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1Author    EdwardW. Abel, StuartA. Mucklejohn, T.Stanley Cameron, RuthE. CordesRequires cookie*
 Title    The Dimeric Phosphinimine Complex [CdI2(HN: PPh3)2]2 Containing N-H --I Hydrogen Bonds  
  Reference    Z. Naturforsch. 33b, 339—340 (1978); received December 5 1977 
  Published    1978 
  Keywords    X-ray, Crystal Structure, Phosphinimine 
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 TEI-XML for    default:Reihe_B/33/ZNB-1978-33b-0339_n.pdf 
 Identifier    ZNB-1978-33b-0339_n 
 Volume    33 
2Author    W. Stoeger, A. RabenauRequires cookie*
 Title    Tl6Ag2Iio9 ein Polyiodid mit Ag2-Paaren Darstellung, Eigenschaften und Kristallstruktur Tl6Ag2Iio, a Polyiodide with Ag2 Pairs Preparation, Properties, and Crystal Structure  
 Abstract    TleAg2Iio forms hexagonal crystals with metallic luster. Under its own I2-pressure the m.p. is 302 °C. In vacuum or under inert gas TleAg2Iio decomposes above 170 °C forming 1 mole of I2. The space group is P62c with the lattice constants a = 10.480 A, c = 13.415 A and Z = 2. TleAg2Iio is built up by a framework of TIöIö with channels parallel to the c-axis. These channels contain Ag2 pairs with an Ag-Ag distance of 2.98 A and I| _ -polyiodide ions, respectively. 
  Reference    Z. Naturforsch. 33b, 740—744 (1978); eingegangen am 21. April 1978 
  Published    1978 
  Keywords    X-ray, Structure Determination, Polyhalides 
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 TEI-XML for    default:Reihe_B/33/ZNB-1978-33b-0740.pdf 
 Identifier    ZNB-1978-33b-0740 
 Volume    33 
3Author    G. Struckmeier, J. Engel, U. ThewaltRequires cookie*
 Title    Molekül-und Kristallstruktur des 5.5' -Diethoxycarbonyl-3.3' -diethyl-4.4' -dimethyl-pyrromethen-hydrobromids Crystal and Molecular Structure of 5,5'-Diethoxycarbonyl-3,3'-chethyl-4,4'-cÜmethyl-pyiTomethene Hydrobromide  
 Abstract    The crystal and molecular structure of the title compound has been determined by X-ray diffraction. The compound possesses an (almost) planar Z configuration. The ions form ion pairs in the solid state: each bromide anion is connected via two hydrogen bonds with a cation. The crystal data are: space group P2i/n with Z = 4; cell dimensions a = 14.097(2), b = 11.591(2), c = 14.133(3) A, ß = 106,22(2)°. 
  Reference    Z. Naturforsch. 33b, 753—755 (1978); eingegangen am 12. April 1978 
  Published    1978 
  Keywords    Pyrromethenes, X-ray, Molecular Structure 
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 TEI-XML for    default:Reihe_B/33/ZNB-1978-33b-0753.pdf 
 Identifier    ZNB-1978-33b-0753 
 Volume    33 
4Author    Dieter WeberRequires cookie*
 Title    CHsNHsSnBraJa-z = 0-3), a Sn(II)-System with Cubic Perovskite Structure  
 Abstract    CH3NH3SnBr^l3 -.x [x = 0—3) has the cubic perovskite structure with the unit cell parameters a = 5.89 A {x = 3), a = 6.01 A (x = 2) and a = 6.24 A (x = 0) and Z = 1. The compounds show intense colour and conducting property. The U9 Sn Mössbauer data are consistent with the high symmetry environment of the Sn(II)-ion. A bonding model, using a "p-resonance-bonding", can explain the properties of the cubic system. The synthesis is described. 
  Reference    Z. Naturforsch. 33b, 862—865 (1978); eingegangen am 5. Mai 1978 
  Published    1978 
  Keywords    Synthesis, X-ray, Mössbauer Spectra 
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 TEI-XML for    default:Reihe_B/33/ZNB-1978-33b-0862.pdf 
 Identifier    ZNB-1978-33b-0862 
 Volume    33 
5Author    F. Fehér, B. EngelenRequires cookie*
 Title    Beiträge zur Chemie des Schwefels, 116 [1] Kristall-und Molekülstrukturen von und 3-Methyl- Contributions to the Chemistry of Sulfur, 116 [1] Crystal and Molecular Structures of 1,2,4,5-Benzotetrathiepine and 3-Methyl-1,2,4,5-benzotetrathi  
 Abstract    The structures of 1,2,4,5-benzotetrathiepine and 3-methyl-l,2,4,5-benzotetrathiepine were determined by X-ray structure analysis. The constitution of the molecules, which was proposed by way of spectroscopic data, could be verified. The conformation of the seven-membered rings is the chair form. The position of the methyl group in 3-methyl-1,2,4,5-benzotetrathiepine is equatorial with respect to the seven-membered ring. Details of the conformations are discussed. Bond distances and angles are compared with those in other molecules, which have similar structures. 
  Reference    Z. Naturforsch. 34b, 426—430 (1979); eingegangen am 18. Oktober 1978 
  Published    1979 
  Keywords    X-ray, Cyclosulfanes, Conformation 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0426.pdf 
 Identifier    ZNB-1979-34b-0426 
 Volume    34 
6Author    Paul Binger, MichaelJ. Doyle, Carl Krüger, Yi-Hung TsayRequires cookie*
 Title    Metallacycloalkane, III [1] Darstellung und Charakterisierung von a.a'-Dipyridyl-Nickelacyclopentan Preparation and Characterisation of a,a'-Bipyridyl-nickelacyclopentane  
 Abstract    The title compound was synthesised from bis-l,5-cyclooctadienenickel, a,a'-bipyridyl and 1,4-dibromobutane in 83% yield and its structure determined by X-ray diffraction (a = 16.600, b = 10.837, c = 14.815 Ä; ß = 153.05°; C2/c, Z = 4; symmetry: C2 with square planar coordinated nickel; Ni-C: 1.949 A). a,a'-Bipyridylnickelcyclopentane reacts with maleic anhydride or methylacrylate under reductive elimination to give cyclobutane in 75 and 57% yield; considerable amounts of butenes are formed, in addition to cyclobutane, upon reaction with borontrifluoride-dibutylether or on thermolysis. 
  Reference    Z. Naturforsch. 34b, 1289—1292 (1979); eingegangen am 16. Mai 1979 
  Published    1979 
  Keywords    Nickelacyclopentane, Preparation, Metallacycloalkane, X-ray 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-1289.pdf 
 Identifier    ZNB-1979-34b-1289 
 Volume    34 
7Author    B. Engelen, C. FreiburgRequires cookie*
 Title    Kristallstruktur von Mangan(II)sulfit-Trihydrat, a-MnS03 * 3 H20 Crystal Structure of Manganese(II)sulfite Trihydrate, a-MnS03 * 3 H2O  
 Abstract    The structure of a-MnS03 • 3 H20, space group P2i/n, Z = 4, Dm = 2.42, Dx = 2.425gcm-3, a = 6.6501(3), b = 8.9065(4), c = 8.7925(4) Ä, ß=* 96.105(3)°, was solved by the Patterson method and refined by Fourier and least-squares methods. All H atoms were located. The final R's are 2.1/3.2% for the 1749 observed/2280 measured reflexions. Coordination of Mn is octahedral involving O atoms from three water molecules and three different sulfite groups. MnOß octahedra are linked through sulfite sulfur. The Mn-0 distances range from 2.149(2) to 2.314(2) A. The S-0 distances of the sulfite group are 1.529(2), 1.529(2) and 1.544(2) A. The first two are elongated by one, the latter by two H bonds. The O-S-O angles are 103.25(9), 104.18(9) and 104.35(9)°. 
  Reference    Z. Naturforsch. 34b, 1495—1499 (1979); eingegangen am 9. Juli 1979 
  Published    1979 
  Keywords    X-ray, Sulfites, Sulfite Hydrates 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-1495.pdf 
 Identifier    ZNB-1979-34b-1495 
 Volume    34 
8Author    Hans Siebert, Walther JentschRequires cookie*
 Title    Rhombohedrally Crystallizing Zinc Hexacyanometalates(III) Zn3[M(CN)e]2  
 Abstract    The preparation of a non-cubic modification of water-free hexacyanometalates(III) Zn3[M(CN)6]2 (M = Cr, Fe, Co) is described. The X-ray powder diagrams of these compounds have been indexed rhombohedrally, space group Dgd-R"3c, Z = 2. 
  Reference    (Z. Naturforsch. 36b, 123—124 [1981]; eingegangen am 17. September 1980) 
  Published    1981 
  Keywords    X-ray, Zinc, Cyanometalates 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0123_n.pdf 
 Identifier    ZNB-1981-36b-0123_n 
 Volume    36 
9Author    Barbara Balbach, Reinhold Alt, ManfredL. ZieglerRequires cookie*
 Title    Structural Investigations on Four-Membered Ring Systems, III* Crystal and Molecular Structures of frattS-2,4-Bis(trimethylsilyl)-2,4-dihydro-l,3-dithietane-, 2,2,4,4-Tetramethyl-3-pyrrolidinocyclobutanone and  
 Abstract    The molecular structures of the title compounds have been determined by X-ray methods. In the bis(trimethylsilyl) substituted dithietane the (CH3)3Si groups are in trans position; the C2S2-ring is planar. In the cyclobutanone the pyrrolidine group occupies an equatorial position, as does the phenyl group in the cyclobutanol. In the latter the hydroxyl group is trans to the pyrrolidine ring. The four-membered carbon rings are folded. 
  Reference    Z. Naturforsch. 37b, 1005—1013 (1982); eingegangen am 6. April 1982 
  Published    1982 
  Keywords    X-ray, Cyclobutanol, Dithietanetetroxide 
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 TEI-XML for    default:Reihe_B/37/ZNB-1982-37b-1005.pdf 
 Identifier    ZNB-1982-37b-1005 
 Volume    37 
10Author    H. Erbert, W. Roesky, Mathias Noltem, GeorgeM. SheldrickRequires cookie*
 Title    Synthese und Struktur des Trifluoracetyldicyanomethanids Synthesis and Structure of Trifluoroacetyldicyanom ethanide  
 Abstract    A suspension of NaCN in CH3CN was treated with excess of C2F4. The resulting red solution was evaporated to dryness and a red amorphous solid remained. One part of this solid was dissolved in water and a solution of Ph4AsCl was added. During the work-up procedure two salts were isolated, yellow [Ph4A s'][C F 3C (0)C (C N)2~] l a and red [Ph4A s+][(NC)2CC(CN)C(F)NC(CN)2_] 2a. The products were characterized on the basis of field desorption mass spectroscopy for positive and negative ions, l a was further characterized by an X-ray single crystal investigation. 
  Reference    Z. Naturforsch. 40b, 883 (1985); eingegangen am 7. März 1985 
  Published    1985 
  Keywords    X-Ray, Carbanion, Fluorine, Nitrile 
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 TEI-XML for    default:Reihe_B/40/ZNB-1985-40b-0883.pdf 
 Identifier    ZNB-1985-40b-0883 
 Volume    40 
11Author    Gertrud Weiler, Gottfried Huttner, Laszlo Zsolnai, Heinz BerkeRequires cookie*
 Title    Phosphordonor-substituierte Formylmangan-Komplexe Phosphorous Donor Substituted Formyl Manganese Complexes  
 Abstract    Phosphonomanganese complexes (CH 3 0) 2 (0)PMn(C0)3[P(0CH 3)3] 2 (lb), (CH 3 0) 2 (0)PMn(C0) 2 [P(0CH 3) 3 ] 3 (lc) are obtained via demethylation of the corresponding cationic substituted carbonylmanganese compounds with KHB(secBu) 3 . The reaction of NaBH 4 in methanol with cationic phosphorus donor substituted carbonyl manganese compounds leads to formyl complexes (OC) 3 L 2 MnCHO (L = P(OCH 3) 3 (3a), L = P(OEt) 3 (3c), L -P(0*Pr) 3 (3d), L = PPh 3 (3e)) and (OC) 2 [P(OCH 3) 3 ] 3 MnCHO (3b). 3d decomposes thermally to give an (OC) 3 [P(OzPr) 3 ] 2 MnH and an (0C) 2 [P(0/Pr) 3 ] 3 MnH complex. The latter has been characterized by an X-ray structure determination. 
  Reference    Z. Naturforsch. 42b, 203—209 (1987); eingegangen am 22. August 1986 
  Published    1987 
  Keywords    Formyl, Hydride Complexes, X-Ray 
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 TEI-XML for    default:Reihe_B/42/ZNB-1987-42b-0203.pdf 
 Identifier    ZNB-1987-42b-0203 
 Volume    42 
12Author    ManfredL. Ziegler, Klaus Blechschmitt, Harald Bock, Ernst Guggolz, RichardP. KorswagenRequires cookie*
 Title    Über die Reaktivität von [(CH 3 ) 2 N] 6 W 2 (W=W) gegenüber CS 2 /S 8 und CS 2 /Se, Röntgenstrukturanalyse von [(CH 3 ) 2 NCS 2 ] 2 W(S)(S 2 ) Reactivity of [(CH 3 ) 2 N] 6 W 2 (W=W) Towards CS 2 /S 8 and CS 2 /Se 8 . X-Ray Structure Analysis of [(CH 3 ) 2 NCS 2 ] 2 W(S)(S 2 )  
 Abstract    In this paper we report two improved preparation methods for [(CH 3) 2 N] 6 W 2 (W=W) (1), one starting from WC1 4 (yield 51%), and a second one starting from W 2 C1 6 (THF) 4 (ca. 60% yield). We have studied the reactions of 1 with different nucleophiles, among them triphenylalkylidenphos-phoranes (like Ph 3 P=CH 2 and Ph 3 P=CHPh • LiCl; Ph = phenyl), sulfur and CS 2 . 1 reacts with S 8 and CS 2 in hexane to yield the two new compounds (Me 2 NCS 2) 2 WS(S 2) (4) and W(CS 2 H)(Me 2 NCS 2) 2 (5), both containing dithiocarbamato ligands formed by insertion of CS 2 into the W-N bond. The two mononuclear compounds were characterized spectroscopically, in the case of 4 an X-ray diffraction structure analysis was performed. The reaction of 1 with Se and CS 2 , leads to the compounds 4, (Me 2 NCS 2) 2 W 2 S 4 (6) and [(Me 2 N) 2 C]CS 2 (7), which were also characterized spectroscopically. No Se-containing compounds could be isolated. 4 crystallizes monoclinically, C 5 2h -P2Jn, with a = 648.6(3), b = 1346.7(6) and c = 1745.9(7) pm, ß = 91.85(3)°, V = 1524xl0 6 pm 3 , Z = 4. The structure of the seven-coordinate tungsten compound is discussed and compared to complexes with similar ligands and geometry. 
  Reference    Z. Naturforsch. 43b, 590—598 (1988); eingegangen am 28. Dezember 1987 
  Published    1988 
  Keywords    Reactivity, Synthesis, X-Ray 
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 TEI-XML for    default:Reihe_B/43/ZNB-1988-43b-0590.pdf 
 Identifier    ZNB-1988-43b-0590 
 Volume    43 
13Author    HerbertW. Roesky, Ulrich Seseke, Mathias Noltemeyer, GeorgeM. SheldrickRequires cookie*
 Title    Darstellungen und Strukturen viergliedriger Metall-Stickstoff-Ringe Preparations and Structures of Four-Membered Metal-Nitrogen Rings  
 Abstract    Ph 3 P=NSiMe 3 (1) reacts with InCl 3 , SnCl, and FeCl, to yield (Ph,P=N) 2 (InCl 2) 2 • 2 DMF (2a), (Ph 3 P=N) 2 Sn 2 Cl 4 • 2 CH 3 CN (3a) and (Ph 3 P=N) 2 (FeCl 2) 2 (4). The X-ray single crystal structures of 2a, 3a and 4 are reported. The compounds form four-membered rings consisting of alternating metal and nitrogen atoms. 2a and 4 are symmetrical, but 3a has both a Sn(II)Cl and a Sn(IV)Cl 3 group in the four-membered ring. 
  Reference    Z. Naturforsch. 43b, 1130—1136 (1988); eingegangen am 29. März 1988 
  Published    1988 
  Keywords    Indium, Tin, Iron, X-Ray 
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 TEI-XML for    default:Reihe_B/43/ZNB-1988-43b-1130.pdf 
 Identifier    ZNB-1988-43b-1130 
 Volume    43 
14Author    Z. NaturforschRequires cookie*
 Title    Übergangsmetall-substituierte Diphosphene, XXIV [ 1 ]  
 Abstract    Cheletrope [1 +4]-Cycloaddition von Azodicarbonsäureestern und -amiden an das metallsubstituierte Diphosphen (i75-C5M e5)(CO)2F e -P = P -Mes* (Mes* = 2,4,6-*Bu3C6H 2). Struktur von (i/5-C5M e5)(CO)2F e -P (= P -M e s *)|N (C 0 2E t)N = C (0 E t)Ö | Transition M etal Substituted Diphosphenes, XXIV [1] Cheletropic [1+4] Cycloaddition of Azodicarboxylic Esters and Amides to the Metal Substituted Diphosphene (^5-C5Me5)(CO)2F e -P = P -M e s * (Mes* = 2,4,6/Bu3C6H 2). Structure o f (^5-C5M e5)(CO)2F e -P(= P -M es*)[N (C 0 2Et)N = C (0 E t)0 ]. L othar Weber*, Holger Bastian, Achim Müller [2] und H artm ut Bögge [2] The diphosphenyl complex (>75-C 5M e5XCO)2F e -P = P -M e s * (1) (M es* = 2,4,6rBu3C6H2) 
  Reference    Z. Naturforsch. 47b, 231—2 (1992); eingegangen am 9. Juli/26. September 1991 
  Published    1992 
  Keywords    Diphosphene, Cycloaddition, Azodicarboxylates, X-Ray 
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 TEI-XML for    default:Reihe_B/47/ZNB-1992-47b-0231.pdf 
 Identifier    ZNB-1992-47b-0231 
 Volume    47 
15Author    PeterG. Jones, M. Artina, Näveke Und Arm, BlaschetteRequires cookie*
 Title    Polysulfonylamine, XXXI [1] Kristallstruktur von (1-Trichlormethylthio- 4-dimethylaminopyridinium)dimesylamid bei -9 5 °C Polysulfonylamines, XXXI [1] Crystal Structure o f 1-Trichloromethylthio- 4-dimethylaminopyridinium Dimesylamide at -9 5 °C  
 Abstract    The crystal structure o f the title com pound was determined at -9 5 °C. It crystallizes in space group P 1 with a = 577.5(3), b = 820.2(3), c = 1916.6(8) pm, a = 83.34(2), ß = 82.83(2), y = 83.61(2)° and Z = 2. The final R value was 0.034 for 3019 unique observed reflections. The presence o f aggregates o f four ions (two cations and two an­ ions) in the solid state is observed, with short cat-ion-anion contacts Sn — 0 (290 pm) and Cl --O (298 pm). The bond lengths o f the 4-dimethyl-aminopyridinium moiety o f the cation suggest a semiquinoid resonance form with a double bond to the nitrogen o f the dim ethylam ino group and two localized double bonds in the ring. The ring, the dimethylamino group (except H atom s) and the Sn atom are coplanar. The S " -N bond length is 170.3 pm, the N -S " -C angle 99.6°. The S ° -C bond is approximately perpendicular to the ring plane. 
  Reference    Z. Naturforsch. 47b, 441—4 (1992); eingegangen am 17. September 1991 
  Published    1992 
  Keywords    Pyridinium, Dimesylamide, Polysulfonylamine, X-Ray 
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 TEI-XML for    default:Reihe_B/47/ZNB-1992-47b-0441_n.pdf 
 Identifier    ZNB-1992-47b-0441_n 
 Volume    47 
16Author    M. Ustafa Ate, HansJoachim Breunig, KlausH. Ebert, Rose Kaller, M. Artin Dräger, Ulrich BehrensRequires cookie*
 Title    Strukturen von Tetramesityldistiban (Mes4Sb2) und Trimesitylstiban (M es3Sb) Structures of Tetramesityldistibane (Mes4Sb2) and Trimesitylstibane (Mes3Sb)  
 Abstract    The crystal structure of tetramesityldistibane consists of isolated Mes4Sb2 molecules in the trans conformation (average distance S b -C 219 pm, distance S b -S b 284.9(1) pm, angles SbC2 9 7 °-100°, Sb2C 92°-109°). In the structure o f trimesitylstibane there are stacks of isolated tri­ gonal pyramidal Mes,Sb molecules (average distance S b -C 218 pm, angles SbC-, 104 -106°). 
  Reference    Z. Naturforsch. 47b, 503—508 (1992); eingegangen am 18. O ktober 1991 
  Published    1992 
  Keywords    Tetramesityldistibane, Trimesitylstibane, X-Ray 
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 TEI-XML for    default:Reihe_B/47/ZNB-1992-47b-0503.pdf 
 Identifier    ZNB-1992-47b-0503 
 Volume    47 
17Author    K. Urt Merzweiler, Ludwig Brands, Jürgen SpohnRequires cookie*
 Title    Neue In2P2-Vierringe  
 Abstract    Synthese und Kristallstrukturen von [{iPrIn(//-fBu2P)Cl}2] und [{Me3SiCH2In(/i-fBu2P)Cl}2l New Four-M em bered In2P2 Rings. Snythesis and Crystal Structures of [{/PrIn(//-/Bu2P)Cl}2] and [~{Me3SiCH2In(//-/Bu2P)Cl}2] The reaction of organoindium halides R InC l2 with /Bu2PSiMe3 leads to compounds of the type [{RIn(jU-rBu2P)Cl}2] (R = /P r : 1, M e3SiCH2: 2). According to the crystal structure deter­ minations 1 and 2 contain planar In7P, rings. The In atoms are coordinated to two bridging /Bu,P groups, a terminal alkyl group and a term inal 
  Reference    Z. Naturforsch. 48b, 1315—1320 (1993); eingegangen am 29. M ärz 1993 
  Published    1993 
  Keywords    Indium, Phosphorus, X-Ray 
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 TEI-XML for    default:Reihe_B/48/ZNB-1993-48b-1315.pdf 
 Identifier    ZNB-1993-48b-1315 
 Volume    48 
18Author    M. Arkus Brylak, Wolfgang JeitschkoRequires cookie*
 Title    U3TiSb5, U3VSb5, U3CrSb5, and U3MnSb5 with "Anti"-Hf5Sn3Cu Type Structure  
 Abstract    The title compounds have been prepared from the elem ental com ponents by arc-melting and subsequent annealing. Single crystals of U 3TiSb5 and U 3M nSb5 were obtained from a tin flux and their structures were determined from single-crystal X-ray data: P 63/mcm, Z = 2; a = 913.9(2), c = 611.2(1) pm, R = 0.011 (233 structure factors, 14 variables) for U 3TiSb5 and a = 916.8(2), c = 613.2(1) pm, R = 0.015 (427 structure factors, 14 variables) for U 3MnSb5. The lattice constants of the isotypic compounds are: a -908.2(2), c = 608.3(2) pm for U 3VSb5 and a -911.0(1), c = 611.5(1) pm for U^CrSb^. The structure of these antimonides may be regarded as an "anti"-type structure of Hf5Sn3Cu with the antimony atoms on the hafnium sites, while the positions of the uranium and transition metal atoms correspond to the posi­ tions of the tin and copper atoms. A comparison o f the interatomic distances of UVTiSbs with those of U 3Sb4, USb2, and a-antimony suggests oxidation numbers according to (U +III)3Ti+,v(S b l_III)3(S b 2_,I)2, where the Sb2 atoms form weakly bonded chains. 
  Reference    Z. Naturforsch. 49b, 747—752 (1994); received D ecem ber 16 1993 
  Published    1994 
  Keywords    Lattice Constants, Antimonides, X-Ray 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0747.pdf 
 Identifier    ZNB-1994-49b-0747 
 Volume    49 
19Author    Norbert Kuhn3, Riad Fawzi3, M. Anfred Steimann3, Jörg Wiethoff3, D. Ieter Bläserb, Roland BoesebRequires cookie*
 Title    Synthese und Struktur von 2-Imino-l,3-dimethylimidazolin [1] Synthesis and Structure of 2-Imino-l,3-dimethylimidazoline [1]  
 Abstract    Deprotonation of the 2-amino-1,3-dimethylimidazolium salt 5 (obtained through methyla-tion of 2-am ino-l-m ethylim idazole (4)) by KH gives 2-im ino-l,3-dim ethylim idazoline 6. The trimethylsilylimino compound 14 is formed on the reaction of 6 with chlorotrimethylsilane in the ratio 2:1. Further reaction with chlorotrimethylsilane gives the silylated aminoimidazo-lium salt 15. The X-ray structures o f 5 and 6 are reported. 
  Reference    Z. Naturforsch. 50b, 1779—1784 (1995); eingegangen am 23. Mai 1995 
  Published    1995 
  Keywords    Imidazole, Imine, X-Ray 
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 TEI-XML for    default:Reihe_B/50/ZNB-1995-50b-1779.pdf 
 Identifier    ZNB-1995-50b-1779 
 Volume    50 
20Author    Norbert Kuhna, Hans Bohnena, Gerald Henkelb, Jörg KreutzbergbRequires cookie*
 Title    5-Tetramethyl-2-methylenimidazoline -an Olefin with Ylidic Properties [ 1]  
 Abstract    A facile synthesis of l,3,4,5-tetramethyl-2-methylenimidazoline 5 (Im) starting from the pentamethylimidazolium ion (8) and KH is described. Boranes react with 5 to give the adducts ImBHi (11) and ImBF3 (18). With Mel and CH3C(0)C1 the imidazolium salts ImMe+ (19) and Im C (0)M e+ (20) are obtained. CS2 gives the zwitterionic compound ImCS2 (24) which is transformed into the cationic thiocarboxylic ester ImC(S)SCH2Cl+ on treatment with CH2C12. Reaction with chlorotrimethylsilane gives the imidazolium ion ImSiMe^ (26) which may be transferred into the disilylated imidazolium ion 28 via deprotonation and subsequent silylation, the silylated olefin 27 being the intermediate. Similarly, the cations ImSiR2Cl+ (29; R = Me, Ph) are obtained from 5 and the silanes R2SiCl2. The neutral adduct ImSnPh2Cl2 (32) is formed in the reaction of 5 with Ph2SnCl2. Iodine reacts with 5 to give the charge-transfer adduct Im l2 (35), which can be further transferred into the imidazolium salt Im l+I^ (36). verhilft Imidazolin-Derivaten des Typs 1 durch die Dominanz der Grenzstruktur 2 zu einer Ylid-artigen Bindungssituation. Als Belege können die Eigen­ schaften der 2-Chalkogenoimidazoline 1 (X = S [3,41, Se [4 -6 ], Te [4,7]) sowie des 2-Iminoimi-dazolins 3 (1 ,8 ] gelten. Die bekannte Polarisierung der olefinischen Dop­ pelbindung durch Substituenten mit +M-Charak-ter ist im Falle der Enamine [9] gut untersucht; durch Einbindung der Stickstoff-Atome des 1,1-Endiamins 4 in ein fünfgliedriges Ringsystem wird eine bemerkenswert hohe Basizität des Methylen­ kohlenstoffs erreicht [10]. Hierzu analog läßt sich durch Einbau eines olefinischen Kohlenstoffs in ein System zyklisch konjugierter 7 r-Elektronen gleich­ falls eine starke Polarisierung der olefinischen Dop­ pelbindung erreichen [11]. Die Kombination beider Effekte führt zum System des 2-Methylenimidaz-olins. Synthese und strukturelle Charakterisierung des Tetramethyl-Derivats 5 sind Gegenstand einer vorläufigen Mitteilung [12]. Über die Kupplungsre­ aktion von 5 zum Methinium-Kation 6 [13] sowie seine koordinationschemische Fixierung an Metall­ zentren (7) [14, 15] haben wir bereits an anderer Stelle berichtet. 
  Reference    Z. Naturforsch. 51b, 1267—1278 (1996); eingegangen am 8. März 1996 
  Published    1996 
  Keywords    Imidazoles, Olefins, X-Ray 
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 TEI-XML for    default:Reihe_B/51/ZNB-1996-51b-1267.pdf 
 Identifier    ZNB-1996-51b-1267 
 Volume    51