Showing papers by "Bernt Krebs published in 1981"

Ein Beitrag zu den Koordinationsverhältnissen in den gasförmigen MAI2Cl8‐Komplexen Das Spektrum von CoAl2ClnI8–n und die Kristallstruktur von PdAl2Cl8

Abstract: Das fur gasformige halogen-gemischte Komplexe CoAl2ClnI8–n gemessene Spektrum liegt auf der Skala der Wellenzahlen zwischen denen von CoAl2Cl8 und CoAl2I8. Die molare Extinktion ist in allen drei Fallen von vergleichbarer Grose. Daraus ist zu schliesen, das die Koordination des Kobalts durch Halogen bei diesen Verbindungen verzerrt oktaedrisch ist. Die Kristallstruktur von PdAl2Cl8 wurde mit Einkristallen bestimmt. Die Verbindung kristallisiert monoklin mit a = 6,583(3), b = 7,342(3), c = 13,033(5) A, β = 96,40(3)°; Raumgruppe P21/c. Es liegt ein Molekelgitter mit 2 PdAl2Cl8-Molekeln/Zelle vor. Pd ist quadratisch-planar von Cl umgeben. Das Remissionsspektrum des festen PdAl2Cl8 stimmt mit dem Absorptionsspektrum der gasformigen Verbindung uberein. Die Kristallstrukturen der Verbindungen MAl2Cl8, insbesondere der Zusammenhang der Struktur der Gasmolekel CoAl2Cl8 mit der bekannten Kristallstruktur dieser Verbindung werden behandelt. A Contribution to the Coordination in the Gaseous MAl2Cl8 Complexes. Visible Spectrum of CoAl2ClnI8–n and Crystal Structure of PdAl2Cl8 The band wavenumbers in the visible spectrum of the mixed halogen complexes CoAl2ClnI8–n are observed between those of CoAl2Cl8 and CoAl2I8. The molar extinctions are comparable for all three cases. It can be concluded that the halogen coordination around cobalt is distorted octahedral. The crystal structure of PdAl2Cl8 was determined from single crystals. The compound is monoclinic, space group P21/c, with a = 6,583(3), b = 7.342(3), c = 13.033(5) A, β = 96.40(3)°. The structure contains two molecular PdAl2Cl8 units per cell. Pd is in a tetragonal planar coordination of 4 Cl. The remissionspectrum of solid PdAl2Cl8 corresponds to the spectrum of the gaseous compound. The crystal structures of the compounds MAl2Cl8 are discussed, especially the relationship of the structure of the gaseous molecule CoAl2Cl8 with the known crystal structure of this compound.

Salze des S4N4O2 – Beispiele für die Abhängigkeit de Struktur von cyclischen Schwefel‐Stickstoff‐Verbindungen von der Elektronendichte

Abstract: Die Umsetzung von S4N4O2 mit Nucleophilen (Alkoholate, Alkohole, Azide und Isocyanate) in alkoholischem Medium fuhrt zu den Salzen 1a–h. Fur 1h wurde eine Rontgenstrukturanalyse durchgefuhrt. 1h kristallisiert in der Raumgruppe P21/n und enthalt eine transannulare SS Bindung mit 248.2 (2) pm. Die Struktur von 1h wird im Zusammenhang mit der Zunahme der Elektronendichte betrachtet und mit den Ergebnissen der Rontgenstrukturanalyse von CH3Si(NSN)3SiCH3 (2) verglichen. 2 kristallisiert kubisch (Raumgruppe P4132). Das bicyclische Molekul (SN 150.4 (2), SiN 173.7 (2)pm) hat praktisch D3h Symmetrie und zeigt keine SS-Bindungen im Ring. Salts of S4N4O2 – Examples for the Dependence of the Structure of Cyclic Sulfur-Nitrogen Compounds on the Electron Density The reaction of S4N4O2 with nucleophiles (alcoholates, alcohols, azides, and isocyanates) in alcoholic solution leads to the salts 1a–h. The Structure of 1h was determined by means of an X-ray analysis. 1h crystallizes in the space group P21/n and contains a transannular SS-bond with 248.2 (2) pm. The structure of 1h is considered in connection with the increase of electron density and compared with the results of the X-ray analysis of CH3Si(NSN)3SiCH3 (2). 2 is cubic (space group P4132). The bicyclic molecule (SN 150.4(2), SiN 173.7 (2) pm) has approximate D3h symmetry and shows no SS bonds across the rings.

Sulfidhalogenide des Germaniums: Darstellung und Strukturen von Ge4S6Br4 und Ge4S6I4 / Thiohalides of Germanium: Preparation and Structures of Ge4SeBr4 and Ge4S6I4

Abstract: The reaction of GeX₄ (X = Br, I) and H₂S in CS₂ yields Ge₄S₆Br₄ (1) and Ge₄S₆I₄ (2). The crystal structures of 1 and 2 were determined from single crystal X-ray data (1: P1, a = 880.6, b = 993.4, c = 1010.6 pm, α = 86.05, β = 64.00, γ = 89.87°, V = 792 · 10⁶ pm ³ , Z = 2; 2 : P3, a = 1064.0, c = 946.1 pm, V = 928 · 10⁶ pm³ , Z = 2). They consist of isolated adamantane-like molecules.

Thio-hydroxoanionen des Germaniums: Darstellung, Struktur und Eigenschaften von Na2GeS2(OH)2 · 5 H2O / Thio-hydroxo Anions of Germanium: Preparation, Structure and Properties of Na2GeS2(OH)2 · 5 H2O

Abstract: Pure thio-hydroxo-germanates can be prepared from aqueous solutions by reactions of stoichiometric amounts of either sodium sulfide and GeO₂, or NaOH and GeS₂. The preparation of colourless crystalline Na₂GeS₂(OH)₂ · 5 H₂O is reported. The compound is characterized by a single-crystal X-ray structure analysis. It is orthorhombic, space group Pbcn, with a = 10.752(2), b= 13.787(2), c = 14.150(2) A. The structure contains novel monomeric GeS₂(OH)₂²⁻ anions with Ge-S bond distances of 2.150(1) and 2.145(1) A and with Ge-O lengths of 1.809(3) and 1.815(3) A. An extensive S ··· HO-and O -HO-hydrogen bond system connects the anions with the octahedrally coordinated Na⁺ ions. The vibrational spectra are reported. The symmetric GeS₂ andGeO₂ stretching vibrations in the anion are observed at 415 and 618 cm⁻¹.

Alkoxohalogenotellurate(IV): Darstellung und Struktur von Tetraphenylphosphonium-trichloro(dioxo-ethylen-O.O')tellurat(rV) / Alkoxohalogenotellurates(IV): Preparation and Structure of Tetraphenylphosphonium Trichloro(dioxo-ethylene-O,O')tellurate(IV)

Abstract: Abstract The deprotonated glycolate dianion (OCH2CH2O)2- is shown to react as a bidentate chelating ligand towards chalcogen(IV) halides. With TeCl4, the anion TeCl3(O2C2H4)- is formed. According to a single crystal X-ray analysis of the tetraphenylphosphonium salt (P21/c, a = 7.501, b = 26.328, c = 13.582 A, β= 104.55°, Z = 4) Te is in a tetragonal pyramidal (ψ octahedral) coordination with the alcoholate ligands in the apical (Te-O 1.919 Å) and in one of the equatorial positions (Te O 1.973 Å), the Te-Cl bond lengths being between 2.495 and 2.590 Å. The trans bond lengthening effect of the equatorial alcoholate ligand (i.e. the polarizing effect towards the lone pair) is unusually low. Vibrational spectra are reported.

Cyclodiaza - λ6-thiane / Cyclodiaza-λ6-thianes

Abstract: Abstract From sulfurtriimides and N-perfluoroalkyl-isocyanates or -sulfinyl-amines SSS′S′-tetra-imino-(11 a-c), SS′-dioxo-SS′-di-imino-(19 and 28), and SSS′-tri-oxo-S′-imino-cyclodiaza-λ6 -thianes (34) were prepared. The structures of 11 b, 19 and 28 are discussed, general rules for the stability of these ring systems are derived.

Synthese und Röntgenstrukturanalyse von S4N4‐Derivaten mit drei‐ und vierfach koordinierten Schwefelatomen

Abstract: CF3SO2NSCl2 reagiert mit (CH3)2S[NSi(CH3)3]2, (C4H8)S[NSi(CH3)3]2 oder (C5H10)S[NSi(CH3)3]2 unter Trimethylchlorsilanabspaltung zu den achtgliedrigen S4N4-Derivaten S4N4(NSO2CF3)2(CH3)43, S4N4(NSO2CF3)2(C4H8)24a und S4N4(NSO2CF3)2(C5H1 0)24b. In den achtgliedrigen SN-Ringen haben die Schwefelatome die Koordinationszahl 3 und 4. Die Rontgenstrukturanalyse von 4a ergab eine Sessel-Konformation. 4a kristallisiert orthorhombisch in der Raumgruppe Pna21 mit a = 17,641(4), b = 6,406(2), c = 19,130(4) A, dx = 1,815 g cm−3 und Z = 4. Die mittleren SN-Abstande betragen an den vierfach koordinierten Schwefelatomen 1,597 A und an den Schwefelatomen mit der Koordinationszahl 3 1,650 A. CF3SO2NSCl2 reagiert mit trimethylzinnhaltigen SN-Verbindungen zum bekannten CF3SO2N[Sn(CH3)3]S(CH3)NSO2CF3 und Dimethylzinndichlorid. Synthesis and X-Ray Structure Analysis of S4N4-Derivatives with Threefold and Fourfold Coordinated Sulfur Atoms CF3SO2NSCl2 reacts with (CH3)2S[NSi(CH3)3]2, (C4H8)S[NSi(CH3)3]2 or (C5H10S[NSi(CH3)2]2 under elimination of (CH3)3SiCl to yield the eight-membered S4N4 derivatives S4N4−NSO2CF3)2(CH3)4, 3, S4N4(NSO2CF3)2(C4H8)24a und S4N4(NSO2CF3)2(C5H1 0)24b. In the eight-membered SN-rings the sulfur atoms have the coordination number 3 and 4. The X-ray structure analysis of 4a revealed a chair conformation. 4a crystallizes in the orthorhombic space group Pna21 with a = 17.641(4), b = 6.406(2), c = 19.130(4) A, dx = 1.815 g cm−3, and Z = 4. The average SN distance was found to be 1.597 A at fourfold coordinated sulfur atoms and 1.650 A at sulfur with coordination number 3. CF3SO2N=SCl2 reacts with trimethyl tin-containing SN compounds to the known CF3SO2N[Sn(CH3)3]S(CH3)NSO2CF3 and dimethyl tin dichloride.