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1983 (307)
121Author    Bernhard Ciommer, Helmut SchwarzRequires cookie*
 Title    Zur intermediären Existenz von Ethylenfluoronium-Ionen in der Gasphase On the Intermediary Existence of Gaseous Ethylen Fluoronium Ions  
 Abstract    The long-sought ethylen fluoronium ion (2) is generated as an intermediate in the dissociative ionization of l-fluoro-2-(^-methyl)phenoxy ethane (4). However, prior to collisionally induced dissociation 2 undergoes ring-opening, associated with hydrogen migration, to form 1-fluoroethyl cation (3). Other decomposition pathways of the molecular ions of 4 involve (i) direct formation of 3 via a combination of C-O-cleavage (loss of ArO -) and [1,2] hydrogen migration (18%) and (ii) complete positional loss of the a-and ß-methylene hydrogen atoms (34%). The remaining 48% of the molecular ions of 4 dissociate via anchimeric assistance of the fluorine in the elimination of ArO -, thus giving rise to the formation of 2. 
  Reference    Z. Naturforsch. 38b, 635—638 (1983); eingegangen am 23. Dezember 1982 
  Published    1983 
  Keywords    Fluoronium Ions, Neighbouring Group Participation, Gaseous Ions, Collisional Activation, Mass Spectrometry 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0635.pdf 
 Identifier    ZNB-1983-38b-0635 
 Volume    38 
122Author    Galal Eldin, Hamza Elgemeie, Anwar Samier, Ibraheim Elees, MohamedHilmy Elsakka, ElnagdiRequires cookie*
 Title    Activated Nitriles in Heterocyclic Synthesis: The Reaction of Cinnamonitrile Derivatives with Active Methylene Reagents  
 Abstract    The reaction of substituted cinnamonitrile derivatives with cyanoacetanilide and ethyl acetoacetate is reported. Several new polyfunctional pyridine and pyran derivatives could be synthesised. The structures of the prepared compounds and the mechanisms of their formation is reported. 
  Reference    Z. Naturforsch. 38b, 639—642 (1983); received November 2 1982 
  Published    1983 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0639.pdf 
 Identifier    ZNB-1983-38b-0639 
 Volume    38 
123Author    Abdussalam Maihub, JayW. Grate, HuiBi Xu, GerhardN. SchrauzerRequires cookie*
 Title    Amino Acids as Substrates in the Synthesis of Substituted Organocobalamins [1]  
 Abstract    Amino Acids, Substituted Organocobalamins The amino acids alanine, valine, leucine, isoleucine, norvaline, a-amino butyric acid, and /3-methyl aspartic acid are utilized as substrates for organocobalamin syntheses under "oxidizing/reducing" conditions. In the presence of V+ 3 as the reducing agent, free radicals are generated by the reaction of oxygen radicals with the amino acids through hydrogen atom abstraction. These amino acid radicals then combine with the cobalt atom of vitamin Bi2r to yield the respective organocobalamins. The cobalamin obtained from the reaction of /S-methyl aspartic acid is a possible intermediate in the coenzyme B12 dependent skeletal rearrangement of /S-methyl aspartic acid to glutamic acid. HPLC analysis of the cobal-amins prepared from D,L-alanine indicates that the corrin ligand is relatively ineffective at promoting asymmetric syntheses under these conditions. 
  Reference    Z. Naturforsch. 38b, 643—647 (1983); received December 21 1982 
  Published    1983 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0643.pdf 
 Identifier    ZNB-1983-38b-0643 
 Volume    38 
124Author    C. C. Battaglia, H. Frazier Iii, Kisch, C. Krüger, Herrn Professor, G. 0. SchenckRequires cookie*
 Title     
 Abstract    Photocycloaddition, Intramolecular Metal Catalysis, X-Ray A tricyclic l,l,l-tricarbonyl-2,3,l-diazaferrole derivative (1) reacts photochemically with 1,3-dienes with formation of [4 + 2]-cycloadducts. Introduction of substituents in the 1-or 1,4-positions of the diene or of electron releasing groups in the dienophile results in an inhibition of the cycloaddition. The reaction proceeds stepwise via photodissociation of carbon monoxide, coordination of the diene to iron, intramolecular photocycloaddition, and re-uptake of carbon monoxide. No cycloaddition occurs if the complexed diene is allowed to react thermally. X-ray structural analyses of 1 and its cycloadduct with 2,3-dimethylbutadiene (3d) reveal the presence of a novel type of three electron metal -diazene bond for both compounds and delocalized bonding for the diazaferrole 1. 
  Reference    Z. Naturforsch. 38b, 648—654 (1983); eingegangen am 21. Dezember 1982 
  Published    1983 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0648.pdf 
 Identifier    ZNB-1983-38b-0648 
 Volume    38 
125Author    Thomas Hättich, Udo KunzeRequires cookie*
 Title    Trialkylstannanedithi ocarboxy lato Rhenium(I) Complexes [1]  
  Reference    Z. Naturforsch. 38b, 655—657 (1983); received February 1 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0655_n.pdf 
 Identifier    ZNB-1983-38b-0655_n 
 Volume    38 
126Author    Macki Kaloga, Ilona ChristiansenRequires cookie*
 Title    Photodimerisation of 6 -1 rans-Styry 1 -4 -methoxy-2 -pyr one (= 5,6-Dehydrokawain) and cis-Isomerisation of (±)-Kawain  
 Abstract    The photochemical transformation of 5,6-Dehydrokawain (1) to rel-(lR,6S,7S,8S)-5-methoxy-7-phenyl-8-[6-(4-methoxy-2-pyronyl)]-l-(E)-styryl-2-oxabicyclo[4,2,0]octa-4-en-3-one (2) by irradiation with a light bulb [1] is con-firmed. Kawain (3) turns out to be resistent to photochemical reaction in several tests. During irradiation by a Hg-lamp a transformation to cis-Kawain (4) takes place, however. 
  Reference    Z. Naturforsch. 38b, 658—659 (1983); eingegangen am 13. November 1982 und 31. Januar 1983 
  Published    1983 
  Keywords    Aniba-Dimer-A, 5, 6-Dehydrokawain, cis-Kawain, Photodimerisation, Photoisomerisation 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0658_n.pdf 
 Identifier    ZNB-1983-38b-0658_n 
 Volume    38 
127Author    H.E JRequires cookie*
 Title    Viqar Uddin Ahmad* and Sabiha Qazi  
 Abstract    The absolute configuration of julifloridine is proposed to be 2 R, 3 R, 6 R through 13 C Spectra, m NMR Spectra, 
  Reference    Z. Naturforsch. 38b, 660 (1983); received December 28 1982 
  Published    1983 
  Keywords    Prosopis juliflora, Julifloridine, Absolute Configuration 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0660_n.pdf 
 Identifier    ZNB-1983-38b-0660_n 
 Volume    38 
128Author    Berthold Brazel, Rudolf HoppeRequires cookie*
 Title    Über Oxoplumbate(IV) Die Kristallstruktur von HT-Li2Pb03 [1] The Crystal Structure of HT-Li2Pb03 [1]  
 Abstract    Single crystals of HT-Li2Pb03 have been prepared by heating of mixtures of Rb2Pb03 and Li20 [Ag-cylinders, 600 °C, 100 d]. The structure determination [1005 symmetry independent l0(hkl), R = 5.85%, Rw = 5.35%, confirms space group C2/c with a = 548.60(16), b = 949.51(22), c = 1027.35(27) pm, ß = 100.11(3)°, drö = 6.78 g • cm-3 , dpyk = 6.80 g • cm-3 , Z — 8. The NaCl-type structure variant is characterized by alter-nating layers of Li+ and Pb 4+ /Li + cations, which are all octahedrally coordinated. Effective Coordination Numbers, ECoN are calculated via Mean Fictive Ionic Radii, MEFIR. 
  Reference    Z. Naturforsch. 38b, 661—664 (1983); eingegangen am 15. Februar 1983 
  Published    1983 
  Keywords    Lithiumoxoplumbate(IV) (High Temperature Form), Single Crystal Preparation, Structure 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0661.pdf 
 Identifier    ZNB-1983-38b-0661 
 Volume    38 
129Author    Ludwig Roß, Martin DrägerRequires cookie*
 Title    Phases of Decaphenylcyclopentagermane (Ph2Ge)s [1]  
 Abstract    (Pb^Ges) can be obtained from solutions in five crystalline phases, two pure and three including solvent of crystallization. This is lost at 70 °C. At 190 °C all phases transform into a plastic crystalline phase. For this tetragonal phase a gear wheel model for librations of the molecules is developed. The crystal structure of triclinic (Ph2Ge)s has been determined and refined to R = 0.050. The molecule has a flexible conformation in accordance with a better solubility than exhibited by the homologous rings (Ph2Ge)4 and (Ph2Ge)6 containing rigid normal conformations. The arrangement of phenyl groups is either parallel or perpendicular for both cases intra-and intermolecular. The compound (Ph2Ge)6 attains a plastic crystalline state at 346 °C. 
  Reference    Z. Naturforsch. 38b, 665—673 (1983); eingegangen am 28. Januar 1983 
  Published    1983 
  Keywords    Germanium, Homocycle, Conformation, Plastic Crystalline State 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0665.pdf 
 Identifier    ZNB-1983-38b-0665 
 Volume    38 
130Author    Gerhard Thiele, Kurt WittmannRequires cookie*
 Title    Über Hydraziniumsalze von Iodoplatinaten On Hydrazinium Salts of Iodoplatinates  
 Abstract    The new compounds (N2H5)2Ptl6 and (^Hs^Ptls • H2O were obtained by reaction of H2PtCl6 with N2H5CI and HI in aqueous solutions. In the crystal structure of the ortho -rhombic bis[hydrazinium(+I)]hexaiodoplatinate(IV) (^Hs^Ptle the N2H5+ cations and Ptlö 2-anions build up a K^PtClß-like arrangement. Bis[hydrazinium(+I)]pentaiodo-platinate(II,IV)hydrate, (N2Hs)2Ptl5 • H20, is classed with the group of linear chain mixed-valence platinum complexes which have highly anisotropic properties. In the crystal structure are structurally undistinguishable Ptl4-units (Pt-I = 264 pm) connected by asymmetric I-bridges (Pt-I = 270 pm and 338 pm) to 1 [Ptl4l2/2] chains. 
  Reference    Z. Naturforsch. 38b, 674—679 (1983); eingegangen am 15. Februar 1983 
  Published    1983 
  Keywords    Iodoplatinates, Hydrazinium Salt, Mixed-Valence Compound, Crystal Structure 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0674.pdf 
 Identifier    ZNB-1983-38b-0674 
 Volume    38 
131Author    W. Preetz, M. BrunsRequires cookie*
 Title    Darstellung und spektroskopische Charakterisierung von Hexachloroosmat(V)  
 Abstract    (TEA)[OSC16] is formed quantitatively by heating solid £RARAS-(TEA)[OsX4(CO)2] (X = Br, I) in a stream of chlorine at 120 °C, and can be purified by recrystallisation from CH2CI2 without decomposition. It is reduced immediately by acetone, methanol, CU, Br~, I -to give [OsCl6] 2 -. The standard potential [OsCl6] -/[OsCl6] 2 ~ in acetonitrile referred to the saturated mercury-mercurous sulphate electrode is 0.840 V. The IR and Ra bands of (TEA)[OsCl6], assigned according to point group Oh, are shifted to higher frequencies compared with (TEA)2[OsCle]. The excitation at 488.0 nm gives a resonance Raman spectrum exhibiting 6 overtones of vi and combination tones up to 4 J»I + v-0. The electronic absorption spectrum shows five spin-forbidden intraconfigurational transitions coupled with odd vibrational modes in the near infrared region. The spin-allowed 4 A2g -> 4 T2g, 4 Tig-transitions are observed at 347 and 305 nm. The excited levels can be fitted with the parameters A = 28500 cm-1 , B = 340 cm-1 , $ = 2500 cm 4 , allowing to calculate the nephel-auxetic ratio /J55 to 0.47. In the visible region extensive charge transfer transitions are observed. Based on the strong oxidizing character of Os(V) there is a bathochromic shift of corresponding bands of [OsClß]-in relation to [OsC^] 2-of about 6600 cm -1 and to the isoelectronic [ReCle] 2-of about 13700 cm -1 , respectively. From Jitiu->dt2g the optical electronegativity is calculated to a0pt(Os v) — 2.49. 
  Reference    Z. Naturforsch. 38b, 680—686 (1983); eingegangen am 10. Februar 1983 
  Published    1983 
  Keywords    Hexachloroosmate(V), Electronic Spectra, IR Spectra, Raman Spectra 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0680.pdf 
 Identifier    ZNB-1983-38b-0680 
 Volume    38 
132Author    Hidenari Inoue, Ekkehard FluckRequires cookie*
 Title    Mößbauer-und Röntgenphotoelektronen-spektroskopische Untersuchungen an Berlinerblau-Analoga des Typs Fe[M B (CN)6] Mößbauer and X-Ray Photoelectron Spectroscopic Studies on Prussian Blue Analogs of the Type Fe[M B (CN)6]  
 Abstract    Prussian Blue analogs of the type Fe[M B (CN)e] (M B = Pd and Pt) crystallize in the face-centered cubic system: space group Fm3m-0^, Z = 4. Magnetochemical and Mößbauer spectroscopic measurements have revealed that nitrogen-coordinated iron(II) ions and carbon-coordinated M B (IV) ions are in the high spin state and in the low spin state, respectively, in the temperature range 4.2 to 300 K. Upon the formation of Fe[M B (CN)ß] from K2[M B (CN)6], the binding energies of N Is, Pd 3d5/2 and Pt 4f7/2 increase while the C 1 s binding energy decreases. This tendency could be interpreted in terms of the inductive effect of iron(II) ions attached to the nitrogen end of cyanide ligands. 
  Reference    Z. Naturforsch. 38b, 687—691 (1983); eingegangen am 7. Februar 1983 
  Published    1983 
  Keywords    Mößbauer Spectra, X-Ray Photoelectron Spectra, Prussian Blue Analogs 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0687.pdf 
 Identifier    ZNB-1983-38b-0687 
 Volume    38 
133Author    Heinrich NöthRequires cookie*
 Title    Beiträge zur Chemie des Bors, 133 [1] Molekül-und Kristallstruktur von Tris(methylanilido)boran Contributions to the Chemistry of Boron, 133 [1] Molecular and Crystal Structure of Tris(methylanilido) Borane  
 Abstract    Tris(methylanilido)borane, X-Ray Structure The title compound crystallizes in the rhombohedral space group R3, Z = 1. The boron atom occupies a special position on the threefold axis therefore imposing C3 symmetry to the molecule. The C2BN plane is twisted relative to the BN3 plane by 37.1°, and the BN bond length of 144.8(3) pm is on the upper limit of BN bond lengths found for other triaminoborane systems. 
  Reference    Z. Naturforsch. 38b, 692—695 (1983); eingegangen am 16. Februar 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0692.pdf 
 Identifier    ZNB-1983-38b-0692 
 Volume    38 
134Author    SiegmundL. Braun, Edith Dürrneyer, Karl Jacob, Wolfgang VogtRequires cookie*
 Title    Iodination of Aniline Using Thallium(III)-trifluoroacetate and Potassium Iodide  
 Abstract    Iodination, Aniline, £>-Iodo-aniline, Thallium(III)-trifluoroacetate A new procedure for a specific micro-synthesis of p-iodo-aniline has been developed. It consists of the reaction of aniline with tliallium(III)-trifluoroacetate followed by the iodination with aqueous potassium iodide. 
  Reference    Z. Naturforsch. 38b, 696—697 (1983); received February 2 1983 
  Published    1983 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0696.pdf 
 Identifier    ZNB-1983-38b-0696 
 Volume    38 
135Author    Gerhard Jäger, PeterG. Jones, GeorgeM. Sheldrick, Einhard SchwarzmannRequires cookie*
 Title    Darstellung und Kristallstruktur von Antimon(V)oxidhydroxid HSb308 Preparation and Crystal Structure of the Antimony(V) Oxide Hydroxide HSb30g  
 Abstract    Colourless crystals of HSb3Os were prepared by hydrothermal methods from Sb205. The crystal structure [P2/n, a = 945.6(2), b = 869.1(2), c = 990.9(2) pm, ß = 90.25(2)°, Z = 6. R = 0.045] was determined from diffractometer measurements. Distorted SbOe octahedra are linked through vertices and edges to form a three-dimensional polymer of pseudo-orthorhombic symmetry. The hydrogen atoms could not be located. 
  Reference    Z. Naturforsch. 38b, 698—701 (1983); eingegangen am 14. Februar 1983 
  Published    1983 
  Keywords    Crystal Structure, Antimony(V), Oxide, Hydroxide, Hydrothermal Synthesis 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0698.pdf 
 Identifier    ZNB-1983-38b-0698 
 Volume    38 
136Author    Hans-Martin Schiebel, Reinhard Schmutzler, Dietmar Schomburg, Ulrich WermuthRequires cookie*
 Title    Synthesis and Crystal Structure Determination of a X 3 P X 5 P-Phosphorane of a Novel Type  
 Abstract    The synthesis of a 2 3 P-substituted phosphorane involving direct substitution of a Ph2P group at / 5 P by the reaction of a chlorophosphorane with Ph2PSiMe3 is described; the identity of this novel compound is established by NMR and mass spectroscopy, and by a single crystal X-ray diffraction study. 
  Reference    Z. Naturforsch. 38b, 702—704 (1983); received March 7 1983 
  Published    1983 
  Keywords    Phosphorane, NMR, Mass Spectroscopy, X-Ray 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0702.pdf 
 Identifier    ZNB-1983-38b-0702 
 Volume    38 
137Author    Herbert Schumann, Karl-Heinz Köhricht, Manfred MeißnerRequires cookie*
 Title    Organometallphosphin-substituierte Übergangsmetallkomplexe, XIX [1] Carbonyl-dinitrosyl-organometallphosphin-eisen-Komplexe Organometalphosphine-substituted Transition Metal Complexes, XIX [1] Carbonyl Dinitrosyl Organometalphosphine Iron Complexes Die Komplexe der Pseudonickelcarbonyl-Serie  
 Abstract    The reactions of dicarbonyl dinitrosyl iron with tri-fertf-butylphosphine, di(feri-butyl)-trimethylsilyl-, -germyl-, -stannyl-phosphine, ferZ-butyl-bis(trimethylsilyl)-, -(germyl)-, -(stannyl)phosphine, as well as with tris(trimethylsilyl)-, -(germyl)-, and -(stannyl)phos-phine result in the elimination of one CO ligand and the formation of the corresponding carbonyl dinitrosyl organometalphosphine iron complexes. The IR, X H, 31 P, 13 C, and 119 Sn NMR spectra of the new complexes are reported and discussed. 
  Reference    Z. Naturforsch. 38b, 705—710 (1983); eingegangen am 22. Februar 1983 
  Published    1983 
  Keywords    Organometal Phosphines, Carbonyl Dinitrosyl Iron Complexes, NMR Spectra 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0705.pdf 
 Identifier    ZNB-1983-38b-0705 
 Volume    38 
138Author    Wolfgang Malisch, Herbert Blau, Peter Weickert, Karl-Heinz GrießmannRequires cookie*
 Title    Zur Reaktion von Metall-koordiniertem Kohlenmonoxid mit Yliden, X [1] /3-Phosphoniocarben-, ß-Phosphonio vinyl-und Phosphor-Ylid-Komplexe des Chroms und Cobalts aus Tetramethylphosphonium- [(trimethylphosphoranyliden)acetyl-metallaten] Reactions of Metal Coordinated Carbon Monoxide with Ylides, X [1] ^-Phosphoniocarbene, /9-Phosphoniovinyl and Phosphorus Ylide Complexes of Chromium and Cobalt Deriving from Tetramethylphosphonium [(trimethylphosphoranyliden)- acetyl-metallates]  
 Abstract    The reaction of Cp(CO)2(NO)Cr with Me3P = CH2 yields the tetramethylphosphonium -[(trimethylphosphoranyliden)acetyl-Chromate] Me4P[Cp (CO)(NO)Cr-C(O)-CH = PMe3] (1) via ylide addition at the carbonyl carbon and transylidation. A reversible equilibrium is established between 1 and the starting materials, which is responsible for the facile conversion of 1 into the ylide complex Cp(CO)(NO)Cr-CH2PMe3 (2) on photolysis. In the presence of Mel, 1 is degradated to [Me4P]I, [Me3PEt]I, [Me2PEt2]I and Cp(CO)2(NO)Cr. Treatment of 1 with an equimolar amount of Me0S02F leads to the formation of the "zwitterionic" phosphoniovinyl complexes Cp(CO)(NO)Cr-C(OMe) = CH-PMe3 (3a) and Cp(CO)(NO)Cr-C(OMe) = C(Me)-PMe3 (3b). With excess Me0S02F the phosphoniocarbene complex [Cp(C0)(N0)Cr = C(0Me)-CH(Me)-PMe3]S03F (4a) is obtained. Me3P = CH2 de-protonates 4a to 3b, which adds HCl to give [Cp(CO)(NO)Cr=C(OMe)-CH(Me)-PMe3]Cl (4b). The phosphonium cobaltacylates Me4P[(C0)(N0)(L)C0-C(0)-CH = PMe3] (5a, b), generated from the cobalt complex (CO)2(NO)(L)Co (L = CO, Me3P) and Me3P = CH2, readily transform to the ylide complexes (CO)(NO)(L)Co-CH2-PMe3 (6a, b). MeX (X = I, S03F) cleaves 6b to give (CO)2(NO)(Me3P)Co and [Me3PEt]X. The new complexes are characterized by elementary analysis and spectroscopy. 
  Reference    Z. Naturforsch. 38b, 711—718 (1983); eingegangen am 18. Januar 1983 
  Published    1983 
  Keywords    Carbonmonoxide Conversion, Vinyl Complexes, Carbene Complexes, Ambidentate Nucleophilic Reactivity 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0711.pdf 
 Identifier    ZNB-1983-38b-0711 
 Volume    38 
139Author    Ralf Steudel, Eva-Maria StraussRequires cookie*
 Title    Chromatographische Trennung schwefelhaltiger Heterocyclen der Typen (CH2)nSM und Se"S8_m mittels HPLC [1] Chromatographie Separation of Sulfur Containing Heterocycles of Type (CH2)"Sm and SenS8_n by HPLC [1]  
 Abstract    The Separation of a number of cyclic methylene sulfides and selenides by reversed-phase high-pressure liquid chromatography is reported. The retention times as well as the capacity factors depend in a systematic way on the ring size, the number and kind of chalcogen atoms, and the number of heteronuclear bonds within the ring. These relation-ships are used to assign the chromatograms of cyclic selenium sulfides of type SeraS8-n (n = 1-8) prepared in a new reaction from Se2Cl2, SC12 and potassium iodide and containing all selenium atoms in neighboring positions. 
  Reference    Z. Naturforsch. 38b, 719—725 (1983); eingegangen am 9. Februar 1983 
  Published    1983 
  Keywords    HPLC, Methylene Sulfides, Methylene Selenides, Selenium Sulfides, Sulfur Heterocycles 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0719.pdf 
 Identifier    ZNB-1983-38b-0719 
 Volume    38 
140Author    Ekkehard Lindner, Efstathios TamoutsidisRequires cookie*
 Title    Das reaktive Verhalten von phenyl-und imidazolylsubstituierten Propenoyldiphenylphosphanen The Reactive Behaviour of Phenyl and Imidazolyl Substituted Propenoyldiphenylphosphanes  
 Abstract    The unsaturated acylphosphanes RC(0)PPh2 (4a, b') [R = Ph-CH = CH (a), C3H4N2(Cl)-C(Ph) = CH (b')J are obtained by reaction of RC(0)C1 (3a, b') with (CH3)3SiPPh2. The preparation of 3 b' is possible by addition of imidazole to the triple bond of Ph-C=C-C(0)0C2H5 and subsequent hydrolysis of RC(0)0C2H5 (lb) [R = C3H3N2-C(Ph) = CH (b)] and chlorination of RC02H (2b'). From 4a and imidazole the imidazolide Ph2P(Ph)CH-CH2-C(0)-N2C3H3 (5) is formed which can be oxidized to give Ph2(0)P(Ph)CH-CH2-C(0)-N2C3H3 (6). 4a is coordinated in two different ways to transition metals. A 1:1 molar ratio of 4 a and LwMnTHF [LreMn = (iy 5 -C5H5)Mn(CO)2] yields the P-coordinated complex RC(0)P(Ph2)-MnL" (7a). Excess of L"Mn-THF results in the formation of P-and ^-coordinated LnMn-P(Ph2)C(0)(^ 2 -C2H2Ph)MnL" (8a). In the presence of HP(0)Ph2, 4 a is oxidized with molecular oxygen to give the phosphorylated alcohol RC[P(0)Ph2]20H (9 a). Via the oxide 10 a and the enol ether Ph2(0)P-CHPh-CH = C(0CH3)P(0)Ph2 (11a) the ester Ph2(0)P-CHPh-CH = C[0C(0)R]P(0)Ph2 (12 a) can be isolated from the Arbusov reaction of 3 a and CH3OPPh2. 
  Reference    Z. Naturforsch. 38b, 726—732 (1983); eingegangen am 19. Januar 1983 
  Published    1983 
  Keywords    Unsaturated Acylphosphanes, Reactivity, Complex Chemical Behaviour 
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 TEI-XML for    default:Reihe_B/38/ZNB-1983-38b-0726.pdf 
 Identifier    ZNB-1983-38b-0726 
 Volume    38 
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