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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 1329-1338 
    ISSN: 0044-2313
    Keywords: Nb6I11-xBrx (0 ≤ x ≤ 2.7) ; spin-crossover ; phase transition ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthese, Struktur und Spin-crossover-Übergang der Clusterverbindung Nb6I11-xBrx (0 ≤ x ≤ 2,7)Mischkristalle Nb6I11-xBrx (0 ≤ x ≤ 2,7) werden aus Nb3Br8, Nb3I8 und Nb in zugeschmolzenen Nb-Ampullen bei 1 130 K dargestellt. Wie für Nb6I11 selbst wird auch im Mischkristall eine Phasentransformation zweiter Ordnung mit einem Wechsel der Raumgruppe von P21cn (tiefe Temperatur) nach Pccn gefunden, die von einem Spin-crossover-Übergang vom Dublett- zum Quartett-Zustand begleitet wird. Mit steigendem Br-Gehalt werden die Gitterkonstanten kleiner und die Umwandlungstemperatur verschiebt sich von 274 K nach 170 K bei gleichzeitiger Verbreiterung des Transformationsintervalles. Einkristalluntersuchungen für x = 0,5 und 2,3, jeweils bei 110 K und 298 K durchgeführt, ergeben eine bevorzugte Substitution für eines der verbrückenden Jodatome (I6).
    Notes: The homogeneous phase Nb6I11-xBrx (0 ≤ x ≤ 2.7) is synthesized from Nb3Br8, Nb3I8 and Nb in sealed Nb capsules at 1 130 K. A second-order phase transition is found as for the composition Nb6I11 itself, changing the space group from P21cn (low temperatures) to Pccn, accompanied by a spin-crossover from a doublet to a quartet state. With increasing Br content the lattice constants decrease and the transition temperature shifts from 274 to 170 K while the transition interval is broadened simultaneously. Single crystal investigations for x = 0.5 and 2.3, each at 110 and 298 K, indicate a preferred substitution of one of the bridging I positions (I6) by Br atoms.
    Additional Material: 6 Ill.
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  • 2
    ISSN: 0009-2940
    Keywords: cis-Stannyl-boryl-alkenes ; Sulfur diimide anions ; Multinuclear NMR ; 1,2,5-Azastannaboratoles ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis of 1,2,5-Azastannaborole Derivatives from Sulfur Diimide Anions and cis-Stannyl-boryl-alkenes - X-ray Crystallographic Study of Two 2,5-Dihydro-1-(imino-λ4-sulfanylidene)-1,2,5-azastannaboratoles(E)-3-(Diethylboryl)-2-(chlorodimethylstannyl)-2-pentene (1) reacts with the sulfur diimide anions 3 [R - NSN-K+, R=tBu (a), Me3Si (b), tBu2P (c)] in a 1:1 ratio, and with 4 (K+;-NSN-K+) in a 2:1 ratio, to give various heterocycles. The first products of the reaction between 1 and 3 [2,5-dihydro-1-(imino-λ4-sulfanylidene)-1,2,5-azastannaboratoles 5a, b, c] are isolated at -30°C and characterized by X-ray crystallography. The compounds 5a,b rearrange into the borole derivates 6a,b (with an additional N—Sn coordination) by transfer of an ethyl group from the boron to the sulfur atom. Ethylene is eliminated from compound 6a (not 6b) to give the diaminosulfane derivative 7a. The 2:1 reaction between 1 and 4 affords an unstable intermediate 8 with a fluxional structure, leading to 9 in which an EtS moiety bridges a borole ring (analogous to 6 but without the additional N - Sn coordination) and a boratole ring (analogous to 5). All compounds are characterized by 1H-, 11B-, 13C-, 15N- (in part), 29Si- and 119Sn-NMR spectra.
    Additional Material: 2 Ill.
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 124 (1991), S. 427-432 
    ISSN: 0009-2940
    Keywords: Chalcogenoboron hydride structure ; Adamantane ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: [(BH6)2]S4]2-, [(BH2)Se4]2-: New Chalcogenoboron Hydride Anions with Adamantane StructureThe reaction of THF·BH3/NaBH4 (2: 1) with H2S produces Na[H3B-μ2-S(B2H5)] (5) with hydrogen evolution. 5 reacts with an excess of H2S to give Na2[(BH2)6S4] (3a), which is also formed in the reaction of THF·BH3 with NaSH or anhydrous Na2S. These reactions proceed via 5 and the intermediates 7 or 8 by loss of BH-4 and cyclization. The analogous compound Na2[(BH2)6Se4] (4a) is obtained by the reaction of elemental selenium with NaBH4 (1:1) in triglyme. The primary product is Na2[H3B-Se-Se-BH3] (9). Treatment of 9 at 100 - 110°C yields 4a and polymers, 3a and 4a react with CsBr to form the crystalline compounds Cs2[(BH2)6Se4]·CsBr (3b) and Cs2-[(BH2)6Se4]·CsBr (4b), characterized by X-ray structure determinations. The anions of 3b and 4b consist of an adamantane skeleton. The Br- ion is octahedrally coordinated by Cs+ ions. The Cs6Br octahedra share faces to form columns along the hexagonal c axis. The crystal structures of the isotypic compounds 3b and 4b are closely related to the structure of CsNiCl3.
    Additional Material: 3 Ill.
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  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 123 (1990), S. 75-77 
    ISSN: 0009-2940
    Keywords: Diaminosulfanes / Disilanes / Sulfur diimides ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A New Route to N-Silylated Diaminosulfanes: The Splitting of the Si — Si Bond in Disilanes by Sulfur DiimidesSulfur diimides (R1N)S(N2) (R1, R2 = tBu, SiMe3; 1a-c) and disilanes Cl2(R)Si-Si(R)Cl2 [R = Me (2), Cl (3)] react fast and quantitatively in a 1:1 ratio to give diaminosulfanes (4, 5) by cleavage of the Si-Si bond. The solid-state structure of tBu(SiMeCl2)N-S-N(SiMe3)SiMeCl2 (4b) has been studied both by X-ray crystallography and 29Si-NMR spectroscopy.
    Additional Material: 1 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 612 (1992), S. 56-62 
    ISSN: 0044-2313
    Keywords: 1λ5,3λ5-diphosphete ; addition compounds with GeCl2, SnCl2, (CO)5W(Z-cyclooctene) ; n.m.r., i.r., mass spectra ; X-ray structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: 1,1,3,3-Tetrakis(dimethylamino)-1λ5,3λ5-diphosphete as Ligand in Coordination Compounds1,1,3,3-Tetrakis(dimethylamino)-1λ5,3λ5-diphosphete, 1, reacts with GeCl2 · 1,4-dioxane, SnCl2, and (CO)5W(Z-cyclooctene) to give the complexes {HCP[N(CH3)2]2}2 · GeCl2, 3, {HCP[N(CH3)2]2}2 · SnCl2, 4, and {HCP[N(CH3)2]2}2 · W(CO)5, 5, respectively. The n.m.r., mass, and i.r. spectra of the new compounds as well as the crystal and molecular structures of 3 and 4 are reported and the bonding situation in compounds 3-5 is discussed.
    Notes: 1,1,3,3-Tetrakis(dimethylamino)-1λ5,3λ5-diphosphet, 1 bildet mit GeCl2 · 1,4-Dioxan, SnCl2 bzw. (CO)5W(Z-cycloocten) die komplexe {HCP[N(CH3)2]2}2 · GeCl2, 3, {HCP[N(CH3)2]2}2 · SnCl2, 4, bzw. {HCP[N(CH3)2]2}2 · W(CO)5, 5. Die NMR-, Massen- und IR-Spektren der neuen Verbindungen sowie die Kristall- und Molekülstruktur von 3 und 4 werden mitgeteilt und die Bindungsverhältnisse in den Verbindungen 3-5 diskutiert.
    Additional Material: 3 Ill.
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  • 6
    ISSN: 0044-2313
    Keywords: Gadolinium Iodide Carbide Nitride ; Gadolinium Bromide Carbide Nitride ; Yttrium Iodide Carbide Nitride ; Lanthanum Iodide Carbide Nitride ; preparation ; X-ray single crystal structure investigation ; crystal structure ; condensed cluster ; chain of condensed octahedra and double tetrahedra ; C—C single bond ; Gd6(C2) octahedron ; Gd6N2 double tetrahedron ; Y10(C2)2 double octahedron ; Y6N2 double tetrahedron ; α-Gd4I6CN, β-Gd4I6CN, Y6I9C2N, α-Gd4Br6CN, α-La4I6CN ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Gd4I6CN: A Carbide Nitride with Chains of Gd6(C2) Octahedra and Gd6N2 Double TetrahedraThe compound α-Gd4I6CN is prepared by reaction of Gd, GdI3, C, and GdN (1:2:1:1 mole ratio) at 1 170 K in sealed Ta tubes. It is obtained as brown red, transparent needles which are air and moisture sensitive. The structure of α-Gd4I6CN contains Gd6 octahedra centered by C2 groups and double tetrahedra centered by N atoms. The units are alternatingly connected via common edges to form chains (Gd2Gd4/2C2) (Gd2/2Gd2/2N)2 parallel [001]. The linear chains are surrounded by I atoms above all free edges of the metal polyhedra and linked according to (Gd2Gd4/2C2) (Gd2Gd4/2N2)I4/2I8I2 in the a - b plane.We also found β-Gd4I6CN, which is formed in a monotropic transition from the α-form. In the structure the chains of Gd octahedra and tetrahedra as described for α-Gd4I6CN are more densely packed.The structure of Y6I9C2N is composed by chains of pairs of Y-octahedra and Y-tetrahedra, respectively. The octahedra are centered by C2 groups, the tetrahedra by N-atoms.We also synthesized the compounds Gd4Br6CN und La4I6CN by tempering at 1 220 K. They are isotypic with α-Gd4I6CN.
    Notes: α-Gd4I6CN wird durch Reaktion von Gd, GdI3, C und GdN (Molverhältnis 1:2:1:1) bei 1 170 K im verschlossenen Ta-Tiegel erhalten. Es bildet braunrot durchscheinende Nadeln, die gegen Luft und Feuchtigkeit empfindlich sind. Die Struktur von α-Gd4I6CN enthält durch C2-Einheiten zentrierte Gd6-Oktaeder und Doppel aus N zentrierten Tetraedern, Gd6N2. Abwechselnd sind Oktaeder und Tetraederdoppel über gemeinsame Kanten zu Ketten (Gd2Gd4/2C2) (Gd2/2Gd2/2N)2 verknüpft, die parallel [001] ausgerichtet sind. Diese eindimensionalen Einheiten sind über allen freien Kanten durch Iodatome koordiniert und untereinander nach dem Schema (Gd2Gd4/2C2) · (Gd2Gd4/2N2)I4/2I8I2 in der a - b-Ebene verknüpft.Daneben existiert noch ein β-Gd4I6CN, das sich monotrop aus der α-Form bei 1 300 K bildet. Dessen Struktur zeichnet sich durch eine dichtere Packung der für die α-Form beschriebenen Gd-Oktaeder-Tetraederketten aus.In der Struktur von Y6I9C2N sind die Ketten aus Doppeln sowohl C2-zentrierter Oktaeder als auch N-zentrierter Tetraeder der Y-Atome aufgebaut.Weiter erhielten wir die mit α-Gd4I6CN isotypen Verbindungen Gd4Br6CN und La4I6CN durch Tempern der Ausgangsverbindungen bei 1 220 K.
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