁶ pm³; R₁ [I > 2σ(I)] = 0.0788; wR₂ = 0.1306; 2 : monoclinic space group C2/c; lattice dimensions at 203 K: a = 2445.3(5), b = 1442.5(3), c = 1579.3(3) pm, β = 94.61(3)°, V = 5552.9(19)·10⁶ pm³; R₁ [I > 2σ(I)] = 0.0801; wR₂ = 0.2046; 4 : triclinic space group ; lattice dimension at 203 K: a = 1198.4(2), b = 1236.8(3), c = 1297.5(3) pm, α = 65.69(3)°, β = 63.35(3)°, γ = 81.21(3)°, V = 1565.2(5)·10⁶ pm³; R₁ [I > 2σ(I)] = 0.0732; wR₂ = 0.1855). 1 and 2 show the yet unprecedented complexation of transition metal ions by non‐bridging, single chalcogenotetrelate ligands to produce dinuclear, heterobimetallic complexes. Compound 2 contains the first structurally characterized complex with an ortho‐thiogermanate ligand. The formation of these compounds, and of a by‐product of 2 , [Cr(en)₃][GeS₃OH]·6H₂O ( 3 : monoclinic space group C2/c; lattice dimensions at 203 K: a = 2396.8(5), b = 1463.4(3), c = 1740.1(4) pm, β = 132.99(3)°, V = 4463.8(15)·10⁶ pm³; R₁ [I > 2σ(I)] = 0.0462; wR₂ = 0.1058), provides some insight in fundamental differences between the reaction behavior of [SnE₄]^4? anions one the one hand and [GeE₄]^4? anions on the other hand. The crucial role of the counterion charge becomes evident when comparing the structure motifs of the ternary anions in 1 and 2 with that observed in the Ba²⁺ compound 4 .     

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.     

Selen‐Polykationen stabilisiert durch polymere Chlorobismutat‐Anionen: Synthesen und Kristallstrukturen von Se4[Bi4Cl14] und Se10[Bi5Cl17]

Selenium Polycations Stabilized by Polymeric Chlorobismuthate Anions: Syntheses and Crystal Structures of Se₄[Bi₄Cl₁₄] and Se₁₀[Bi₅Cl₁₇] Reactions of selenium with selenium(IV) chloride and bismuth(III) chloride in sealed evacuated glass ampoules at temperatures between 110 and 155 °C yield a series of compounds which are composed of discrete selenium polycations and polymeric chlorobismutate anions. Besides the already known Se₈[Bi₄Cl₁₄] two new compounds have been identified by crystal structure analyses as Se₄[Bi₄Cl₁₄] (tetragonal, P4/n, a = 1089.1(2) pm, c = 993.7(2) pm, Z = 2) and Se₁₀[Bi₅Cl₁₇] (monoclinic, P2₁/c, a = 1079.24(8) pm, b = 2062.9(2) pm, c = 1676.1(2) pm, β = 90.87(1)°, Z = 4). Se₄[Bi₄Cl₁₄] was obtained as red transparent platelike crystals and is the first example of a compound with (chalcogen₄)²⁺ ions of exact square‐planar symmetry and molecular point group D_4h in the solid state. The cations are surrounded by layers of two‐dimensional polymeric anions [Bi₄Cl₁₄]^2–. Se₁₀[Bi₅Cl₁₇] forms dark grey crystals with a reddish luster. The structure contains the known bicyclic polycation Se₁₀²⁺ which is disordered over two positions and the first three‐dimensional polymeric chlorobismutate anion [Bi₅Cl₁₇]^2–. The different BiCl_x polyhedra are linked by sharing common vertices, edges, and faces.     

Low‐Dimensional Structural Units in Amine‐Templated Uranyl Oxoselenates(VI): Synthesis and Crystal Structures of [C3H12N2][(UO2)(SeO4)2(H2O)2](H2O), [C5H16N2]2[(UO2)(SeO4)2(H2O)](NO3)2, [C4H12N][(UO2)(SeO4)(NO3)], and [C4H14N2][(UO2)(SeO4)2(H2O)]

The crystals of four amine‐templated uranyl oxoselenates(VI), [C₃H₁₂N₂][(UO₂)(SeO₄)₂(H₂O)₂](H₂O) ( 1 ), [C₅H₁₆N₂]₂[(UO₂)(SeO₄)₂(H₂O)](NO₃)₂ ( 2 ), [C₄H₁₂N][(UO₂)(SeO₄)(NO₃)] ( 3 ), and [C₄H₁₄N₂][(UO₂)(SeO₄)₂(H₂O)] ( 4 ) were prepared by evaporation from aqueous solution of uranyl nitrate, selenic acid and the respective amine. The crystal structures of all four compounds have been solved by direct methods from X‐ray diffraction data. The structure of 1 (triclinic, , a = 7.5611(16), b = 7.7650(17), c = 12.925(3) Å, α = 94.605(18), β = 94.405(17), γ = 96.470(17)°, V = 748.8(3) ų, R₁ = 0.029 for 2769 unique observed reflections) is based upon 0D‐units of the composition [(UO₂)₂(SeO₄)₄(H₂O)₄]^4?. These discrete units are composed from two pentagonal [UO₇]^8? bipyramids linked via [SeO₄]^2? tetrahedra and are unknown in structural chemistry of uranium so far. The structure of 2 (monoclinic, C2/c, a = 28.916(5), b = 8.0836(10), c = 11.9856(16) Å, β = 110.909(11)°, V = 2617.1(6) ų, R₁ = 0.035 for 2578 unique observed reflections) contains [(UO₂)(SeO₄)₂(H₂O)]^2? chains of corner‐sharing pentagonal [UO₇]^8? bipyramids and [SeO₄]^2? tetrahedra. The chains run parallel to the c axis and are arranged into layers parallel to (100). In the structure of 3 (monoclinic, C2/m, a = 21.244(5), b = 7.1092(11), c = 8.6581(18) Å, β = 97.693(17)°, V = 1295.8(4) ų, R₁ = 0.027 for 1386 unique observed reflections), pentagonal [UO₇]^8? bipyramids share corners with three [SeO₄]^2? tetrahedra each and an edge with a [NO₃]^? anion to form [(UO₂)(SeO₄)(NO₃)]^? chains parallel to the b axis. In the structure of 4 (triclinic, , a = 6.853(2), b = 10.537(3), c = 10.574(3) Å, α = 99.62(3), β = 94.45(3), γ = 100.52(3)°, V = 735.6(4) ų, R₁ = 0.045 for 2713 unique observed reflections), one symmetrically independent pentagonal [UO₇]^8? bipyramid shares corners with four [SeO₄]^2? tetrahedra to form the [(UO₂)(SeO₄)₂(H₂O)]^2? chains parallel to the a axis. A comparison to related uranyl compounds is given.