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2000[X]
1Author    M. Ichaela, W. Ilhelm, W. Olfgang Saak, H. Enry StrasdeitRequires cookie*
 Title    Phenylmercury Chloride: Its Single-Crystal X-Ray Structure and Some Aspects of its Biological Chemistry  
 Abstract    A single crystal of phenylmercury chloride (PhHgCl) was obtained by serendipity from a solution of diphenylmercury (HgPh2) and dihydrolipoic acid in tetrahydrofuran / carbon tetrachloride. The crystal structure of PhHgCl is pseudotetragonal. It is best described in the orthorhombic space group Cmma with a = 6.856(1), b = 6.882(1), c = 14.309(2) A (at 193 K), and Z = 4. The Cl-Hg-C moiety of the PhHgCl moleculeois exactly linear. The bond lengths at the Hg atom are Hg-Cl 2.345(2) and Hg-C 2.044(9) Ä. In the crystal, the molecules are arranged in double layers parallel to the a,b plane. In a model medium for the gastric juice (0.1 M DC1 in D 20 / [Dg]dioxan, 37 °C), HgPh2 reacts to form PhHgCl. HgCl2, which would result from complete dearylation, cannot be isolated from the reaction mixture. However, it appears that a small equilibrium concentration of HgCl2 may be present, because on addition of 1,4,7-trithiacyclononane (ttcn) and diethyl ether, the dichloride can be trapped as solid [Hg(ttcn)2][HgCl4]. We estimate that after oral uptake of HgPh2 20 -90% are transformed into PhHgCl in the stomach after 30 min. In tro d u ctio n 
  Reference    (Z. Naturforsch. 55b, 35—38 [2000]; received October 18 1999) 
  Published    2000 
  Keywords    Acidolysis, Bioinorganic Chemistry, Crystal Structure, Mercury, Organomercury Compounds 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0035.pdf 
 Identifier    ZNB-2000-55b-0035 
 Volume    55 
2Author    K. Urt, O. KleppRequires cookie*
 Title    Preparation and Crystal Structure of Na4TiSe4. A Selenotitanate with Discrete Tetrahedral Anions  
 Abstract    Red crystals of Na4TiSe4 were obtained by reacting an intimate mixture of Na2Se, Ti and Se at 750°C. Na4TiSe4 is monoclinic, space group I2/a with a = 24.027(6), b = 7.346(4), c = 21.572(6) A, (3 = 104.52(2)°, Z = 16. Its crystal structure was determined from diffractometer data (AgK a-radiation) and refined to a conventional R of 0.036 for 2673 F0's and 158 variables. The crystal structure is of a new type, characterized by the presence of discrete tetrahedral complex anions, [TiSe,*]4" , which are arranged in slabs parallel to (100). The average Ti-Se bond length is 2.385(1) A. The Na+ cations are in different chalcogen environments with distorted octahedral, square pyramidal or planar configurations, respectively. 
  Reference    (Z. Naturforsch. 55b, 39—44 [2000]; received September 28 1999) 
  Published    2000 
  Keywords    Crystal Structure, Chalcogenides, Titanium, Sodium, Selenium 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0039.pdf 
 Identifier    ZNB-2000-55b-0039 
 Volume    55 
3Author    M. Elanie Piilm, Joachim Becht, R. Einhold TackeRequires cookie*
 Title    Singly Charged A6Si-Silicate Anions with an Si¥5C Skeleton: Syntheses and Crystal Structure Analyses of the Ionic Hexacoordinate Silicon Compounds [Me3NH][F5SiCH2N M e2H ]H 20 and [Me3NH][F5SiCH2NMe3] H2 0  
 Abstract    The zwitterionic A^S/'-tetrafluorosilicates F4SiCH 2N M e2H (1) and F4SiCH2NM e3 (2) behave as Lewis acids and react with [Me3NH]F (molar ratio 1:1) in aqueous solution to yield the ionic A657-pentafluorosilicates [Me3NH][F5SiCH2N M e2H] (3) and [Me3NH][F5SiCH2N M e3l (4), respectively. These hexacoordinate silicon compounds contain singly charged A6S/-silicate anions ([F.sSiCHiNM eiH]-, [F5SiCH2NM e3]-) with an S/F 5 C skeleton. Compounds 3 and 4 were isolated as the crystalline hydrates 3 H 20 (yield 80%) and 4 H 20 (yield 82%) which were structurally characterized by single-crystal X-ray diffraction. The ^/-coordination polyhedra in the crystals of 3 H 20 and 4 H20 are slightly distorted octahedra. 
  Reference    (Z. Naturforsch. 55b, 60—64 [2000]; received October 5 1999) 
  Published    2000 
  Keywords    Pentacoordinate Silicon, Hexacoordinate Silicon, Lewis Acid, Crystal Structure 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0060.pdf 
 Identifier    ZNB-2000-55b-0060 
 Volume    55 
4Author    Henri Brunner, M. Arkus, N. Iem Etz, M. Anfred ZabelRequires cookie*
 Title    Optisch aktive Ubergangsmetall-Komplexe, 122 [1]. Synthese von Palladium(II)-Schiff-Base-Komplexen -intramolekulare Wechselwirkungen O ptically Active Transition M etal C om plexes, 122 [1], Synthesis of Palladium (II) Com plexes w ith Schiff B ase Ligands -Intram olecular Interactions  
 Abstract    Imines of salicylaldehyde and 2,6-diformyl-p-cresol have been used as ligands in palla­ d iu m ^) complexes. Enantiomerically pure ligands give enantiomerically pure complexes, racemic ligands give racemates and meso-forms. Differences between the respective isomers of the ligands within the complexes and between the diastereomers of the complexes were investigated. Crystal structure analyses established the trans configuration at the metal center. 
  Reference    Z. Naturforsch. 55b, 145—154 (2000); eingegangen am 25. Oktober 1999 
  Published    2000 
  Keywords    Schiff Bases, Palladium(II) Complexes, Diastereomers, Crystal Structure 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0145.pdf 
 Identifier    ZNB-2000-55b-0145 
 Volume    55 
5Author    C. Bender, D. W. Ulff-M, H. Older, F. Vogt, M. M. Ritschl, EiselRequires cookie*
 Title    Synthese und Kristallstruktur des Bromdifluormethyl-triphenyl- phosphoniumbromids, [(C6H5)3 PCF2Br]+ Br" Synthesis and Crystal Structure o f B rom odifluorom ethyl-triphenylphosphonium Brom ide, [(C6H5)3PC F2Br]+ Br~  
 Abstract    Difluorobromomethyl-triphenylphosphonium bromide [(C6H5)3PCF2Br]+ Br-(1) has been prepared by the reaction of triphenylphosphine with dibromodifluoro-methane in acetonitrile or methylene chloride. The colorless crystals are monoclinic, space group P 2,/n, Z=4, a = 1067.1(2), b = 1488,5(2), c = 1178,2(2) pm, ß = 95,67(3)°. The lattice contains Br~ anions and [(C6H5)3PCF2Br]+ cations with a Br-Br distance of 322,33(11) pm.. For the title compound the results of AM 1, PM 3 ,and MNDO calculations are in good agreement with corresponding values determined by the X-ray analysis only in the case of PM 3. The yellow-red [(C6H5)3PCF2Br]+ Br3~ (2) has been obtained by treating 1 with equimolar quantities of elemental bromine in methylene chloride solution. E inleitung 
  Reference    Z. Naturforsch. 55b, 167—170 (2000); eingegangen am 28. Oktober 1999 
  Published    2000 
  Keywords    Bromodifluoromethyl-triphenylphosphonium Bromide, Synthesis, Crystal Structure 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0167.pdf 
 Identifier    ZNB-2000-55b-0167 
 Volume    55 
6Author    AlfonsoC. Astiñeiras-C, Am, IgnacioS. De L, Cueva -Torregrosab, JosefaM. G Onzález-Pérezb, A. Urora, G. Sicilia-Z, ElenaB. Afrab, A. Ugella-, JuanN. Ltam Iranob, S-G Icló, UtiérrezbRequires cookie*
 Title    Synthesis, Structure and Properties of / > o/j-[(Ar-(2-Hydroxyethyl)- Af'-carboxymethyl-l,2-ethyIenediamine-AyV'-Diacetato)copper(II) Hydrate], {[Cu(Hhedta)] * H20 } n  
 Abstract    The stoichiometric reaction of /V-(2-hydroxyethyl)-1,2-ethylenediamine-/V,/V,7V'-triacetic acid [hbhedta = (H0CH2CH2)(H02CCH2)NC2H4N(CH2C02H)2)] and copper(II) hydroxy-carbo-nate in water yields crystalline samples of /?0/v-{(/V-(2-hydroxyethyl)-/V'-carboxymethyl-l,2-ethylenediamine-./V,./V'-diacetato)copper(II) hydrate}, {[Cu(Hhedta)] TTOjn (I)-The com­ pound was studied by TG analysis (with FT-IR study of the evolved gases), IR, electronic and ESR spectra, magnetic susceptibility data and single crystal X-ray diffraction methods. It crystallises in the orthorhombic system, space group Fdd2 (a = 21.906(2), b = 36.602(4), c = 6.928(1) A, Z = 16, and final R\ = 0.029 for 1554 independent reflections). The Cu(II) atom exhibits a very distorted octahedral coordination (type 4+1 + 1). The Hhedta ligand plays a yV,yV',0,C>',(9"-pentadentate chelating role as well as a O,0'-carboxylate bridging one and has a free /V-carboxymethyl arm. The bridging carboxylate group of the Hhedta ligand leads to polymeric chains {[Cu(Hhedta)] H20}n parallel the c axis. A hydrogen bonding network involves all O-H polar bonds (non-ionised carboxylic and alcoholic hydroxyl groups and water molecules). The structure reveals the preferred formation of a copper(II)-(/V-2-hydroxyethyl-amino) or copper(II)-(ethanolamino) versus a copper(II)-(/V-carboxymethylamino) chelate ring. In tro d u c tio n 
  Reference    Z. Naturforsch. 55b, 171—177 (2000); received October 10 1999 
  Published    2000 
  Keywords    Copper(II) Chelate, Crystal Structure, Amino-polycarboxylates, Ethanolamine 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0171.pdf 
 Identifier    ZNB-2000-55b-0171 
 Volume    55 
7Author    Gerhard Bringmanna, Doris Feineis3, Ralph Brückner, Eva-Maria Petersb, Karl PetersbRequires cookie*
 Title    2-Hexanoyl-l-tribromomethyl-l,2,3,4-tetrahydro-/?-carboline: Crystal Structure Analysis of a Potent Inhibitor of Complex I of Mitochondrial Respiration  
 Abstract    The molecular structure of the title com pound 2-hexanoyl-l-tribromomethyl-l,2,3,4-tetra-hydro-/3-carboline (3), a potent inhibitor of complex I of the mammalian mitochondrial respi­ ratory chain, has been studied by single-crystal X-ray diffraction analysis. In the crystal, two heterochiral molecules of 3 (i.e., one R-and one S-configured molecule each) were found to be connected with one other in pairs via two intermolecular hydrogen bonds [0(215) • • • H(212)' and 0(215)' • • • H(212)] to form an overall achiral 'dimeric' subunit. 
  Reference    (Z. Naturforsch. 55b, 94—99 [2000]; received O ctober 21 1999) 
  Published    2000 
  Keywords    Crystal Structure, Bromal-Derived Tetrahydro-ß-carbolines Mitochondrial Respiration, Parkinson's Disease, Neurotoxicity 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0094.pdf 
 Identifier    ZNB-2000-55b-0094 
 Volume    55 
8Author    W. PreetzRequires cookie*
 Title    Kristallstrukturen  
 Abstract    , Schwingungsspektren und Normalkoordinatenanalyse von (Ph3PNPPh3)[O sF5C l] CH2Cl2 und cis-(Ph3PNPPh3)[OsF4C\2]C H 2Ch Crystal Structures, Vibrational Spectra and N orm al C oordinate A nalysis o f (Ph3P N PP h3) [O sF5Cl] C H 2C12 and ris-(P h 3PN PPh3)[O sF4C l2]-CH2C l2 B. L orenzen By careful oxidation of the pure fluorochloroosmates(IV) with BrF3 in dichloromethane the mixed pentavalent complex anions [OsF5C1]_ and m -[O sF 4Cl2] _ are formed. X-ray structure determinations on single crystals have been performed of (Ph3PNPPh3)[OsF5C l]C H 2Cl2 (1) (triclinic, space group P i, a = 12.153(5), b = 12.387(5), c = 14.229(5) A , a = 70.07(1), ß = 65.46(1), 7 = 72.87(1)°, Z = 2) and ds-(P h 3PNPPh3)[OsF4Cl2] C H 2Cl2 (2) (triclinic, space group P i, a = 11.987(2) b = 13.083(2), c = 14.456(2) A , a = 66.30(1), ß = 65.47(1), 7 = 71.22(1)°, Z = 2). Based on the molecular parameters of the X-ray determinations the IR and Raman spectra for the anions of 1 and 2 have been assigned by normal coordinate analysis. Due to the mutual trans influences the valence force constants of asymmetrically coordinated octahedral axes F*-Os-Cl' differ from those of the symmetric F-Os-F axes. The data are for 1: fd(OsF*) = 3.95, fd(OsF) = 4.07, fd(OsCl') = 2.51 and for 2: fd(OsF*) = 3.45, fd(OsF) = 3.97, fd(OsCl') = 2.42 mdyn/A. 
  Reference    (Z. Naturforsch. 55b, 45—50 [2000]; eingegangen am 9. November 1999) 
  Published    2000 
  Keywords    Pentachlorofluoroosmate(V), ds-Tetrachlorodifluoroosmate(V), Crystal Structure, Vibrational Spectra, Normal Coordinate Analyses 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0045.pdf 
 Identifier    ZNB-2000-55b-0045 
 Volume    55 
9Author    Jürgen Schatz3, Frank Schildbacha, AxelL.Requires cookie*
 Title    The Inclusion of Carbon Disulfide in /?-rerf-Butylcalix[4]-and [6 ]arene - A Combined Crystallographic and Vibrational Spectroscopic Study  
 Abstract    en tzb, Sylvia R a stä tte rb, Joachim Schilling5, Jö rg D o rm an n c, A n d reas R uoffc, and Tony D eb ae rd em ae k erd The inclusion complexes formed from carbon disulfide and /?-r£7-r-butylcalix[4]arene (1 C S 2) or /?-rm-butylcalix[6]arene (2-C S2) were investigated by X-ray crystal structure analysis, infrared (IR) and Raman spectroscopy. The complex 1 C S 2 crystallises in the space group P4/n, 2 C S 2 in the space group P2xln. In case of /?-rm-butylcalix[4]arene as host the carbon disulfide molecule is included in the cavity. In the crystal structure of p-rm -butylcali-x[6]arene clathrate, self-com plexation o f one rm-butyl group in the cavity o f another ca-lix[6]arene can be observed. Due to inclusion, the symmetry of CS2 is lowered both in the p-rm -butylcalix[4]arene and p-rm-butylcalix[6]arene case causing significant shifts in the fully assigned infrared and Raman spectra. 
  Reference    Z. Naturforsch. 55b, 213—221 (2000); received N ovem ber 16. 1999 
  Published    2000 
  Keywords    p-rerz-Butylcalixarenes, Inclusion Complexes, Crystal Structure, IR Data, Raman Data 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0213.pdf 
 Identifier    ZNB-2000-55b-0213 
 Volume    55 
10Author    M. Ath, O. S. EngeRequires cookie*
 Title    A Conformational Study of 5,10,15,20-Tetraalkyl-22//+,24//+-porphyrindiium Salts (Dication Salts)  
 Abstract    N-protonation of 5,10,15,20-tetraalkylporphyrins with n-butyl, isobutyl, isopropyl, 1-ethyl-propyl or ferf-butyl substituents yields the respective 22,24-dihydroporphyrins (22//+,24//+-porphyrindiium salts) that exhibit highly nonplanar conformations. Depending on the steric demand of the meso substituents, the free base porphyrins have planar to moderately ruffled macrocycles (primary or secondary alkyl residues) or are severely ruffled (tertiary alkyl resi­ dues). X-ray crystallographic studies show that protonation of porphyrins with «-Bu (2), i-Pr (3) or EtPr (4) substituents leads to steric congestion of the core resulting in symmetric, saddle distorted macrocycles as evidenced by average displacements of the Cb positions from the mean plane ranging from 0.79 to 1.01 A. The structures observed for these porphyrin diacids are very similar in distortion mode and degree of nonplanarity to 5,10,15,20-tetraaryl-22f/+,24//+-porphyrindiium salts and to 2,3,7,8,12,13,17,18-octaalkyl-5,10,15,20-tetraaryl-porphyrins. In contrast, protonation of the highly ruffled 5,10,15,20-tetrakis(teA-r-butyl)porph-yrin results in a switch of the conformational distortion mode. The dication 6 shows both saddle distortion (Cb displacements -1.3 A) and ruffling of the macrocycle (Cm displacements of approx. 0.48 A). Thus, the need to accomodate four N-H units in the porphyrin core with its associated out-of-plane tilting of the pyrrole rings and the steric strain induced at the meso carbon atoms results in a highly nonplanar porphyrin with mixed distortion modes. 
  Reference    Z. Naturforsch. 55b, 336—344 (2000); received January 20 2000 
  Published    2000 
  Keywords    Porphyrins, Steric Strain, Porphyrin Dications, Crystal Structure, Conformational Analysis, 22, 24-Dihydroporphyrins 
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 TEI-XML for    default:Reihe_B/55/ZNB-2000-55b-0336.pdf 
 Identifier    ZNB-2000-55b-0336 
 Volume    55