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1994[X]
1Author    Crystal Structure, Sbcl4fR. Olf, M. Inkwitz, D. Etlef, K. Onikow Ski, H. Ans PreuRequires cookie*
 Title    Kristallstruktur von SbCl4F  
 Abstract    The crystal structure of SbCl4F is reported. SbCl4F crystallizes in the tetragonal space group 14 with a = 1278.4(6), c = 774.1(5) pm, V = 1265(1) • 106 pm3 and Z = 8. Four SbCl4F units are linked via symmetric Sb-F-contacts forming an eight-membered heterocycles. 
  Reference    (Z. Naturforsch. 49b, 1—4 [1994]; eingegangen am 25. September 1993 Preparation Crystal Structure) 
  Published    1994 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0001.pdf 
 Identifier    ZNB-1994-49b-0001 
 Volume    49 
2Author    Lib, P. Eter, H., R. Üdiger, K. Niep, JoachimM. AierRequires cookie*
 Title    LiBa4[Mo2N7] und LiBa4[W2N7]: Neue Nitridomolybdate/wolframate(YI) mit dinieren Tetraeder-Anionen  
 Abstract    a4[M o2N 7] and LiB a4[W 2N 7]: New N itrid o m olybdates/tungstates(V I) w ith D im eric T etrahedral A nions Black crystals of the isotypic phases LiBa4[Mo2N7] and LiBa4[W2N7] (monoclinic, P2/n; a = 1552.2(3)/1555.2(4), b = 642.2(1)/644.4(1), c = 1039.9(2)/1042.4(2) pm; ß = 99.23(2)/99.30(3)°; Z = 4) were grown from the melt (Li, Ba3N2, MoAV; molar ratio 20:5:1; = 1323 K; re­ action with N2, 1 atm, 18 h) by cooling (20 K7h). The crystal structures contain two indepen­ dent dimeric units [ M O j N ^ / ^ N ,] 9-(staggered conformation; M o/W -N -M o/W : 173.6/173.7° and 180°/180°; " M o/W -N (term): 180(2)-185(1)/181(3)-185(1) pm; M o/W -N (bridg): 195(1)7194(1) pm and 193(1)/194(1) pm). 
  Reference    (Z. Naturforsch. 49b, 5—8 [1994]) 
  Published    1994 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0005.pdf 
 Identifier    ZNB-1994-49b-0005 
 Volume    49 
3Author    H. Einrich, N. Öth, M. Artina, T. Hom AnnRequires cookie*
 Title    Metal Tetrahydroborates and Tetrahydroboratometalates, 18 [1] Studies on the Formation of Cadmium(II)-tetrahydroborates with Tetrahydroborate and Iodide  
 Abstract    The structure of cadmium tetrahydroborate in THF solution is fluxional on the NMR time scale and best described as Cd[(a-H)2BH2]2-rcTHF as indicated by IR data. Reactions of LiBH4 with Cd(BH4)2 in THF yield the monoanion [Cd(BH4)3]_ exclusively, while a dilithium salt Li2[Cd(BH4)4] • 4 diglyme precipitates from diglyme solutions. Equilibria involving ICd(BH4), Cdl2, Cdl3~, [Cd(BH4)3]-and/or [ICd(BH4)2]~ result from Cd(BH4)2 and Lil in THF or diglyme. The solvent as well as the cation of the iodide (Cd2+ or Li+) influence the equilibria. This can be explained in terms of the different polarity and chelating ability of the solvents. 
  Reference    (Z. Naturforsch. 49b, 9—1 [1994]; received August 30 1993) 
  Published    1994 
  Keywords    Cadmium Bis(tetrahydroborate), Tris(tetrahydroborato)cadmate, Tetrakis(tetrahydroborato)cadmate, Iodo Tetrahydroborato Cadmates, nB NMR Spectra, U3Cd NMR Spectra 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0009.pdf 
 Identifier    ZNB-1994-49b-0009 
 Volume    49 
4Author    Z. NaturforschRequires cookie*
 Title    Die isoelektronischen Molekülkomplexe TiCl3(NPPh3) und TiCl3(OSiPh3)  
 Abstract    The Isoelectronic M olecular C om plexes TiC l3(N P P h 3) and T iC l3(O SiPh3) Thilo R übenstahl, D o ro th ea W olff von G udenberg, F ra n k W eller, K u rt D ehnicke* TiCl3(NPPh3) and TiCl3(OSiPh3) have been prepared from titanium tetrachloride and Me3SiNPPh3 and HOSiPh3, respectively. Both complexes were characterized by IR spectrosco­ py and by crystal structure determmations. TiCl3(N PPhj): Space group R3, Z = 6, structure analysis with 959 observed unique reflec­ tions, R = 0.039. Lattice dimensions at -6 8 °C: a = b = 1370.5(7), c = 1845.9(9) pm. TiCl}(OSiPh3): Space group P2,/c, Z = 8, structure analysis with 4549 observed unique re­ flections, R = 0.049. Lattice dimensions at 19 °C: a = 2127.7(2), b = 947.2(1), c = 2136.8(1) pm, ß = 105.081(5)°. Both complexes form monomeric molecules in which the titanium atom is tetrahedrally coordinated by three chlorine atoms, the nitrogen atom of the phosphorone iminato ligand and the oxygen atom of the silyloxy group, respectively. The bond lengths TiN of 171.9(4) pm and TiO of 171.0(3) (in average) correspond to double bonds. 
  Reference    (Z. Naturforsch. 49b, 15—20 [1994]; eingegangen am 7. September 1993) 
  Published    1994 
  Keywords    Monomerie Titanium Complexes, Synthesis, Crystal Structure 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0015.pdf 
 Identifier    ZNB-1994-49b-0015 
 Volume    49 
5Author    W. Olfgang Eikens, P. Eter, G. Jones, Jü Rg, L. Au Tn Er, C. Arsten, ThöneRequires cookie*
 Title    Complexes of Copper, Silver, and Gold with Urea Homologues. Crystal Structures of I{/i2-SeC(NH2)2} Ag{SeC(NH2)2}2]22+2 Cl~ * 4 DMF and [Ph3PAu{SC(NHMe)2}]+Cl" * SC(NHMe)2  
 Abstract    The title compounds were prepared from chloro(organophosphine)metal(I) complexes and the urea homologues SeC(NH2)2 and SC(NHMe)2 in good yields. Recrystallization of [Ph,PAg{SeC(NH2)2}]+C r from D M F/C H 2C12 leads in low yield to the dinuclear complex [{/r-SeC(NH2)2}Ag{SeC(NH2)2}2]22+2 C r-4 D M F . The crystal structure reveals short A g-A g contacts and unexpectedly acute angles at the bridging selenium atom. The crystal structure of [Ph3PAu{SC(NHMe)2}]+Cl_ • SC(NHMe)2 shows short N --C1 and N -S con­ tacts that probably correspond to hydrogen bonding. 
  Reference    (Z. Naturforsch. 49b, 21—26 [1994]; received August 12 1993) 
  Published    1994 
  Keywords    Coinage Metal Complexes, X-Ray, Urea Homologues 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0021.pdf 
 Identifier    ZNB-1994-49b-0021 
 Volume    49 
6Author    Z. NaturforschRequires cookie*
 Title    Gold-Alkalimetallsysteme, III. Hochdrucksynthese und Kristallstruktur von Rb3Au7 [1]  
 Abstract    G old-A lkali M etal-System s, III. H igh Pressure Synthesis and C rystal S tructure o f R b 3A u 7 [1] K laus-Jürgen Range*, G eorg H. G rosch, F ran z R au, U lrich K lem ent The intermetallic compound Rb3Au7 could be synthesized from the elements at 4 kbar, 700 °C in a modified Belt-type apparatus. The structure (Cmmm; a = 5.579(1), b = 13.267(5), c = 7.265(2) Ä; Z = 2; R = 0.035, Rw = 0,031) comprises three crystallographically independ­ ent Au atoms, arranged in layers along the c-axis. The shortest interatomic distances are A u -A u = 2.633Ä, A u -R b = 3.438Ä and R b -R b = 3.622Ä. Im System R ubidium -G old [2,3] sind bisher n u r die V erbindungen R b A u [4] und R b A u 5 [5,6] ein­ deutig nachgewiesen und strukturell c h a ra k te ri­ siert w orden. Die Existenz von R b A u 2 [2,3,7] ko n n te bisher nicht verifiziert werden. D ie h o m o ­ logen V erbindungen N aA u 2 [8] und K A u 2 [9] sind Lavesphasen und kristallisieren im kubischen M gC u2-Typ bzw. im hexagonalen M g Z n 2-Typ. Bei unseren V ersuchen zur H ochdrucksynthese einer L avesphase R b A u 2 fanden wir nun eine bisher im System R b -A u unbekannte Phase d er Z u sam ­ m ensetzung R b 3A u 7, über die im folgenden berich­ tet w ird. 
  Reference    (Z. Naturforsch. 49b, 27—30 [1994]; eingegangen am 6. Juli 1993) 
  Published    1994 
  Keywords    Trirubidium Heptagold, High Pressure Synthesis, Crystal Structure 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0027.pdf 
 Identifier    ZNB-1994-49b-0027 
 Volume    49 
7Author    Z. NaturforschRequires cookie*
 Title    Reactions of Bis(hexamethyldisilazanyl)manganese(II) with Nitrogen Containing Ligands: Syntheses and X-Ray Structures of [Mn( 1,10-phen){N(SiMe3)2}2] and |Mn(4,4 -bipy){N(SiMe3)2}2] THF  
 Abstract    , 1993 Manganese Amides, X-Ray The reaction of [Mn{N(SiMe3)2}2 (THF)] 1 with 2,2'-bipyridine (2,2'-bipy), 1,10-phenan-throline (1,10-phen) and 4,4'-bipyridine (4,4'-bipy) yields three new complexes: [Mn(2,2'-bipy){N(SiMe3)2}2] 2, [Mn(l,10-phen){N(SiMe3)2}2] 3, and [Mn(4,4'-bipy){N(SiMe3)2}2] ■ THF 4. The crystal structure of 3 reveals mononuclear species with pseudo-tetrahedral coordinated manganese(II) ions. Crystal data for 3: orthorhombic, a = 1741.0(2), b = 1879.3(3), c = 1967.0(3) pm, V = 6.436(2) nm3, Z = 8, space group Pbca. Compound 4 crystallizes in the monoclinic system, space group P 2{/c; the lattice parameters are: a = 2139.5(3), b = 925.30(10), c = 1786.4(2) pm, ß = 101.34(1)°, V= 3.4675(7) nm3, Z = 4. The molecular structure of 4 consists of zig-zag infinite chains, with bridging 4,4'-bipyridine groups. 
  Reference    (Z. Naturforsch. 49b, 31—3 [1994]; received August 9) 
  Published    1994 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0031.pdf 
 Identifier    ZNB-1994-49b-0031 
 Volume    49 
8Author    JonesRequires cookie*
 Title    Polysulfonylamine  
 Abstract    , LIV [1] (12-Krone-4)lithiumdimesylamid-Acetonitril (3/2): Ein Kristall mit zwei prinzipiell unterschiedlichen Konformationen des gleichen Coronanden Polysulfonylam ines, L IV [1] (12-Crow n-4)lithium D im esylam ide-A cetonitrile (3/2): A Crystal w ith Two F undam entally D ifferent C onform ations of the Sam e C oronand A rm an d Blaschette*, K arl-H einz N agel, P e te r G. [Li(12-crown-4){N(S02CH3)2}] is obtained from equimolar amounts of lithium dimesyl­ amide and 12-crown-4 in methanol and crystallizes from acetonitrile as a 3/2 solvate. The crystallographic data of the latter at -130 °C are: monoclinic, space group P 2In, a = 1053.4(3), b = 904.3(3), c = 2791.2(8) pm, ß = 95.66(3)°, V = 2.646 nm3, Z = 6, Dx = 1.441 Mgm~3. Apart from CH3CN molecules residing in lattice cavities, the structure consists of two crystallogra-phically independent [Li(12-crown-4){N(S02CH3)2}] ion pairs A and B in the ratio 2:1. In B, the Li and N atoms lie on a crystallographic twofold axis. In both ion pairs, Li is hexa-coordinated by the four crown oxygen atoms O(C) and by one oxygen O(S) from each sul-fonyl group of the anionic ligand. The coordination geometry of Li in A closely resembles that of Cu11 in the known structure of [Cu(12-crown-4)Cl2] and can be pictured as a distorted octahedron, where two cis sites are occupied by the O(S) atoms and the remaining vertices by the four oxygens of the macrocycle, which displays a [4 8] conformation. The lithium atom, the two O(S) and two O(C) atoms are arranged in an approximately square-planar pattern with L i-O (S) 203.6 and 205.1, L i-O (C) 206.9 and 219.1 pm, trans angles of 173.7 and 174.8°, and cis angles in the range 87.1 -93.6°. The angle between the remaining two Li -O(C) bonds with distances 214.7 and 221.5 pm is only 146.5° compared with 180° in an ideal octahedron. In ion pair B, the coronand assumes a [3 3 3 3] conformation close to C4 symmetry, as observ­ ed e. g. in the known structures of [Li(12-crown-4)NCS] with a square-pyramidal 0 4N-co-ordination and [Ca(12-crown-4)(H20) 4]Cl2-4 H zO with a square-antiprismatic 0 8-geometry. The coordination polyhedron in B can be viewed as an incomplete cube in which two verti­ ces related by a face diagonal are unoccupied. Important bond lengths and angles in B are: L i-O (S) 216.8, L i-O (C) 214.0 and 228.7pm; 0 (S) -L i-0 (S) 82.0, 0 (C) -L i-0 (C) 75.7/76.3 for adjacent and 120.4/121.9° for opposite ring oxygens. 
  Reference    (Z. Naturforsch. 49b, 36—42 [1994]; eingegangen am 2. September 1993) 
  Published    1994 
  Keywords    Polysulfonylamines, (12-Crown-4)lithium Dimesylamide, Synthesis, Crystal Structure, Coronand Conformation 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0036.pdf 
 Identifier    ZNB-1994-49b-0036 
 Volume    49 
9Author    G. Stalke, M. Eorge, SheldrickRequires cookie*
 Title    Neue Cyclophosphazene mit Metallen der III. Hauptgruppe als Ringbausteine  
 Abstract    Acylic silylated phosphazenes of the type HN(PR2NSiMe3)2 (1) react quantitatively with molecules MMe3 (M = Al, Ga, In) under ring formation and CH4 evolution. The ring com­ pounds N(PPh2NSiMe3)2AlMe2 (2 a) and N(PPh2NSiMe3)2InMe2 (4 a) have been investiga­ ted by X-ray structure determination. 2a and 4a crystallize in the space groups P 1 and P 3 15 respectively; they show different conformations regarding the cyclohexane framework. NMR spectroscopy of the nuclei in the chelating phosphazene ligand indicates decreasing Lewis acidity of the metal containing fragments in the series AlMe2 > GaMe2 > InMe2. 
  Reference    (Z. Naturforsch. 49b, 43—49 [1994]; eingegangen am 22. September 1993) 
  Published    1994 
  Keywords    Cyclophosphazenes, Chelating Ligands, Conformational Isomers, Lewis Acidity, 27Al NMR Spectra 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0043.pdf 
 Identifier    ZNB-1994-49b-0043 
 Volume    49 
10Author    Z. NaturforschRequires cookie*
 Title    Darstellung, Eigenschaften und elektronische Raman-Spektren von Di(bromo)phthalocyaninatometallaten(III) der Eisengruppe  
 Abstract    Synthesis, P ro p erties an d E lectronic R am an Spectra of D i(b ro m o)p h th alo cy an in ato m etalates(III) of the Iron G roup E lem ents Svend Sievertsen, H en d rik Schlehahn, H ein er H om borg Low spin di(bromo)phthalocyaninatometalates of tervalent iron, ruthenium and osmium ([MBr2Pc2-]') are formed by the reaction of [FeBrPc2~] or H[MBr2Pc2 ] (M = Ru, Os) with ex­ cess bromide in DMF or THF and isolated as ("Bu4N)+ salts. The electronic spectra show the typical J i-jr*-transitions (B, Q, N region) of the Pc2~ ligand together with a number of extra bands due to trip-multiplett and (Pc, Br — » M)CT transitions. vs(MBr) is observed in the resonance Raman (RR) spectrum (RR enhanced for M = Fe, Ru) at 161 cm-1 (Fe), 183 cm4 (Ru) and 192 cm-1 (Os), vas(MBr) at 251 cm4 (Fe), 234 cm-1 (Ru) and 218 cm-1 (Os) in the FIR spectra. The RR spectra obtained by excitation at low absorbance between the B and Q region are dominated by the intraconfigurational 'T 7 — > r 8" transition due to spin orbit split­ ting of the 2T2g ground state for Fe at 583 cm-1, Ru at 1026/1050 cm-1 and Os at 3131 cm4 . In the MIR resp. NIR spectra vibronically induced transitions are observed for the Ru or Os complex. 
  Reference    (Z. Naturforsch. 49b, 50—56 [1994]; eingegangen am 31. August 1993) 
  Published    1994 
  Keywords    Phthalocyanines, Electronic Spectra, Vibrational Spectra, Electronic Resonance Raman Spectra 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0050.pdf 
 Identifier    ZNB-1994-49b-0050 
 Volume    49 
11Author    W. S. Sheldrick, B. SchaafRequires cookie*
 Title    Cs2SnTe4, ein Polytelluridostannat(rV) mit Kettenstruktur ^[SnTeJ-] Cs2SnTe4, a Polytelluridostannate(IV ) w ith Chain S tructure ^[SnTef-]  
 Abstract    Polytelluridostannate(IV), Methanolothermal Synthesis, Crystal Structure The cesium polytelluridostannate(IV) Cs2SnTe4 has been prepared by methanolothermal reaction of Cs2CÖ3 with Sn and Te at 190 °C. The crystal structure contains chain anions i[SnTe|~]oin which individual SnTe4 tetrahedra are linked via T e -T e bonds of length 2.814(3) Ä. Weak Te —Te secondary bonds of length 3.631(3)-3.663(3) Ä connect neigh­ bouring chains into a framework structure. Nine Te atoms from three chain anions partici­ pate in the coordination sphere of the cesium cation. 
  Reference    (Z. Naturforsch. 49b, 57—59 [1994]; eingegangen am 13. September 1993) 
  Published    1994 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0057.pdf 
 Identifier    ZNB-1994-49b-0057 
 Volume    49 
12Author    Hans-Ulrich Hummel, Petra Joerg, Gerhard Pezzei, Alexander WolskiRequires cookie*
 Title    Die Kristallstruktur von Gadolinium (III)-sulfit Trihydrat Gd2(S 0 3)3*3H20 Crystal Structure of Gadolinium(III)-sulfite Trihydrate Gd2(S 0 3)3-3 HzO  
 Abstract    Gadolinium(III)-sulfite, Preparation, Crystal Structure Gd2(S03)3 • 3 H20 is obtained by passing gaseous S 0 2 through a suspension of Gd20 3 in H20 at room temperature until a clear solution is formed. Single crystals are obtained by heating to 70(2) °C for 6 days. The compound crystallizes in the triclinic space group P 1 with a = 6.499(6), b = 6.621(3), c = 6.954(3) Ä, a = 110.71(5), ß = 90.54(3), y = 106.05(1)° and Z = 1. The two crystallographically different gadolinium atoms are both coordinated by eight oxygen atoms forming distorted square antiprisms. Gd(l) is coordinated by six O atoms of sulfite ligands and two O atoms of water, while Gd(2) is surrounded by seven O atoms of S 0 3 and one of HzO. Gd-O-bond lengths vary between 2.31(3) and 2.50(3) Ä. 
  Reference    (Z. Naturforsch. 49b, 60—62 [1994]; eingegangen am 9. Juli/23. September 1993) 
  Published    1994 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0060.pdf 
 Identifier    ZNB-1994-49b-0060 
 Volume    49 
13Author    Gerhard Himbert, Dieter Fink, Martina Stürm, Herrn Prof, O J Dr, SchererRequires cookie*
 Title    Cycloadditionen, XXI [1]. 2-Methyl-2,3-butadiensäure-arylester; Synthese und thermische Reaktivität Cycloadditions, XXI [1] Aryl 2-methyl-2,3-butadienoates; Synthesis and Thermal Reactivity  
 Abstract    Aryl 2-Methyl-2,3-butadienoates, Intramolecular Diels-Alder Reaction The substituted phenyl, 1-naphthyl or the 9-anthrylmethyl esters of the 2-methyl-(or 2-phenyl)-2,3-alkadienoic acids (see 4 a -g , 9 a -d and 12a,b) are synthesized by condensation of the allenic acids 2 a -d with the substituted phenols 3 a -g , with 1-naphthol (8) or with 9-anthrylmethanol (11) in the presence of dicyclohexyl carbodiimide (DCC) and a catalytic amount of 4-dimethylaminopyridine (DMAP). An alternative route is the reaction of the acid chloride la with the phenols 3 a -c (see formation of 4 a -c) in the presence of triethylamine. All these compounds (except 12a) undergo the intramolecular Diels-Alder (IMDA)-reaction to form the tricycles 6 a -g , lO a-d and 13. The enol ether 6a is hydrolized during chromato­ graphy to give the tricyclic ketone 7. The influence of the geminal methyl group on the rate of the IMDA-reaction is investigated. 9-Anthryl-and (2,4,6-cycloheptatrien-l-on-2-yl)-2-methyl-2,3-butadienoate (15, 17), formed by reaction of 2-methyl-2,3-butadienoyl chloride (la) with 9-anthrone (14) and 2-tropolone (16) isomerise spontaneously to the IMDA-products 19 and 18. 
  Reference    (Z. Naturforsch. 49b, 63—75 [1994]; eingegangen am 2. August 1993) 
  Published    1994 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0063.pdf 
 Identifier    ZNB-1994-49b-0063 
 Volume    49 
14Author    Dieter Sellmann+, Helge Friedrich, Falk Knoch, Matthias MollRequires cookie*
 Title    Übergangsmetallkomplexe mit Schwefelliganden, C*. Unerwartet einfache Bildung von Diazen-Komplexen und ein neuer Typ von Diastereomerie: [/#-N2H2{Fe(PPr3)('S4')}2] und analoge Komplexe mit [FeS]-Zentren. ( 'S /2-= l,2-Bis(2-mercaptophenylthio)ethan(2-)) Transition Metal Complexes with Sulfur Ligands, C*. Unexpectedly Facile Formation of Diazene Complexes and a New Type of Diastereomerism: [a-N2H2{Fe(PPr3)('S4')}2] and Analogous Complexes with [FeS]-Centers. ('S4'2~ = l,2-Bis(2-mercaptophenylthio)ethane(2-))  
 Abstract    Single pot reactions of FeCl2-4H20 with the tetradentate thioether-thiol 'S4-H 2' = 1,2-bis(2-mercaptophenylthio)ethane, phosphines such as PEt3, PPr3 or PBu3, and a ca. 40-fold excess of N2H4-H20 yield, in the presence of air, diazene complexes of the general formula [M-N2H2{Fe(PR3)('S4')}2]. In contrast to previous syntheses of diazene complexes, the yields can excel 80%, and the syntheses can be carried out on a 10 g scale. [M-N2H2{Fe(PPr3)('S4')}2], 1 and [M-N2H2{Fe(PEt3)('buS4')}2], 2 were characterized by X-ray structure analysis. 2 contains 'buS4'2-= l,2-bis(3,5-ditertiarybutyl-2-mercaptophenylthio)-ethane(2-), which is the tertiary-butyl derivative of 'S4'2-. 1 and 2 contain fram-HN=NH which bridges enantiomeric [Fe(PPr3)('S4')] or [Fe(PEt3)('buS4')] fragments. HN=NH is stabilized by 4c -6 e~-jr bonds, strong tricentric N -H — (S)2 bridges, and steric shielding. NMR studies show that centrosymmetric 1 isomerizes in solution at temperatures around 0 °C in order to give a diastereomerie diazene complex which is also centrosymmetric. The diastereomerism is traced back to bridging the chiral [Fe(PPr3)('S4')] fragments by frara-HN=NH in a differ­ ent way. The two different bridging modes are verified by X-ray structure analyses of analo­ gous ruthenium complexes. Because this new type of diastereomerism is basically caused by a different position only of the N -H — (S)2 bridges, it is termed hydrogen bridge diastereo­ merism. A mechanism for the isomerization is suggested. 1 exhibits three anodic waves in the cyclovoltammogram. The second wave indicates formation of the dication [1]2+, which is a redox isomer of the diprotonated (and as yet hypothetical) dinitrogen complex [a-N2{Fe(PPr3)('S4')}2]. The significance of [1]2+ and of its Lewis basic thiolate donors with respect to electrochemical reduction of molecular dinitrogen under mild conditions is dis­ cussed. 
  Reference    (Z. Naturforsch. 49b, 76—88 [1994]; eingegangen am 9. Juli 1993) 
  Published    1994 
  Keywords    Diazene, Iron Sulfur Complexes, Synthesis, X-Ray 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0076.pdf 
 Identifier    ZNB-1994-49b-0076 
 Volume    49 
15Author    Unsymmetrische Diorganomagnesiumverbindungen, Heiko Viebrock, Dirk Abein, Erwin Weiss+Requires cookie*
 Title    Über Metallalkyl-und -arylverbindungen, 51. Mittig.* On Metal Alkyl and Aryl Compounds, Part 51 Unsymmetrical Diorganomagnesium Compounds. MgRR'(L) and Solvens Separated Ion Pairs with R = Me  
 Abstract    Amine adducts of diorganomagnesium compounds MgR2(L) are soluble in hydrocarbons and therefore valuable synthons for reactions in non-polar solvents. In this way unsymmetri-cally substituted derivatives MgRR'(L) become available by substituting one organic group by a different carbanion via acid-base reactions, according to eq. (1): R2Mg(L) + HR' -> RR'Mg(L) + HR (1) with HR' being stronger CH-acids than HR. Using the amin adducts R2Mg(L) (R = Me, Et) with chelating amines (L = tetramethyl­ ethylenediamine, TMED A, pentamethylethylenetriamine, PMDTA) and the strong CH-acids cyclopentadiene, indene, fluorene and alkynes the following compounds have been synthe­ sized and their structures derived by X-ray analyses: MgMe(?/3-cyclopentadienyl)(tmeda) (1), MgMe(?73-indenyl)(tmeda) (2), MgMe(^1-fluorenyl)(tmeda) (3), [Mg2Me2(pmdta)2]2+[fluo-renyl]2-benzene (4) and [Mg2Et(phenylethynyl)3(tmeda)]2-benzene (5). It is remarkable, that cyclopentadienyl, indenyl, and fluorenyl ligands have a lower hapticity than rj5 to the metal, due to steric repulsion by the other ligands. In 4 the bulky tridentate base PMDTA prevents any direct interaction between the fluorenide anion and magnesium, giving solvens separated ion pairs with the unusual and hitherto rare example of an organomagnesium cation [Mg2Me2(pmdt)2]2+. The 1:3 compound 5 has a more complicated structure, related to that of alkali metal alkynyl magnesates. 
  Reference    (Z. Naturforsch. 49b, 89—99 [1994]; eingegangen am 17. August 1993) 
  Published    1994 
  Keywords    Unsymmetrical Diorganomagnesium Compounds, Synthesis, Crystal Structure, Base Adducts, Chelating Di-and Triamines 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0089.pdf 
 Identifier    ZNB-1994-49b-0089 
 Volume    49 
16Author    Hans-Jürgen Plinta, Ion Neda, Reinhard SchmutzlerRequires cookie*
 Title    .3-Dimethyl-l,3-diaza-2-R-5,6-benzo-2 A3-phosphorinan-4-one (R = F, Me2N, 2-Methylpiperidino, MeC(: 0 ) N H -) als Liganden in Übergangsmetallkomplexen; Synthese und Struktur von Dichloro-Platin(II)-und Tetracarbonyl-Metall(O)- Koordinationsverbindungen (Metall = Cr, Mo und W) 1.3-Dimethyl-l,3-diaza-2-R-5,6-benzo-2/l3-phosphorinan-4-ones (R = F, Me2N, 2-Methylpiperidino, MeC(: 0 ) N H -) as Ligands in Transition-Metal Complexes; Synthesis and Structure o f Dichloro-Platinum(II)-and Tetracarbonyl-Metal(O) Coordination Compounds (Metal = Cr, Mo and W)  
 Abstract    -2-fluoro-5,6-benzo-l,3,2-phosphorinane-4-one (1) reacted with (COD)PtCl2 (COD = 1,5-cyclooctadiene) or K2PtCl4 to give the c/s-dichloro-platinum(II) complex (2). The reactions of 1 with the tetracarbonyl norbornadiene derivatives of Cr, Mo and W furnished the complexes 3 -6 . In the case of the chromium and tungsten complexes the trans-isomers 3 and 6 were formed, due to a c/s-?ra«s-isomerization. Room temperature and low temperature 3IP NMR spectra of a mixture of 5 and 6 show no significant temperature dependence of the cis-trans equilibrium. The reaction of 1 with the pentacarbonyl tetrahydro-furan derivative of W led to the product 7. The spirophosphoranes 8 and 9 were obtained in low yields. The analogous reactions of 10, 15 and 20 with (COD)PtCl2 and the tetracarbonyl norbornadiene derivatives of Cr and Mo furnished the coordination compounds 1 1 -1 4 , 16-18, 21 and 23. In the case of all chromium complexes only the /rarcs-isomers 11,16 and 21 were formed, whereas in the case of molybdenum m-fraH.s'-isomer mixtures 12 and 13, as well as 17 and 18 were obtained. An attempt to obtain the cis-isomer of the molybdenum complex 22 failed. In the case of platinum the expected m-complexes 14 and 23 were formed, while the attempted synthesis of 19 was unsuccessful. All these results are interpreted in terms of both steric and electronic factors. The ligands 1, 10, 15 and 20 coordinate via phosphorus. The va­ lidity of the concept of hard and soft acids and bases (HSAB) was confirmed. The characteri­ zation of 2 -7 , 1 1-14, 16-18, 21 and 23 rests, especially, on their 'H, 13C and 3IP NMR spec­ tra, and their mass and infrared spectra. 31p -3,p coupling constants 2/(PP) for the cis-coordi­ nated complexes 4, 5 and 14 involving two equivalent phosphorus ligands are also reported. 
  Reference    (Z. Naturforsch. 49b, 100—110 [1994]; eingegangen am 17. Mai 1993) 
  Published    1994 
  Keywords    Platinum Complexes, Chromium Complexes, Molybdenum Complexes, Tungsten Complexes, NMR Spectra 1, 3-Dimethyl-l, 3-diaza 
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 Identifier    ZNB-1994-49b-0100 
 Volume    49 
17Author    Evy Manessi-Zoupa, TheodorosF. Zafiropoulos, SpyrosP. PerlepesRequires cookie*
 Title    Preparation and Properties of Rhodium(III) Complexes with the T etr adentate Ligand N,N'-Bis(2'-py ridi neearbox am ide)-1,8-naphthalene  
 Abstract    Synthetic procedures are described that allow access to a number of new Rh(III) complexes with the tetradentate bis-amide ligand N,N'-bis(2'-pyridinecarboxamide)-1,8-naphthalene (LH2). These complexes have the formulae Rh(LH2)Cl3, Na[RhLX2] • H20 (X = Cl, CN) and [RhLA2]C104 (A = pyridine, 1-methylbenzotriazole). The compounds have been characterized by elemental analyses, conductivity measurements, X-ray powder patterns, spectroscopic (IR, UV/VIS, 'H NMR) studies and electrochemical methods. The neutral amide behaves as a bis-bidentate ligand in the oligomeric or polymeric, octahedral complex Rh(LH,)Cl3. Monomeric, trans octahedral structures are assigned for the complexes o f L2" in the solid state; the doubly deprotonated ligand acts as a tetradentate chelating agent with the four nitrogens as ligating atoms. 
  Reference    (Z. Naturforsch. 49b, 111 [1994]; received June 14 1993) 
  Published    1994 
  Keywords    Rhodium(III) Complexes, Bis-amide Ligands, IR Spectra, 'H NM R Spectra, Cyclic Voltammetry 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0111.pdf 
 Identifier    ZNB-1994-49b-0111 
 Volume    49 
18Author    Anne-Kathrin Duhme, Henry StrasdeitRequires cookie*
 Title    Ligandenmangelkomplexe des Cadmiums. Synthese und spektroskopische Charakterisierung molekularer (Pentafluorphenyl)cadmium-Thiolate und die Struktur des Cubankomplexes [{Cd(C6F5)(SBur)}4] Ligand-Deficient Complexes of Cadmium. Synthesis and Spectroscopic Characterization o f Molecular Pentafluorophenyl Cadmium Thiolates and the Structure o f the Cubane Complex [{Cd(C6F5)(SBuf)}4]  
 Abstract    In toluene, bis(pentafluorophenyl)cadmium(II) and thiols RSH (R = Bu', 2,4,6-Pr'3C6H2, 2,4,6-Bu'3C6H2) react to give soluble pentafluorophenyl cadmium thiolates [(Cd(C6F5)(SR)} J. The compounds [{Cd(C6F 5)(SBu')}4] (1)0 .5 C6H5CH3, [ {Cd(C6F5)(SC6H2Pr'3-2,4,6)} J (2)-ca. 0.25n C6H 5CH3, and [{Cd(C6F5)(SC6H2Bu'3-2,4,6)} J (3) ca. 0.25« C6H5CH3 have been prepared in 65, 59 and 78% yield, respectively. 1-0.5 C6H5CH3 crystallizes in the triclinic space group PI with a = 11,635(1)Ä, b = 11.583(1)Ä, c = 21.480(2)Ä, a = 82.12(1)°, ß = 76.26(1)°, y — 89.35(1)°, and Z = 2. 1 is a cubane-type complex with a {Cd4(/z3-SBur)4}4+ core. Each Cd atom is coordinated by three bridging thiolato ligands and one terminal C6F5 group (C d -S 2.62 A, C d -C 2.15Ä (mean values)). The central C atoms of the Bu'S" ligands of 1 show a remarkable low-field shift o f their 13C N M R resonance (12.3 ppm relative to the value of the free thiol). A characteristic spectral feature of (Cd(C6F5) } + complexes is the large value of the coupling constant 2/ (19F ,13C) o f the ipso-C atom (1, 2: 68 Hz; 3: 67 Hz). The complexes [Cd(C6F5)(SR) + H]+, [Cd(SR)2 + H]+, and [Cd2(SR)3]+ were identified in the Cl mass spectra (/50-butane) of 2 and 3. 
  Reference    (Z. Naturforsch. 49b, 119—127 [1994]; eingegangen am 17. August 1993) 
  Published    1994 
  Keywords    Cadmium Complexes, Thiolates, Crystal Structure, NMR Spectra, Mass Spectra 
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 Identifier    ZNB-1994-49b-0119 
 Volume    49 
19Author    T. Schäfer3, B. Sorg, C. Karalaib, E. HeckerRequires cookie*
 Title    On the Chemistry of Resiniferonol, II [1] Preparation and Bioactivities of 15,16-Dihydrosimplexin and Methods for its Tritium Labeling  
 Abstract    Excoecaria factor 0 1 -the daphnane type polyfunctional diterpene ester 5 /S-hydroxy-6 a,7 a-epoxyresiniferonol-9,13,14-orf/i0-(2,4,6-decatrienoate) -may be obtained in reason­ able amounts from the latex of Excoecaria oppositifolia from South East Asia. 0 1 was par­ tially hydrogenated with H2-Pd/C to yield, by saturation of the three double bonds in the orthoester, and of J 1516 in the diterpene moiety, the new 15,16-dihydro derivative of simple­ xin. The latter is the well known daphnane prototype of polyfunctional diterpene esters occurring in Euphorbiaceae and Thymelaeaceae. 15,16-Dihydrosimplexin (DHS) showed pro­ nounced irritant and tumor promoting activities. By analogous hydrogenation of 0 1 with a mixture of 1H2/3H2 a selectively labeled [3H]DHS was obtained that exhibited a particularly high specific activity of 30 Ci/mmole. Thus it is considered most appropriate for use to study the toxicokinetics and -dynamics of daphnane type diterpene esters. To device an alternative of 3H-labeling of DHS or simplexin (SIM) in position 20 of the diterpene moiety DHS-5-ben-zoate was oxidized by pyridinium chlorochromate. The resultant 20-aldehyde was reduced by sodium borohydride to reconstitute DHS-5-benzoate and, after deprotection, DHS. This route appears appropriate to prepare similarly [20-3H]DHS as well as [20-3H]SIM using sodium [3H]borohydride. 
  Reference    (Z. Naturforsch. 49b, 128—134 [1994]; received September 61993) 
  Published    1994 
  Keywords    Daphnane Derivatives, Diterpene Esters, Simplexin, Skin Irritant Activity, Skin Tumor Promoting Activity 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0128.pdf 
 Identifier    ZNB-1994-49b-0128 
 Volume    49 
20Author    G. Falsone, F. Cateni, M. Baumgartner, V. Lucchini, H. W. Agner, O. SeligmannRequires cookie*
 Title    Constituents of Euphorbiaceae, 13. Comm. [1] Isolation and Structure Elucidation of Five Cerebrosides from Euphorbia characias L  
 Abstract    ,1993 Euphorbiaceae, Cerebrosides, Structure Five cerebrosides B-l -B-4 were isolated from the fraction B, obtained from the latex of Euphorbia characias L. On the basis of spectral evidences and chemical reactions they were characterized as (2S, 3S, 4R, 8Z)-l-0-(/?-D-glucopyranosyl)-2N-[(2'R)-2'-hydroxytetra-cosenoyl]-8 (Z)-octadecene-l,3,4-triol-2-amino (B-l), (2S, 3S, 4R, 8Z)-l-0-(/?-D-gluco-pyranosyl)-2 N-[(2'R)-2'-hydroxyhexacosenoyl]-8(Z)-octadecene-l,3,4-triol-2-amino(B-2), (2 S, 3 S,4 R, 8 Z)-l-0-(/J-D-glucopyranosyl)-2N-[(2'R)-2'-hydroxyoctacosenoyl]-8 (Z)-octa-decene-1,3,4-triol-2-amino (B-3), (2 S, 3 S, 4R, 8Z)-l-0-(/?-D-glucopyranosyl)-2N-[(2'R)-2'-hydroxyhexacosanoyl]-8 (Z)-octadecene-l,3,4-triol-2-amino (B-3a), (2S, 3S, 4R, 8Z)-l-0-(/3-D-glucopyranosyl)-2 N-[(2'R)-2'-hydroxyheptacosanoyl]-8 (Z)-octadecene-l,3,4-triol-2-amino (B-4). Reversed phase column flash chromatography was effective for the isolation of the cere­ brosides. FAB-MS spectrometry, *H NMR, 13C NMR analyses and DQF-COSY and ^ -d e ­ tected HMQC (single bond and multiple bond) experiments and chemical reactions were useful in providing informations for the structure elucidation. 
  Reference    Z. Naturforsch. 49b, 135—140 (1994); received August 30 
  Published    1994 
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 TEI-XML for    default:Reihe_B/49/ZNB-1994-49b-0135.pdf 
 Identifier    ZNB-1994-49b-0135 
 Volume    49 
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