Die Kristallstrukturen von [Et3PNAsPh3]2[Ag2Br4] und [Et3PNAsPh3]2[Pd2Br6]

Crystal Structures of [Et₃PNAsPh₃]₂[Ag₂Br₄] and [Et₃PNAsPh₃]₂[Pd₂Br₆] Colourless single crystals of [Et₃PNAsPh₃]₂[Ag₂Br₄]( 1 ) and red single crystals of [Et₃PNAsPh₃]₂[Pd₂Br₆]( 2 ) have been isolated from saturated solutions in acetonitrile of equivalent mixtures of [Et₃PNAsPh₃]Br with AgBr and PdBr₂, respectively. Both complexes were characterized by IR spectroscopy and by crystal structure determinations. 1 : Space group P1¯, Z = 1, lattice dimensions at ‐70°C: a = 985.0(2), b = 1042.2(5), c = 1345.8(5) pm, α = 102.88(2)°, β = 105.73(2)°, γ = 94.94(2)°, R₁ = 0.0577. 2 : Space group P2₁/c, Z = 2, lattice dimension at ‐70°C: a = 1003.0(1), b = 1371.8(2), c = 1974.0(1) pm, β = 93.30(1)°, R₁ = 0.0458. The dimeric anions of 1 and 2 form planar, centrosymmetric complex units.     

Zur Strukturchemie der Alkyl- und Arylhalogenoarsenate(III), [Me2As2Cl5]–, [RAsCl3]–, [R2As2Br6]2– (R = Me,Et, Ph) und [Ph2AsX2]– (X = Cl,Br)

Structural Chemistry of the Alkyl- and Arylhaloarsenates(III) [Me₂As₂Cl₅]^–, [RAsCl₃]^–, [R₂As₂Br₆]^2– (R = Me, Et, Ph) and [Ph₂AsX₂]^– (X = Cl, Br) The alkyl- and arylhaloarsenates(III) [Ph₄P][Me₂As₂Cl₅] ( 1 ), [Ph₄P][RAsCl₃] (R = Me, Et, Ph, 2 – 4 ), [Me₃PhN][PhAsCl₃] ( 5 ), [Ph₄P]₂[R₂As₂Br₆] (R = Me, Et, Ph, 6 – 8 ), [n-Pr₄N][Ph₂AsCl₂] ( 9 ) and [n-Bu₄N][Ph₂AsBr₂] ( 10 ) have been prepared and their structures established by X-ray diffraction. In contrast to the chloroarsenates(III) 2 – 5 , which all contain isolated ψ-trigonal bipyramidal anions [RAsCl₃]^–, the analogous bromoarsenates(III) 6 – 8 exhibit dimeric structures. Whereas the trans sited As–Cl distances in 2 and 3 are very similar a pronounced degree of asymmetry is apparent for the Cl–As–Cl three-centre bonds in 4 and 5 [2.396(1) and 2.602(1) Å in 5]. In 6 and 7 C_i symmetry related RAsBr₂ units are connected through long As…Br bonds [2.926(1) and 3.116(2) Å in 6 ]. The bromophenylarsenate(III) anion of 8 which contains two effectively undistorted ψ-trigonal bipyramids [PhAsBr₃]^– associated by weak As…Br interactions [3.117(2) Å]. In view of its very long bridging As…Cl distances the [Me₂As₂Cl₅]^– anion in 1 can, as 6 an 7 , be regarded as two MeAsCl₂ molecules weakly linked through a chloride ion.     

Synthese und Kristallstrukturen von [(Ph3As)2CCN–MnBr3], [(Ph3As)2CCN–CoBr3] und [(Ph3As)2CCN]+CuBr2–

Syntheses and Crystal Structures of [(Ph₃As)₂CCN–MnBr₃], [(Ph₃As)₂CCN–CoBr₃], and [(Ph₃As)₂CCN]⁺CuBr₂^– The di(arsa)acetonitrilium bromide [(Ph₃As)₂CCN]Br reacts with the anhydrous dibromides of manganese and cobalt in acetonitrile to form the molecular complexes [(Ph₃As)₂CCN–MBr₃] [M = ( 1 ), Co( 2 )] with zwitterionic structures. With copper(I)bromide, however, the ionic compound [(Ph₃As)₂CCN]⁺CuBr₂^– ( 3 ) is formed. All complexes are characterized by IR spectroscopy and by crystal structure analyses. 1 and 2 crystallize isotypically with each other in the space group P 1 with two formula units per unit cell. The MBr₃^– fragments in the molecular complexes are connected to the N atom of the [(Ph₃As)₂CCN]⁺ cation showing bond angles C–N–Mn of 156.9° and C–N–Co of 161°, and distances Mn–N of 215.6 pm and Co–N of 201 pm. In 3 , on the other hand, (space group C2/c, Z = 4) the ions [(Ph₃As)₂CCN]⁺ and the linear Br–Cu–Br^– ion are to be found concurrent but separate.     

Darstellung,Kristallstrukturen und Schwingungsspektren von trans‐[Pt(N3)4X2]2–, X = Cl,Br, I

Synthesis, Crystal Structures, and Vibrational Spectra of trans ‐[Pt(N₃)₄X₂]^2–, X = Cl, Br, I By oxidative addition to (n‐Bu₄N)₂[Pt(N₃)₄] with the elemental halogens in dichloromethane trans‐(n‐Bu₄N)₂[Pt(N₃)₄X₂], X = Cl, Br, I are formed. X‐ray structure determinations on single crystals of trans‐(Ph₄P)₂[Pt(N₃)₄Cl₂] (triclinic, space group P1, a = 10.352(1), b = 10.438(2), c = 11.890(2) Å, α = 91.808(12), β = 100.676(12), γ = 113.980(10)°, Z = 1), trans‐(Ph₄P)₂[Pt(N₃)₄Br₂] (triclinic, space group P1, a = 10.336(1), b = 10.536(1), c = 12.119(2) Å, α = 91.762(12), β = 101.135(12), γ = 112.867(10)°, Z = 1) and trans‐(Ph₄P)₂[Pt(N₃)₄I₂] (triclinic, space group P1, a = 10.186(2), b = 10.506(2), c = 12.219(2) Å, α = 91.847(16), β = 101.385(14), γ = 111.965(18)°, Z = 1) reveal, that the compounds crystallize isotypically with octahedral centrosymmetric complex anions. The bond lengths are Pt–Cl = 2.324, Pt–Br = 2.472, Pt–I = 2.619 and Pt–N = 2.052–2.122 Å. The approximate linear Azidoligands with N^α–N^β–N^γ‐angles = 172.1–176.8° are bonded with Pt–N^α–N^β‐angles = 116.2–121.9°. In the vibrational spectra the platinum halogen stretching vibrations of trans‐(n‐Bu₄N)₂[Pt(N₃)₄X₂] are observed in the range of 327–337 (X = Cl), at 202 (Br) and in the range of 145–165 cm^–1 (I), respectively. The platinum azide stretching modes of the three complex salts are in the range of 401–421 cm^–1. Based on the molecular parameters of the X‐ray determinations the IR and Raman spectra are assigned by normal coordinate analysis. The valence force constants are f_d(PtCl) = 1.90, f_d(PtBr) = 1.64, f_d(PtI) = 1.22, f_d(PtN^α) = 2.20–2.27 and f_d(N^αN^β, N^βN^γ) = 12.44 mdyn/Å.     

Synthese und Kristallstrukturen von (PPh4)2[As2Se4Cl12] und (PPh4)2[As2Se4Br12]

Synthesis and Crystal Structures of (PPh₄)₂[As₂Se₄Cl₁₂] and (PPh₄)₂[As₂Se₄Br₁₂] The reaction of PPh₄Cl and As₂Se₃ with SOCl₂ or with chlorine in dichloromethane affords (PPh₄)₂[As₂Se₄Cl₁₂] with good yields. From PPh₄Br, As₂Se₃ and bromine the corresponding bromo compound was obtained. According to the X-ray crystal structure determinations both compounds are isotypic, crystallizing in the space group of P1 . In the anions two Se₂X₂ molecules are linked with two X^? ions forming an Se₄X₂ ring in chair conformation. Each X^?-ion is associated with an additional AsX₃ molecule (X = Cl, Br).     

Neue Synthesen von Me2SbX (X = Cl,I) und Kristallstrukturen von Me2SbI und [(Me3Si)2CH]2SbCl

Novel Syntheses of Me₂SbX (X = Cl, I) and Crystal Structures of Me₂SbI and [(Me₃Si)₂CH]₂SbCl The crystal structures of Me₂SbI (Me = CH₃) and [(Me₃Si)₂CH]₂SbCl have been determined by X‐ray methods. Both molecules are pyramidal. The Me₂SbI molecules are associated to chains through short intermolecular Sb…I distances (366,7(1) pm) with linear I–Sb…I units (171,87(4)°) and bent Sb–I…Sb bridges (116,83(3)°).     

Darstellung,Kristallstrukturen und Schwingungsspektren von [(Mo6X)Y]2–; Xi = Cl,Br; Ya = NO3, NO2

Synthesis, Crystal Structures, and Vibrational Spectra of [(Mo₆X)Y]^2–; Xⁱ = Cl, Br; Y^a = NO₃, NO₂ By treatment of [(Mo₆X)Y]^2–; Xⁱ = Y^a = Cl, Br with AgNO₃ or AgNO₂ by strictly exclusion of oxygene in acetone the hexanitrato and hexanitrito cluster anions [(Mo₆X)Y]^2–, Y^a = NO₂, NO₃ are formed. X-ray structure determinations of (Ph₄As)₂[(Mo₆Cl)(NO₃)] · 2 Me₂CO ( 1 ) (monoclinic, space group P2₁/n, a = 12.696(3), b = 21.526(1), c = 14.275(5) Å, β = 115.02(2)°, Z = 2), (n-Bu₄N)₂[(Mo₆Br)(NO₃)] · 2 CH₂Cl₂ ( 2 ) (monoclinic, space group P2₁/n, a = 14.390(5), b = 11.216(5), c = 21.179(5)Å, β = 96.475(5)°, Z = 2) and (Ph₄P)₂[(Mo₆Cl)(NO₂)] (3) (monoclinic, space group P2₁/n, a = 11.823(5), b = 13.415(5), c = 19.286(5) Å, β = 105.090(5)°, Z = 2) reveal the coordination of the ligands via O atoms with (Mo–O) bond lengths of 2.11–2.13 Å, and (MoON) angles of 122–131°. The vibrational spectra of the nitrato compounds show the typical innerligand vibrations ν_as(NO₂) (∼ 1500), ν_s(NO₂) (∼ 1270) and ν(NO) (∼ 980 cm^–1). The stretching vibrations ν(N=O) at 1460–1490 cm^–1 and ν(N–O) in the range of 950–1000 cm^–1 are characteristic for nitrito ligands coordinated via O atoms.     

Neue mehrkernige Indium–Stickstoff‐Verbindungen – Synthese und Kristallstrukturen von [In4X4(NtBu)4] (X = Cl,Br, I) und [In3Br4(NtBu)(NHtBu)3]

New Polynuclear Indium Nitrogen Compounds – Synthesis and Crystal Structures of [In₄X₄(N^tBu)₄] (X = Cl, Br, I) and [In₃Br₄(N^tBu)(NH^tBu)₃] The reaction of the indium trihalides InX₃ (X = Cl, Br, I) with LiNH^tBu in THF leads to the In₄N₄‐heterocubanes [In₄X₄(N^tBu)₄] (X = Cl 1 , Br 2 , I 3 ). Additionally [In₃Br₄(N^tBu)(NH^tBu)₃] ( 4 ) was obtained as a by‐product in the synthesis of 2 . 1 – 4 have been characterized by x‐ray crystal structure analysis. 1 – 3 consist of In₄N₄ heterocubane cores with an alternating arrangement of In and N atoms. The In atoms are coordinated nearly tetrahedrally by three N‐atoms and a terminal halogen atom. 4 contains a tricyclic In₃N₄ core which can be formally derived from an In₄N₄‐heterocubane by removing one In atom.     

Kristallstrukturen der Samarium-Amido-Komplexe [Sm(l-X){N(SiMe3)2}2(THF)]2 mit X = Cl,Br

Crystal Structures of the Samarium Amido Complexes [Sm(l-X){N(SiMe₃)₂}₂(THF)]₂ with X = Cl, Br The crystal structures of the title compounds have been determined by X-ray methods. [Sm(μ-Cl) · {N(SiMe₃)₂}₂(THF)]₂ ( 1 ): Space group P2₁/n, Z = 2, lattice dimensions at 223 K: a = 1429.5(2), b = 1302.3(3), c = 1658.6(3) pm, β = 114.212(10)°, R = 0.0561. [Sm(μ-Br) · {N(SiMe₃)₂}₂(THF)]₂ ( 2 ): Space group Pbca, Z = 4, lattice dimensions at 223 K: a = 1850.0(7), b = 1611.0(9), c = 1888.1(6) pm, R = 0.0497. 1 and 2 form centrosymmetric dimeric complexes via μ-X-halogeno bridges. The samarium atoms are coordinated in a distorted trigonal-bipyramidal surrounding, the THF molecule and one of the bridging halogen atoms being in axial positions.     

Darstellung,Schwingungsspektren und Kristallstrukturen von [(Ph3P)2N]2[(W6Cl)I] · 2 Et2O · 2 CH2Cl2 und [(Ph3P)2N]2[(W6Cl)(NCS)] · 2 CH2Cl2

Synthesis, Crystal Structures, and Vibrational Spectra of [(Ph₃P)₂N]₂[(W₆Cl )I ] · 2 Et₂O · 2 CH₂Cl₂ and [(Ph₃P)₂N]₂[(W₆Cl )(NCS) ] · 2 CH₂Cl₂ By treatment of [(W₆Cl)I]^2– with (SCN)₂ in dichloromethane at –20 °C the hexaisothiocyanato cluster anion [(W₆Cl)(NCS)]^2– is formed. X‐ray structure determinations have been performed on single crystals of [(Ph₃P)₂N]₂[(W₆Cl)I] · 2 CH₂Cl₂ · 2 Et₂O ( 1 ) (triclinic, space group P1, a = 10.324(5), b = 14.908(3), c = 17.734(8) Å, α = 112.78(2)°, β = 99.13(3)°, γ = 92.02(3)°, Z = 1) and [(Ph₃P)₂N]₂[(W₆Cl)(NCS)] · 2 CH₂Cl₂ ( 2 ) (triclinic, space group P1, a = 11.115(2), b = 14.839(2), c = 17.036(3) Å, α = 104.46(1)°, β = 105.75(2)°, γ = 110.59(1)°, Z = 1). The thiocyanate ligands of 2 are bound exclusively via N atoms with W–N bond lengths of 2.091–2.107 Å, W–N–C angles of 173.1–176.9° and N–C–S angles of 178.1–179.3°. The vibrational spectra exhibit characteristic innerligand vibrations at 2067–2045 (ν_CN), 879–867 (ν_CS) and 490–482 (δ_NCS). Based on the molekular parameters of the X‐ray determination of 1 the vibrational spectra of the corresponding (n‐Bu₄N) salt of 1 are assigned by normal coordinate analysis. The valence force constants are f_d(WW) = 1.61, f_d(WI) = 1.23 and f_d(WCl) = 1.10 mdyn/Å.     

Über Chalkogenidhalogenide des Rheniums: Synthese und Kristallstrukturen der Dreieckscluster Re3E7X7 (E = S,Se; X = Cl,Br)

On Chalcogenide Halogenides of Rhenium: Synthesis and Crystal Structures of the Triangular Clusters Re₃E₇X₇ (E = S, Se; X = Cl, Br) The compounds Re₃E₇X₇ are obtained from rhenium tetrahalides ReX₄, elemental chalcogens and the respective chalcogen halides E₂X₂ or SeX₄ (E = S, Se; X = Cl, Br). Re₃S₇Cl₇, Re₃S₇Br₇ and Re₃Se₇Br₇ are formed in solutions of sulfur or selenium halides or SiBr₄ in form of black crystals and crystallize isotypically in the trigonal space group P31c. Re₃Se₇Cl₇ is formed by solid state reaction of ReCl₄, Se and SeCl₄ or by thermal decomposition of Se₄[ReCl₆], crystallizing as red, in thin layers transparent crystals in the orthorhombic space group Pbcm. The crystal structures consist of discrete positively charged cluster units and halide ions according to the formula [Re₃(μ₃-E)(μ₂-E₂)₃X₆]⁺X^–. In the rhenium triangular clusters the Re–Re distances range from 269,0 to 270,4 pm for the sulfur and from 273,3 to 275,3 pm for the selenium containing compounds. The Re₃ units are capped by chalcogen atoms, three E₂ groups form bridges over the edges of the Re₃ triangles. The trigonal and the orthorhombic structure type show differences in the site symmetry of the clusters (C₃ vs. C_s) and in the stacking sequence of the molecules, which are packed in the motif of a closest packing of spheres.     

Die Kristallstrukturen der Dicaesium-Dodekahalogeno-closo-Dodekaborate Cs2[B12X12] (X = Cl,Br, I) und ihrer Hydrate

The Crystal Structures of the Dicesium Dodecahalogeno-closo-Dodecaborates Cs₂[B₁₂X₁₂] (X = Cl, Br, I) and their Hydrates The perhalogenated derivatives Cs₂[B₁₂X₁₂] (X = Cl - I) have been synthesized by reaction of Cs₂[B₁₂H₁₂] with the respective elemental halogens (Cl₂, Br₂ and I₂). Upon recrystallization from aqueous solution colourless, face-rich single crystals of the dihydrates (Cs₂[B₁₂X₁₂] · 2 H₂O) are obtained first which can be dehydrated topotactically via the monohydrates (Cs₂[B₁₂X₁₂] · H₂O) leaving to the solvent-free compounds (Cs₂[B₁₂X₁₂]) behind without loss of their crystallinity. The ionic cesium salts were characterized by single crystal X-ray diffraction. All three halogenoborates are isostructural and they crystallize at room temperature in the trigonal space group (Cs₂[B₁₂Cl₁₂]: a = 959.67(3) pm, c = 4564.2(2) pm; Cs₂[B₁₂Br₁₂]: a = 997.92(3) pm, c = 4766.4(3) pm; Cs₂[B₁₂I₁₂]: a = 1047.05(4) pm, c = 5018.3(3) pm; Z = 6). The crystal structures consist of a cubic closest packed host lattice formed by two crystallographically inequivalent quasi-icosahedral [B₁₂X₁₂]^2- anions (Cs₂[B₁₂Cl₁₂]: d(B-B) = 178 - 179 pm, d(B-Cl) = 179 - 180 pm; Cs₂[B₁₂Br₁₂]: d(B-B) = 176 - 180 pm, d(B-Br) = 195 - 197 pm; Cs₂[B₁₂I₁₂]: d(B-B) = 177 - 182 pm, d(B-I) = 214 - 217 pm). By ordered occupation of half of the tetrahedral and formally all octahedral interstices in every intermediate layer with Cs⁺ cations, a structure emerges where (Cs1)⁺ is trigonally non-planar coordinated by three (CN = 9) and (Cs2)⁺ tetrahedrally coordinated by four (CN = 12) [B₁₂X₁₂]^2- anions. Thereby triangular faces of halogen atoms of the icosahedral clusters are coordinatively effective in both cases. In their mono- and dihydrates the incomplete coordination sphere of (Cs1)⁺ is completed by one and two water molecules, respectively. The thermal decomposition of the dicesium dodecahalogeno-closo-dodecaborate hydrates and their dehydration products was investigated using DTA/TG methods in a temperature range between room temperature and 1200 °C. Additionally the compounds were also characterized by ¹¹B-NMR spectroscopy in aqueous solution.     

Compounds with Cluster Cations together with Cluster Anions [(M6X12)(EtOH)6]2+ besides [(Mo6Cl8)Cl4X2]2– (M = Nb,Ta; X = Cl,Br) – Synthesis and Crystal Structures

Compounds consisting of both cluster cations and cluster anions of the composition [(M₆X₁₂)(EtOH)₆][(Mo₆Cl₈)Cl₄X₂] · n EtOH · m Et₂O (M = Nb, Ta; X = Cl, Br) have been prepared by the reaction of (M₆X₁₂)X₂ · 6 EtOH with (Mo₆Cl₈)Cl₄. IR data are given for three compounds. The structures of [(Nb₆Cl₁₂)(EtOH)₆][(Mo₆Cl₈)Cl₆] · 3 EtOH · 3 Et₂O 1 and [(Ta₆Cl₁₂)(EtOH)₆][(Mo₆Cl₈)Cl₆] · 6 EtOH 2 have been solved in the triclinic space group P1 (No. 2). Crystal data: 1 , a = 10.641(2) Å, b = 13.947(2) Å, c = 15.460(3) Å, α = 65.71(2)°, β = 73.61(2)°, γ = 85.11(2)°, V = 2005.1(8) ų and Z = 1; 2 , a = 11.218(2) Å, b = 12.723(3) Å, c = 14.134(3) Å, α = 108.06(2)°, β = 101.13(2)°, γ = 91.18(2)°, V = 1874.8(7) ų and Z = 1. Both structures are built of octahedral [(M₆Cl₁₂)(EtOH)₆]²⁺ cluster cations and [(Mo₆Cl₈)Cl₆]^2– cluster anions, forming distorted CsCl structure types. The Nb–Nb and Ta–Ta bond lengths of 2.904 Å and 2.872 Å (mean values), respectively, are rather short, indicating weak M–O bonds. All O atoms of coordinated EtOH molecules are involved in H bridges. The Mo–Mo distances of 2.603 Å and 2.609 Å (on average) are characteristic for the [(Mo₆Cl₈)Cl₆]^2– anion, but there is a clear correlation between the number of hydrogen bridges to the terminal Cl and the corresponding Mo–Cl distances.     

Synthese und Struktur von [(Me2PhP)3Cl2ReN]2ReCl4, [(Me2PhP)3Cl2ReN]2ReCl4 · 2 SbCl3 und [Re(NH)Cl2(PMe2Ph)3][SbCl6]

Synthesis and Structure of [(Me₂PhP)₃Cl₂ReN]₂ReCl₄, [(Me₂PhP)₃Cl₂ReN]₂ReCl₄ · 2 SbCl₃ and [Re(NH)Cl₂(PMe₂Ph)₃][SbCl₆] The reaction of ReNCl₂(PMePh)₃ with SbCl₅ in toluene yields the trinuclear complex [(Me₂PhP)₃Cl₂Re≡N]₂ReCl₄ · 2 SbCl₃ ( 1 · 2 SbCl₃). It forms triclinic crystals with the composition 1 · 2 SbCl₃, as well as monoclinic crystals 1 · 2 SbCl₃ · 4 C₇H₈. The monoclinic crystals with the space group P2₁/c, and a = 1212.3(2), b = 2098.5(4), c = 1827.7(3) pm, β = 95.51(1)°, Z = 2, have been used for a crystal structure determination. In the centrosymmetric complex 1 two complexes ReNCl₂(PMe₂Ph)₃ coordinate with their nitrido ligands a square planar, central unit ReCl₄. The SbCl₃ molecules are coordinated by chlorine bridges to Cl atoms of 1 , and, in addition, connect the complexes 1 with each other. The SbCl₃ free compound 1 is obtained in good yield by the reaction of ReNCl₂(PMePh)₃ with ReCl₄(NCEt)₂. It crystallizes in the triclinic space group P1 with a = 1037.7(3), b = 1153.0(2), c = 1393.8(3) pm, α = 72.31(2)°, β = 74.06(2)°, γ = 67.94(2)°, and Z = 1. The bond lengths of the Re–N triple bonds are 172 pm in 1 and 170 pm in 1 · 2 SbCl₃. By the reaction of ReNCl₂(PMePh)₃ with SbCl₅ in CH₂Cl₂ the solvent is decomposed forming HCl which protonates the nitrido ligand to afford the imido complex [Re(NH)Cl₂(PMe₂Ph)₃][SbCl₆] ( 2 ) crystallizing in the monoclinic space group P2₁/n with a = 1221.4(2), b = 1358.6(2), c = 2177.3(1) pm, β = 92,72(1)° and Z = 4. The Re–N distance in the almost linear unit Re≡N–H is 169,1 pm.     

Synthese,Struktur und Eigenschaften von [nacnac]MX3‐Verbindungen (M = Ge,Sn; X = Cl,Br, I)

Synthesis, Structure, and Properties of [nacnac]MX₃ Compounds (M = Ge, Sn; X = Cl, Br, I) Reactions of [nacnac]Li [(2,6‐ⁱPr₂C₆H₃)NC(Me)C(H)C(Me)N(2,6‐ⁱPr₂C₆H₃)]Li ( 1 ) with SnX₄ (X = Cl, Br, I) and GeCl₄ in Et₂O resulted in metallacyclic compounds with different structural moieties. In the [nacnac]SnX₃ compounds (X = Cl 2 , Br 3 , I 4 ) the tin atom is five coordinated and part of a six‐membered ring. The Sn–N‐bond length of 3 is 2.163(4) Å and 2.176(5) Å of 4 . The five coordinated germanium of the [nacnac]GeCl₃ compound 5 shows in addition to the three chlorine atoms further bonds to a carbon and to a nitrogen atom. In contrast to the known compounds with the [nacnac] ligand the afore mentioned reaction creates a carbon–metal‐bond (1.971(3) Å) forming a four‐membered ring. The Ge–N bond length (2.419(2) Å) indicates the formation of a weakly coordinating bond.     

Einfache Synthese von Alkylaluminium‐ und Alkylgalliumhydriden – Kristallstrukturen von [(Me3C)2GaH]3 und den neuartigen Sesquihydriden [(Me3C)2EH]2[EH2CMe3]2 (E = Al,Ga)

Facile Syntheses of Alkylaluminium and Alkylgallium Hydrides – Crystal Structures of [(Me₃C)₂GaH]₃ and the Novel Sesquihydrides [(Me₃C)₂EH]₂[EH₂CMe₃]₂ (E = Al, Ga) The facile syntheses of some important, sterically highly shielded dialkylaluminium hydrides R₂AlH [R = CMe₃, CH(SiMe₃)₂] succeeded by the reaction of the corresponding trialkylaluminium compounds with the alane adduct AlH₃ × NMe₂Et in a 2 to 1 molar ratio. This route is not suitable for the synthesis of monoalkylaluminium dihydrides. An excess of AlH₃ yielded the novel sesquihydride [(Me₃C)₂AlH]₂[AlH₂CMe₃]₂ ( 3 ) as the hydride richest compound which possesses an unprecedented heterocycle comprising four aluminium and four hydrogen atoms in the solid state. The dialkylgallium hydride (Me₃C)₂GaH ( 4 ) was formed on a similar route by the treatment of tri(tert‐butyl)gallane with the adduct GaH₃ · NMe₂Et. As shown by a crystal structure determination, compound 4 is a trimer in the solid state possessing a Ga₃H₃ heterocycle. A gallium sesquihydride analogous to compound 3 , [(Me₃C)₂GaH]₂[GaH₂CMe₃]₂ ( 5 ), was formed on employing an excess of GaH₃.     

Darstellung von trans-[Mo6Cl8]Cl4Br22−ausgehend von kristallisierten [Mo6Cl8]Cl4(H2O)2 und die Kristallstruktur von [(C6H5)4As]2[Mo6Cl8]Cl4Br2

Preparation of trans-[Mo₆Cl₈]Cl₄Br₂^2? Starting from Crystalline [Mo₆Cl₈]Cl₄(H₂O)₂ and Crystal Structure of [(C₆H₅)₄As]₂[Mo₆Cl₈]Cl₄Br₂ The synthesis of the title compound is successful if the crystallized [(Mo₆Cl₈)Cl₄(H₂O)₂] containing the H₂O molecules in trans-position reacts with HBr + [(C₆H₅)₄As]Br in ethanol in a heterogeneous reaction. The X-ray structure investigation confirms the existence of discrete trans-Br-substituted cluster anions of composition [(Mo₆Cl₈)Cl₄Br₂]^2? in the crystal. The reaction in homogeneous solutions proceeds to Br-enriched compounds. [(C₆H₅)₄As]₂[(Mo₆Cl₈)Cl₄Br₂] crystallizes in the triclinic space group P¯1 with a = 11.071(2), b = 11.418(2), c = 12.813(2) Å, α = 116.10(2), β = 95.27(2) and γ = 94.41(2)° (?133°C). The crystal structure at ?133°C was determined from single crystal X-ray diffraction data (R₁ = 0.026). The [(Mo₆Cl₈)Cl₄Br₂]^2?-anions are not completely ordered but distributed statistically among the three positions which are possible within the limits of the ordered [Mo₆Cl₈]-cores (ratio 11:5:4). The frameworks of the anions consist of Mo₆ cluster units with (slightly distorted) octahedral arrangement of the metal atoms (d(Mo? Mo): 2.600(1) up to 2.614(1) Å), which are coordinated by the halogeno ligands in a square-pyramidal manner. The details of the structure will be discussed and compared with similar [(Mo₆X₈)Y₄] cluster units (X, Y ? Cl, Br).     

Organometallated Halonium Salts of the Type [{Cp(CO)2Fe}2X]SbY6 (X = Cl,Br, I; Y = F,Cl)

The reaction of CpFe(CO)₂X (X = Cl, Br, I) with SbY₅ (Y = F, Cl) in toluene leads to the cationic, halogen‐bridged compounds [{Cp(CO)₂Fe}₂X]SbY₆ ( 1 – 6 ). The halide of CpFe(CO)₂X is eliminated by the Lewis acid SbY₅, and the fragment “CpFe(CO)₂⁺” reacts with further CpFe(CO)₂X to form the halogen bridge between both the organometallic substituents. The exclusive formation of the counter anion SbY₆^– is caused by the oxidizing action of the antimony pentahalides, by which SbY₃ and the interhalogens XY are always obtained. The compounds have been characterized by their NMR‐, IR‐ and Mass spectra, the compounds 1 – 3 and 6 additionally by single crystal structure analyses. They show decreasing bond angles Fe–X–Fe following the range Cl → Br → I and the VSEPR concept; the two CpFe(CO)₂ groups are staggered with the dihedral angle Cp(centre)–Fe–Fe–Cp(centre) of about 160°.     

Azidoberyllate mit Adamantanstruktur: Synthese,IR‐Spektren und Kristallstrukturen von (Ph4P)2[Be4X4(μ‐N3)6] (X = Cl,Br)

Azido Beryllates with Adamantan‐like Structures: Synthesis, IR Spectra, and Crystal Structures of (Ph₄P)₂[Be₄X₄(μ‐N₃)₆] (X = Cl, Br) The azido beryllates (Ph₄P)₂[Be₄X₄(μ‐N₃)₆] (X = Cl 1a , X = Br 1b ) have been prepared by the reaction of Me₃SiN₃ with the halogeno beryllates (Ph₄P)₂[Be₂Cl₆] and (Ph₄P)₂[Be₂Br₆], respectively, in CH₂Cl₂ and CH₂Br₂ solution, respectively. Both complexes form moisture sensitive, colourless crystals, which are nonexplosive with respect to mechanical or thermal stress. They are characterized by IR spectroscopy and by crystal structure determinations. 1a and 1b crystallize isotypically in the space group C2/c with 12 formula units per unit cell. Whereas 1a was only refined to R₁ = 0.13, which is caused by disordering, 1b could be refined to R₁ = 0.066. The structures contain adamantanlike dianions [Be₄X₄(μ‐N₃)₆]^2— with two symmetry nonequivalent individuals which differ only slightly from one another. The Be₄N₆ core is formed by bridging function of the α‐nitrogen atoms of the azide groups with BeN bond lengths of 172.5 and bond lengths N_α—N_β = 123.2 pm and N_β—N_γ = 113.1 pm on average in the structure of 1b .     

Neue viergliedrige GaE‐ und InE‐Ringverbindungen: Synthese und Kristallstruktur von [Et2InE(SiMe3)2]2 und [GaCl(PtBu2Me)E(SiMe3)]2 (E = P,As)

New GaE and InE Four Membered Ring Compounds: Syntheses and Crystal Structures of [Et₂InE(SiMe₃)₂]₂ and [GaCl(P t Bu₂Me)E(SiMe₃)]₂ (E = P, As) Et₃In · PR₃ (R = Et, iPr) reacts with H₂ESiMe₃ under liberation of C₂H₆ and EH₃ to form the cyclic compounds [Et₂InE(SiMe₃)₂]₂ ( 1 a : E = P, 1 b : E = As). 1 consists of a planar four membered In₂E₂ ring in which the indium and phosphorus or arsenic atoms are four coordinated. In contrast, the phosphorus/arsenic atoms in [GaCl(PtBu₂Me)E(SiMe₃)]₂ ( 2 a : E = P, 2 b : E = As) only have the coordination number three. 2 results from the reaction of GaCl₃ · PtBu₂Me with As(SiMe₃)₃ or Li₂PSiMe₃ respectively, and displays a folded four membered Ga₂E₂ ring as central structural motif. 1 and 2 have been characterised by single crystal X‐ray diffraction analysis as well as ¹H and ³¹P{¹H} NMR spectroscopy.