Bis(1,2-dimethoxyethan-O,O′)lithium-phosphanid, -arsanid und -chlorid – drei neue Vertreter des Bis(1,2-dimethoxyethan-O,O′)lithium-bromid-Typs

Metal Derivatives of Molecular Compounds. IX. Bis(1,2-dimethoxyethane- O,O′ )lithium Phosphanide, Arsanide, and Chloride – Three New Representatives of the Bis(1,2-dimethoxyethane- O,O′ )lithium Bromide Type Experiments to obtain thermally unstable lithium silylphosphanide at –60 °C from a 1,2-dimethoxyethane solution resulted in the isolation of its dismutation product bis(1,2-dimethoxyethane-O,O′)lithium phosphanide ( 1 ). The homologous arsanide 2 precipitated after a frozen solution of arsane in the same solvent had been treated with lithium n-butanide at –78 °C. Unexpectedly, too, the analogous chloride 3 and bromide 4 were formed in reactions of 1-chloro-2,2-bis(trimethylsilyl)-1λ³-phosphaethene with (1,2-dimethoxyethane-O,O′)lithium bis(trimethylsilyl)stibanide and of lithium 1,2,3,4,5-pentaphenyl-2,3-dihydro-1λ³-phosphol-3-ide with ω-bromostyrene, respectively. The monomeric complexes 1 {–100 ± 3 °C; a = 1391.1(4); b = 809.8(2); c = 1249.1(3) pm; β = 102.84(2)°}, 2 {–100 ± 3 °C; a = 1398.3(4); b = 819.8(3); c = 1258.5(4) pm; β = 103.35(2)°} and 3 {–100 ± 3 °C; a = 1308.4(2); b = 788.2(1); c = 1195.6(1) pm; β = 95.35(1)°} crystallize in the monoclinic space group C2/c with four solvated ion pairs in the unit cell; they are isotypic with bis(1,2-dimethoxyethane-O,O′)lithium bromide ( 4 ) {–73 ± 2 °C; a = 1319.0(2); b = 794.1(1); c = 1214.3(2) pm; β = 96.22(1)°}, already studied by Rogers et al. [13] at room temperature. The neutral complexes show a trigonal bipyramidal configuration of symmetry C₂, pnicogenanide or halide anions occupying equatorial sites {Li–P 260.4(4); Li–As 269.8(6); Li–Cl 238.6(7); Li–Br 256.3(10) pm} and the chelate ligands spanning equatorial and axial positions {Li–O_eq 205.4(4) to 207.4(4); Li–O_ax 208.9(3) to 215.5(2) pm}. The coordination within the (dme)₂Li fragment, the Li–X distances (X = P, As, Cl, Br), the structure of the chelate rings, and the packing of the neutral complexes are discussed in detail.     

Common Features in the Crystal Structures of the Compounds Bis(dimethylstibanyl)oxane and ‐sulfane,and the Minerals Valentinite and Stibnite (Grauspießglanz)

Bis(dimethylstibanyl)oxane ( 1 ) and ‐sulfane ( 2 ), the two simplest organoelement species with an Sb–E–Sb fragment (E = O, S), were prepared by alkaline hydrolysis of bromodimethylstibane and by oxidation of tetramethyldistibane with sulfur [18], respectively. As shown by an x‐ray structure analysis of compound 1 (m. p. < –20 °C; P2₁2₁2₁, a = 675.9(2), b = 803.1(2), c = 1666.8(4) pm at –70 ± 2 °C; Z = 4; R1 = 0.042), the molecules (O–Sb 198.8 and 209.9 pm, Sb–O–Sb 123.0°) adopt a syn‐anti conformation in the solid state and are arranged in zigzag chains along [010] via weak intermolecular O‥Sb interactions (258.5 pm, Sb–O‥Sb 117.8°, O‥Sb–O 173.5°) making use, however, of only one Me₂Sb moiety. Primary and secondary bond lengths and angles agree very well with corresponding values published for valentinite, the orthorhombic modification of antimony(III) oxide [3]. Bis(dimethylstibanyl)sulfane ( 2 ) (m. p. 29 to 31 °C) crystallizes in the uncommon space group P6₅22 (a = 927.8(3), c = 1940.9(7) pm at –100 ± 2 °C; Z = 6; R1 = 0.021). Owing to coordination numbers of (1 + 1) and (2 + 2) for both Me₂Sb groups and the sulfur atom, respectively, molecules with an approximate syn‐syn conformation (S–Sb 249.8 pm, Sb–S–Sb 92.35°) build up a three‐dimensional net of double helices which are linked together by Sb‥S contacts (316.4 pm). These parameters shed more light onto the rather complicated structure and bonding situation in stibnite (antimony(III) sulfide [4]). The molecular packing of compound 2 is compared with the structures of relevant inorganic solids, especially with that of β‐quartz [37].     

Synthese und Einkristallröntgenstrukturanalyse von Bromdi(isopropenyl)bismutan

Synthesis and Single Crystal X‐Ray Structure Analysis of Bromodi(isopropenyl)bismuthane Tri(isopropenyl)bismuthane ( 1 ) reacts with bromine to form bromodi(isopropenyl)bismuthane ( 2 ) and dibromo(isopropenyl)bismuthane ( 3 ). The single crystal X‐ray structure determination of 2 (monoclinic, P 2₁/c; a = 1058.6(3), b = 1127.0(3), c = 1561.3(4) pm, and β = 109.26(2)°; Z = 8 molecules; d_c = 2.803 g/cm³; R = 0.059) shows two crystallographically independent molecules which are connected by Bi–Br…Bi bridges (Bi–Br 282.3(2) and 284.7(2); Br…Bi 302.9(2) and 303.6(2) pm) forming helical chains directed along the b‐axis of the unit cell. Every turn of the helix (360°) consists of four molecules and corresponds to the length of the b‐axis (1127.0(3) pm).     

Hydrothermalsynthese und Kristallstruktur der Münzmetall‐Quecksilber‐Chalkogenidhalogenide CuHgSeBr,AgHgSBr und AgHgSI

Hydrothermal Synthesis and Crystal Structure of the Coinage Metal Mercury Chalcogenide Halides CuHgSeBr, AgHgSBr, and AgHgSI The hydrothermal reaction of CuBr and HgSe in concentrated aqueous HBr as solvent at 285 °C yields red crystals of CuHgSeBr, the hydrothermal reaction of AgX (X = Br, I) and HgS in half‐concentrated aqueous HX (X = Br, I) as solvent at 300/400 °C yields yellow crystals of AgHgSBr and AgHgSI. The compounds crystallize isotypically (orthorhombic, Pmma, a = 1020.1(3) pm, b = 431.2(1) pm, c = 925.6(3) pm for CuHgSeBr, a = 964.8(8) pm, b = 466.1(4) pm, c = 942.6(6) pm for AgHgSBr und a = 1015.9(2) pm, b = 464.77(5) pm, c = 984.9(2) pm for AgHgSI, Z = 4). The structures consist of plane folded Hg–Y chains connected by pairs of distorted Y₂X₂ terahedra sharing the X–X‐edge (M = Cu, Ag; X = Br, I; Y = S, Se). Atoms of the monovalent metals M have a strongly distorted tetrahedral coordination of two halogen and two chalcogen atoms. The new structure type shows distinct differences in the arrangement of the Hg–Y chains in comparision to the already known CuHgSeCl, but represents the superposition structure of the order‐disorder phase γ‐Hg₃S₂Cl₂.     

Element-Element-Bindungen. VI. Kristallines 2-Chlor-1,3,2-benzoxathiastibol – ein mehrfach verknüpftes Koordinationspolymeres

Element-Element-Bonds. VI. Crystalline 2-Chloro-1,3,2-benzoxathiastibole – a Multiply Linked Coordination Polymer Yellow 2-chloro-1,3,2-benzoxathiastibole 4a first prepared by Anchisi and coworkers [3] from o-hydroxythiophenol and antimony trichloride, crystallizes in the monoclinic space group P2₁/n {a = 1109.9(3); b = 610.5(2); c = 1201.5(2) pm; β = 100.35(2)° at ?120 ± 3°C; Z = 4}. An X-ray structure determination (R = 0.029) shows the molecules to form coordination polymeric layers via Sb…?Cl, Sb…?O and Sb…?η²-arene interactions in the solid. Characteristic structural features are Sb? Cl…?Sb? Cl helices (Sb? Cl…?Sb 119°; Cl? Sb…?Cl 95°) and centrosymmetric, four membered Sb₂O₂-rings (O? Sb…?O 64°; Sb? O…?Sb 116°). The ligands set up a strongly distorted octahedron around the antimony atom: Sb? S 242; Sb? Cl 243; Sb…?Cl 328; Sb? O 201; Sb…?O 287; Sb…?C 338 and 341 pm; S? Sb? O 85°; S? Sb? Cl 94°; O? Sb? Cl 92°.     

Acyl- und Alkylidenphosphane. XXXII [1, 2]. Di-cyclo-hexoyl- und Diadamant-1-oylphosphan — Keto-Enol-Tautomerie und Struktur

Acyl- and Alkylidenephosphines. XXXII. Di-cyclohexoyl- and Diadamant-1-oylphosphine – Keto-Enol Tautomerism and Structure Lithium dihydrogenphosphide · DME (¹) [12] and cyclo-hexoyl or adamant-1-oyl chloride react in a molar ratio of 3:2 to give lithium di-cyclo-hexoylphosphide · DME and the corresponding diadamant-1-oylphosphide.2THF (¹) resp. Treatment of these two compounds with 85% tetrafluoroboric acid. diethylether adduct yields di-cyclo-hexoyl- ( 1b ) and diadamant-1-oylphosphine ( 1c ). In nmr spectroscopic studies 1b over a range of 203 to 343 K, a strong temperature dependence of the keto-enol equilibrium is found; thermodynamic data characteristic for the formation of the enol tautomer (ΔH⁰ = ?4.3 kJ. mol^?1; ΔS⁰ = ?9.2 J. mol^?1. K (^?1) are compared of 1,3-diketones. The enol tautomer of diadamant-1-oylphosphine ( E-1c ) as obtained from a benzene solution in thin colourless plates, crystallizes in the monoclinic space group P2₁/c {a = 722.2(2); b = 1085.5(4); c = 2434.8(5) pm; ß = 96.43(2)° at –100 ± 3°C; Z = 4}. An X- ray structure analysis (R_w = 0.033) shows bond lengths and angles to be almost identical within the enolic system (P? C 179/180; C? O 130/129; C? C(adamant-1-yl) 152/153 pm; C? P? C 99°; P? C? O 124°/124°; P? C? C 120°/120°; C? C? O 116°/116°. The geometry of the very strong, but probably asymmetric O‥H‥O bridge is discussed (O? H 120/130, O‥O 245 pm).     

Darstellung von Organylquecksilber(II)‐di(methansulfonyl)amiden und Kristallstruktur von Ph–Hg–N(SO2Me)2

Polysulfonylamines. CXXIV. Preparation of Organylmercury(II) Di(methanesulfonyl)amides and Crystal Structure of Ph–Hg–N(SO₂Me)₂ Four N,N‐disulfonylated organylmercury(II) amides R–Hg–N(SO₂Me)₂, where R is Me, ⁱPr, Me₃SiCH₂ or Ph, were obtained on treating the appropriate chlorides RHgCl with AgN(SO₂Me)₂, and characterized by ¹H and ¹³C NMR spectra. In the crystal structure of the phenyl compound (orthorhombic, space group Pbca, Z = 8, X‐ray diffraction at –95 °C), the molecule exhibits a covalent and significantly bent C–Hg–N grouping [bond angle 172.7(3)°; Hg–C 204.0(8), Hg–N 209.1(7) pm]. One sulfonyl oxygen atom forms a short intramolecular Hg…O contact [296.1(5) pm] and simultaneously catenates glide‐plane related molecules via a second Hg…O interaction 297.6(5) pm], thus conferring upon Hg^II the effective coordination number 4 and a geometrically irregular coordination polyhedron (bond angles from 173 to 54°).     

Lewis-Säure-Base-Reaktionen von Goldtrihalogeniden mit Bismuttrihalogeniden – Synthese und Kristallstrukturen von AuBiX6 (X  Cl,Br)

Lewis-Acid-Base-Reactions of Gold Trihalides with Bismuth Trihalides – Synthesis and Structures of AuBiX₆ (X ? CI, Br) Gold trihalides AuX₃ (X ? Cl, Br) react with bismuth trihalides in sealed glass ampoules to the 1 : 1 adducts AuBiX₆ (X ? Cl, Br). AuBiCl₆ is obtained by a chemical transport reaction at 220°C, whereas AuBiBr₆ was synthesized by solvothermal reaction in SiBr₄ at 150°C. Both compounds crystallize triclinic, space group P1 , Z = 4. AuBiCl₆; a = 698.3(4) pm; b = 1009.3(5) pm; c = 1381(1) pm; α = 104.98(5)°; β = 94.73(5)°; γ = 110.06(3)°; V = 867(1) · 10⁶ pm³. AuBiBr₆: a = 735.7(4) pm; b = 1055.7(5) pm; c = 1445(1) pm; α =104.88(5)°; β = 94.25(5)°; γ = 110.18(4)°; V =1001(1) ·10⁶pm³. The structures are build formally of square-planar [AuX₄]^? and chains of edge-connected ([BiX_4/2]⁺)_n units. Since each Bi ion is surrounded by eight halogenide ions in a square-antiprismatic form, the structure can alternatively be described as consisting of chains of edge sharing ([BiX₄X_4/2]^3?)_n antiprisms connected by Au³⁺ ions.     

Metallderivate von Molekülverbindungen. III. Molekül- und Kristallstruktur des Lithium-bis (trimethylsilyl)-phosphids · DME und des Lithium-dihydrogenphosphids · DME

Metal Derivatives of Molecular Compounds. III. Molecular and Crystal Structure of Lithium bis(trimethylsilyl)phosphide · DME and of Lithium dihydrogenphosphide · DME Lithium bis(trimethylsilyl)phosphide · DME 1 prepared from tris(trimethylsilyl)-phosphine and lithium methanide [2, 4] in 1,2-dimethoxyethane

1 1,2-Dimethoxyethan (DME); Tetrahydrofuran (THF); Bis[2-(dimethylamino)ethyl]methyl-amin (PMDETA).

, crystallizes in the orthorhombic space group Pnnn {a = 881.1(9); b = 1308.5(9); c = 1563.4(9) pm at ?120 ± 3°C; Z = 4 formula units}, lithium dihydrogenphosphide · DME 2 [10] prepared from phosphine and lithium- n -butanide in the same solvent, in P2 ₁ 2 ₁ 2 ₁ {a = 671.8(1); b = 878.6(1); c = 1332.2(2) pm at ?120 ± 3°C; Z = 4 formula units}. X-ray structure determinations (R _w = 0.036/0.045) show the bis(trimethylsilyl) derivative 1 to be dimeric with a planar P? Li? P? Li ring (P? Li 256 pm; Li? P? Li 76°; P? Li? P 104°), and the dihydrogenphosphide 2 to be polymeric with a linear Li? P? Li fragment (P? Li 254 to 260 pm; Li? P? Li 177°; P? Li? P 118°). The shortened P? Si distance (221 pm) of compound 1 and the structure of the PH ₂ group in 2 are discussed in detail. Lithium obtains its preferred coordination number 4 by a chelation with one molecule of 1,2-dimethoxyethane (Li? O 202 to 204 pm).     

Polykationische Hg‐Pnictid‐Gerüste mit einer neuen Füllungsvariante in den Strukturen von Hg3As2TlCl3 und Hg3Sb2TlBr3

Polycationic Hg‐Pnictide Frameworks with a Novel Kind of Filling in the Structures of Hg₃As₂TlCl₃ and Hg₃Sb₂TlBr₃ Hg₃As₂TlCl₃ and Hg₃Sb₂TlBr₃ were prepared from mixtures of Hg₂X₂, HgX₂ (X = Cl, Br), As or Sb and Tl in sealed evacuated glass ampoules in temperature gradients 330 °C → 290 °C for Hg₃As₂TlCl₃ (red, transparent crystals) and 290 °C → 260 °C for Hg₃Sb₂TlBr₃ (black crystals). The structures of the diamagnetic compounds were determined based on single crystal X‐ray diffraction data. Both compounds crystallize isotypically in the orthorhombic space group Pbcm with Z = 4 and the lattice constants a = 629.2(5) pm, b = 1234.1(7) pm and c = 1224.8(9) pm for Hg₃As₂TlCl₃ and a = 661.0(4) pm, b = 1311.2(9) pm and c = 1307.1(2) pm for Hg₃Sb₂TlBr₃. The structures can be described either as a cubic closest packing of As₂/Sb₂ dumb‐bells and halide anions with all octahedral interstices filled with Hg²⁺ and Tl⁺, or as a polycationic framework (Hg₃Y₂)²⁺ (Y = As, Sb) consisting of pnictide‐pnictide dumbbells each connected by six Hg atoms to a three dimensional porous arrangement. The centers of the cavities are occupied by Tl⁺ ions which are coordinated by six halide ions in distorted octahedral form. These TlX₆ octahedra share corners in all directions in the motive of the ReO₃ structure type. This new structure type shows a close relationship to the cubic family of compounds of the general formula (Hg₆Y₄)[MX₆]X (Y = As, Sb; M = Mo, Ti, Bi, Sb; X = Cl, Br). The halide ions are connected to the Hg atoms of the polycationic network and to the Tl⁺ ions. Extended Hueckel calculations were used to explain the bonding character of the thallium–halide and mercury–halide bonds.     

Triorganoantimon- und Triorganobismutderivate von Carbonsäuren fünfgliedriger Heterocyclen Kristall- und Molekülstruktur von (C6H5)3Sb(O2C-2-C4H3S)2

Inhaltsübersicht. Triorganoantimon- und Triorganobismutdicarboxylate R₃M[O₂C(CH₂)ⁿ-2-C₄H₃X]₂ (M = Sb, R = CH₃, C₆H₁₁, C₆H₅, 4-CH₃OC₆H₄; M = Bi, R = C₆H₅, 4-CH₃C₆H₄; n = 0, X = O, S, NH, NCH₃. M = Sb, R = CH₃, C₆H₅; M = Bi, R = C₆H₅; n = 1, X = O, S. M = Sb, R = C₆H₁₁, n = 1, X = S; R = 4-FC₆H₄, n = 0, X = O, S, NCH₃; R = 2,4,6-(CH₃)₃C₆H₂, n = 0, X = O, S, NH) wurden durch Reaktionen von R₃Sb(OH)₂ (R = CH₃, C₆H₁₁, 2,4,6-(CH₃)₃C₆H₂), R₃SbO (R = C₆H₅, 4-CH₃OC₆H₄, 4-FC₆H₄) bzw. R₃BiCO₃ mit den entsprechenden fünfgliedrigen heterocyclischen Carbonsäuren 2-C₄H₃X(CH₂)_nCOOH dargestellt. Auf der Basis schwingungsspektroskopischer Daten wird für alle Verbindungen eine trigonal bipyramidale Umgebung vom M (zwei O-Atome von einzähnigen Carboxylatliganden in den apikalen, drei C-Atome von R in den äquatorialen Positionen) vorgeschlagen, ferner eine schwache Wechselwirkung zwischen O(=C) jeder Carboxylatgruppe und M. Die Kristallstrukturbestimmung von (C₆H₅)₃Sb(O₂C–2-C₄H₃S)₃ stützt diesen Vorschlag. Die Verbindung kristallisiert triklin [Raumgruppe P$1; a = 891,8(14), b = 1058,2(12), c = 1435,6(9) pm, α = 68,53(8), β = 85,47(9), γ = 85,99(11)°; Z = 2; d(ber.) = 1,607 Mg m^–3; V(Zelle) = 1255,6 ų; Strukturbestimmung anhand von 3947 unabhängigen Reflexen (F_o > 3σ(F²_o)), R(ungewichtet) = 0,037]. Sb bindet drei C₆H₅-Gruppen in der äquatorialen Ebene [mittlerer Abstand Sb–C: 211,1(5)pm] und zwei einzähnige Carboxylatliganden in den apikalen Positionen einer verzerrten trigonalen Bipyramide [mittlerer Abstand Sb–O: 212,0(4) pm]. Aus den relativ kurzen Sb – O(=C)-Abständen [274,4(4) und 294,9(4) pm] und aus der Aufweitung des dem O(=C)-Atom nächsten äquatorialen C–Sb–C-Winkels auf 145,9(2)° [andere C-Sb-C-Winkel: 104,4(2), 109,5(2)°] wird auf schwache Sb–O(=C)-Koordination geschlossen. Schließlich wird eine Korrelation zwischen dem (+, –)I-Effekt des Organoliganden R an M (M = Sb, Bi) und der Stärke der M–O(=C)-Koordination in den Dicarboxylaten R₃M[O₂C(CH₂)_n–2-C₄H₃X]₂ vorgeschlagen. Triorganoanümony and Triorganobismuth Derivatives of Carbonic Acids of Five-membered Heterocycles. Crystal and Molecular Structure of (C₆H₅)₃Sb(O₂C–2-C₄H₃S)₂ Triorganoantimony- and triorganobismuth dicarboxylates R₃M[O₂C(CH₂)_n–2-C₄H₃X]₂ (M = Sb, R = CH₃, C₆H₁₁, C₆H₅, 4-CH₃OC₆H₄; M = Bi, R = C₆H₅, 4-CH₃C₆H₄; n = 0, X = O, S, NH, NCH₃. M = Sb, R = CH₃, C₆H₅; M = Bi, R = C₆H₅; n = 1, X = O, S. M = Sb, R = C₆H₁₁, n = 1, X = S; R = 4-FC₆H₄, n = 0, X = O, S, NCH₃; R = 2,4,6-(CH₃)₃C₆H₂, n = 0, X = O, S, NH) have been prepared by reaction of R₃Sb(OH)₂ (R = CH₃, C₆H₁₁; 2,4,6-(CH₃)₃C₆H₂), R₃SbO (R = C₆H₅, 4-CH₃OC₆H₄, 4-FC₆H₄) or R₃BiCO₃ with the appropriate five-membered heterocyclic carboxylic acid. From vibrational data for all compounds a trigonal bipyramidal environment around M (two O atoms of unidendate carboxylate ligands in apical, three C atoms (of R) in equatorial positions) is proposed and also an additional weak interaction of O(=C) of each carboxylate group and M. The crystal structure determination of Ph₃Sb(O₂C–2-C₄H₃S)₂ gives additional prove to this proposal. It crystallizes triclinic [space group P$1; a = 891.8(14), b = 1058.2(12), c = 1435.6(9) pm, α = 68.53(8), β = 85.47(9), γ = 85.99(11)°; Z = 2; d(calc.) = 1.607 Mg m^–3; V_cell = 1255.6 ų; structure determination from 3 947 independent reflexions (F_o > 3σ(F²_o)), R(unweighted) = 0.037]. Sb is bonding to three C₆H₅ groups in the equatorial plane [mean distance Sb–C: 211.1(5) pm] and two unidentate carboxylate ligands in the apical positions of a distorted trigonal bipyramid [mean distance Sb–O: 212.0(4) pm]. From the relatively short Sb–O(=C) distances [274.4(4) and 294.9(4) pm] and from the enlarged value of the equatorial C–Sb–C angle next to the O(=C) atom [145.9(2)°; other C–Sb–C angles: 104.4(2), 109.5(2)°] additional weak Sb–O(=C) coordination is inferred. Finally a correlation between the (+, –) I-effect of the organic ligands It at M and the strength of the M–O = C interaction is suggested.     

Wasserstoffbrücken. I. Molekül- und KristallStruktur der Phosphonsäure H3PO3 – Röntgen- und Neutronenbeugungsuntersuchungen an der Hydrogen- und der Deuterium-Verbindung

Hydrogen Bridges. I. Molecular and Crystal Structure of Phosphonic Acid H₃PO₃ – X-ray and Neutron Diffraction Studies of the Hydrogen and Deuterium Compounds The structure of phosphonic acid H₃PO₃ has been redetermined by single crystal neutron diffraction (λ = 104.22 pm) at 15.0 ± 0.1 K yielding lattice parameters {Pna2₁; Z = 8; a = 716.6(3); b = 1201.3(5); c = 674.3(3) pm} and bond lengths {mean values from two crystallographically independent molecules: P? O 155; P?O 150; P? H 139; O? H 101 pm} of high reliability (R = 0.053). Each molecule is involved in four asymmetric hydrogen bonds (O…H 155 to 160pm; O? H…O 168 to 177°) with either hydroxyl group donating and the phosphoryl fragment acting as a twofold acceptor. Thus a complex, three-dimensional net, consisting of four- and eight-point circuits in a 1:2 ratio, is put up although the molecules are packed in a comparatively simple way to form an almost cubic closest arrangement. An X-ray crystal structure determination (R = 0.032) carried out at 173 ± 3 K for comparison revealed no significant differences and angles between phosphorus and oxygen atoms; an additional comparing neutron diffraction study at 15.0 ± 0.1 K (λ = 131.68 pm; isotropic atomic displacement parameters) of the hydrogen (r = 0.044) and deuterium compounds (R = 0.041) resulted in nearly identical structural models for the two isotopomers.     

Strukturelle Vielfalt im pseudo‐ternären System M/Ge/I: α‐[NMe(nBu)3](GeI4)I, β‐[NMe(nBu)3](GeI4)I und [ImMe(nBu)][N(nBu)4](GeI4)3I2

By reaction of GeI₄, [N(nBu)₄]I as iodide donor, and [NMe(nBu)₃][N(Tf)₂] as ionic liquid, reddish‐black, plate‐like shaped crystals are obtained. X‐ray diffraction analysis of single crystals resulted in the compositions ;alpha;‐[NMe(nBu)₃](GeI₄)I (Pbca; a = 1495.4(3) pm; b = 1940.6(4) pm; c = 3643.2(7) pm; Z = 16) and β‐[NMe(nBu)₃](GeI₄)I (Pn; a = 1141.5(2) pm; b = 953.6(2) pm; c = 1208.9(2) pm; β = 100.8(1)°; Z = 2). Depending on the reaction temperature, the one or other compound is formed selectively. In addition, the reaction of GeI₄ and [N(nBu)₄]I, using [ImMe(nBu)][BF₄] (Im = imidazole) as ionic liquid, resulted in the crystallization of [ImMe(nBu)][N(nBu)₄](GeI₄)₃I₂ (P2₁/c; a = 1641.2(3) pm; b = 1903.0(4) pm; c = 1867.7(4) pm; β = 92.0(1)°; Z = 4). The anionic network of all three compounds is established by molecular germanium(IV)iodide, which is bridged by iodide anions. The different connectivity of (GeI₄–I^–) networks is attributed to the flexibility of I^– regarding its coordination and bond length. Here, a [3+1]‐, 4‐ and 5‐fold coordination is first observed in the pseudo‐ternary system M/Ge/I (M: cation).     

Crystal Structure and Dimorphism of Silicon Tetraisocyanate Si(NCO)4

Silicon tetraisocyanate Si(NCO)₄ was obtained by reacting SiCl₄ and AgNCO in boiling toluene. The colourless liquid was analyzed by Raman and NMR spectroscopy. Structural studies on solid Si(NCO)₄ (melting point: +26 °C) have revealed it to exist in two polymorphic modifications. According to the results of single‐crystal X‐ray diffraction, at T = –173 °C, α‐Si(NCO)₄ exhibits triclinic symmetry (P$\bar{1}$ ; a = 10.05(5), b = 10.50(2), c = 14.32(1) Å, α = 91.62(1)°, β = 92, 32(1)°, γ = 99.68(1)°; V = 1488.56(3) ų; Z = 8). Above T = –33 °C, a monoclinic phase evolves, β‐Si(NCO)₄ (P2₁/c; a = 10.78(3), b = 7.11(1), c = 10.27(5) Å, β = 99, 06(9)°; V = 777.39(1) ų; Z = 4). The charge distribution was studied for both polymorphs. In the solid state, Si(NCO)₄ is a tetrahedral molecule with the Si–N=C=O linkages bent at the nitrogen atoms.     

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.     

Metallderivate von Molekülverbindungen. IV. Synthese,Struktur und Reaktivität des Lithium-[tris-(trimethylsilyl)silyl]tellanids · DME

Metal Derivatives of Molecular Compounds. IV Synthesis, Structure, and Reactivity of Lithium [Tris(trimethylsilyl)silyl]tellanide · DME Lithium tris(trimethylsilyl)silanide · 1,5 DME [3] and tellurium react in 1,2-dimethoxyethane to give colourless lithium [tris(trimethylsilyl)silyl]tellanide · DME ( 1 ). An X-ray structure determination {-150 · 3·C; P2₁/c; a = 1346.6(4); b = 1497.0(4); c = 1274.5(3) pm; β = 99.22(2)·; Z = 2 dimers; R = 0.030} shows the compound to be dimeric forming a planar Li? Te? Li? Te ring with two tris(trimethylsilyl)silyl substituents in a trans position. Three-coordinate tellurium is bound to the central silicon of the tris(trimethylsilyl)silyl group and to two lithium atoms; the two remaining sites of each four-coordinate lithium are occupied by the chelate ligand DME {Li? Te 278 and 284; Si? Te 250; Li? O 200 pm (2X); Te? Li? Te 105°; Li? Te? Li 75°; O? Li? O 84°}. The covalent radius of 154 pm as determined for the DME-complexed lithium in tellanide 1 is within the range of 155 ± 3 pm, also characteristic for similar compounds. In typical reactions of the tellanide 1 [tris(trimethylsilyl)silyl]tellane ( 2 ), methyl-[tris(trimethylsilyl)silyl]tellane ( 4 ) and bis[tris(trimethylsilyl)silyl]ditellane ( 5 ) are formed.     

Element-Element-Bindungen. II. Synthese und Struktur eines anellierten Tetrastibaadamantans,dargestellt aus Antimon(III)-chlorid und Natrium-cyclopentadienid

Element-Element Bonds. II. Synthesis and Structure of an Anellated Tetrastibaadamantane, Formed by Antimony(III) Chloride and Sodium Cyclopentadienide Revising the reaction between antimony(III) chloride and sodium cyclopentadienide in tetrahydrofuran (THF), originally published by FISCHER und SCHREINER [3], we could not verify the stated formation of tetra(cyclopentadienyl)distibane being red both in the solid and in solution. The pale yellow compound isolated instead is sodium [18-cyclopenta-2,4-dienyl-4,8,12-cyclopenta-2,4-diene-1,1,2-triyl-3a,8a-epistibino-tricyclopenta[1,4,7]tristiboninide] = 3 tetrahydrofuran 1 . Shown by an x-ray crystal structure determination (?45°C; monoclinic; Cc; a = 1882.7(9); b = 1183.5(5); c = 1733.8(13) pm; β = 93.38(5)°; Z = 4; R = 0.043) three (μ₃-C₅H₃) units together with four antimony atoms build up a tetrastibaadamantane framework with a (σ-C₅H₅) and a (μ₂-C₅H₃^?) group as additional substituents. Nearly centric above the anionic ring a sodium cation coordinated by three THF molecules is placed. Characteristic bond lengths and angles lie in the following ranges: Sb? C(sp²) 212–216; Sb? C(sp³) 216–228; Na? C 270–284; Na? O 226–235 pm; C? Sb? C 91–97; Sb? C? Sb 109–110°. ¹H and ¹³C-{¹H} n.m.r. spectra are discussed; the ion pair 1 shows a degenerate valency tautomerism in solution.     

Synthese und Charakterisierung von Natriumcyanamid

Synthesis and Characterization of Sodium Cyanamide The synthesis of Na₂CN₂ was carried out by reaction of sodium amide with sodium hydrogen cyanamide at 200 °C, in vacuum. Single crystals were obtained while heating the product (500 °C, 8 days) in silver crucibles. The title compound was characterised by single crystal X‐ray diffraction and IR‐spectroscopy (C2/m; Z = 2, a = 5.0456(3), b = 5.0010(3), c = 5.5359(3) Å; β = 110.078(5)°; R1 = 3.18%, wR2 = 6.35%, GOF = 1.078). The CN₂^2– units are linear exhibiting a C–N bond length of 1.236(1) Å, while sodium is coordinated by five nitrogen atoms forming a square pyramid. The structural relationships to aristotypic Na₂HgO₂ are pointed out.     

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.     

Über Kaliumtetracyanoplatinat(II), Kaliumtetracyanopalladat(II) und deren Monohydrate

We have determined the crystal structures of the potassium tetracyanoplatinates(II) and ‐palladates(II), and of their monohydrates, by X‐ray powder diffraction techniques and single crystal structure analysis. K₂[Pt(CN)₄]: orthorhombic; Pccn; a = 1370.11(2); b = 907.09(1); c = 703.91(2) pm; Z = 4; R_F² = 0.0903 (N(hkl) = 415). K₂[Pt(CN)₄] · H₂O: orthorhombic; Pnna; a = 715.79(4); b = 977.91(6); c = 1322.46(8) pm; Z = 4; R(F)_N′ = 0.027 (N′(hkl) = 1066). K₂[Pd(CN)₄]: monoclinic; P2₁/c; a = 433.03(2); b = 782.90(3); c = 1328.17(6) pm; ß = 93.069(3)°; Z = 2; R_p = 0.0583 (N(hkl) = 352). K₂[Pd(CN)₄] · H₂O: orthorhombic; Pnna; a = 721.48(6); b = 976.77(8); c = 1326.4(1) pm; Z = 4; R(F)_N′ = 0.048 (N′(hkl) = 1137). In all examined representatives the anions are stacked one upon the other, even though they are tilted in part. The results are completed by spectroscopic and thermo analytical investigations.