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1979 (5)
1978 (3)
1976 (2)
1Author    Thorsten Kemmer, Hans Brockmann, Nikolaus RischRequires cookie*
 Title    Die Einzelkomponenten der Bacteriophäophorbidmethylester von Bacteriochlorophyll c und d The Individual Components of Bacteriophaeophorbide Methyl Esters from Bacteriochlorophyll c and d  
 Abstract    The preparative column chromatographic separation on small grained silica gel of the bacteriophaeophorbide-c-and -d-methyl esters into their homologous and isomeric components is described. The influence of particular regions of the molecule, which carry different alkyl-substituents, on the chromatographic separability is selectively enhanced through the variation of the eluent. Mass and ifl NMR spectra of the pure components are discussed. Einführung Von den in Chlorobiaceae vorkommenden Bacterio-chlorophyllen c und d ist schon seit den Untersuchun-gen von Holt und Mitarbeitern [1, 2] bekannt, daß sie in der Natur als komplexe Gemische isomerer und homologer Verbindungen vorkommen. Eine Trennung in die einzelnen Komponenten ist für die aus den Chlorophyllen durch Hydrolyse leicht zu-gänglichen Phäophorbide durch Verteilen zwischen Ether und Salzsäure an Celite-Säulen beschrieben worden [3-5]. Wieweit dabei die einzelnen Kompo-CH3 nenten wirklich in reiner Form erhalten wurden, ist heute schwer zu überprüfen; bei den sich anschlie-ßenden physikalischen und chemischen Untersu-chungen wurden nämlich zum Teil widersprüchliche Resultate erhalten [6, 7]. Dennoch konnten Holt und Mitarbeiter [1, 2] aus ihren Untersuchungs-ergebnissen die Konstitutionsformeln 1 und 2 für die Bacteriochlorophylle c und d ableiten, die trotz zeitweiliger Kritik [7-9] durch neuere Arbeiten nur bestätigt wurden [10, 11]. Chlorobium-Bacteriochlorophylle cd) und d(2) 
  Reference    Z. Naturforsch. 34b, 633—637 (1979); eingegangen am 10. August 1978 
  Published    1979 
  Keywords    Chromatography, Separation, Bacteriochlorophylls, X H NMR 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0633.pdf 
 Identifier    ZNB-1979-34b-0633 
 Volume    34 
2Author    WolfgangA. Herrmann, Ilona SchweizerRequires cookie*
 Title    Übergangsmetall-Methylen-Komplexe, VI [1] Zur irreversiblen -Methylen/Carbonyl-Isomerie zweikerniger Cobalt-Komplexe mit bifunktionellen Methylen-Liganden Transition Metal Methylene Complexes, VI [1] On the Irreversible //-Methylene/Carbonyl Isomerization of Binuclear Cobalt Complexes with Bifunctional Methylene Ligands  
 Abstract    Ethyl diazoacetate (2 a) and £erZ-butyl diazoacetate (2 b) are converted into the metal stabilized, doubly bridging alkoxycarbonyl carbenes upon photolysis with (r? 5 -C5H5)Co(CO)2 (1) in tetrahydrofurane at —110°C. Although the yields of //-dicarbonyl-/(-ethoxy-carbonylmethylene-bis(?7 5 -cyclopentadienylcobalt) (3 a) and the corresponding ieri-butyl derivative (3b) are low, both compounds attract considerable attention due to an un-expected and hitherto unknown irreversible carbonyl bridge opening process with concomitant //-methylene rearrangement. These isomerizations have been established by IR and 1 H NMR methods to be first order intramolecular processes. 
  Reference    Z. Naturforsch. 33b, 1128—1135 (1978); eingegangen am 6. Juli 1978 
  Published    1978 
  Keywords    /<-Alkoxycarbonylmethylene, Terminal/Bridging Carbonyl Groups, Cobalt, IR, X H NMR 
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 TEI-XML for    default:Reihe_B/33/ZNB-1978-33b-1128.pdf 
 Identifier    ZNB-1978-33b-1128 
 Volume    33 
3Author    Henri Brunner, Manfred Muschiol, Wilfried NowakRequires cookie*
 Title    Optisch aktive Übergangsmetall-Komplexe, LVII [1]  
 Abstract    (+)-und (—)-C5H5M(CO)(P02R*)X mit M = Fe, "Fe und X = 1, COCH3, CH3 Optically Active Transition Metal Complexes, LVII [1] (+)-and (—)-C5H5M(CO)(P02R*)X with M = Fe, "Fe, and X = I, COCH3, CH3 In the reaction of C5H5Fe(CO)2l and CsHsFefCO^CHa, respectively, with S-(+)-(C6H5)2PN(CH3)CH(CH3)(C6H5) (abbreviated P02R*) the complexes C5H5Fe(CO)(P02R*)I(l),C5H5Fe(CO)(P02R*)COCH3(2),andC5H5Fe(CO)(P02R !,t)CH3(3) are formed as pairs of diastereoisomers the components of which differ only in the configu-ration at the iron atom. CsH5Fe(CO)(P02R*)CH3 (3) can be obtained in higher yield by photochemical decarbonylation of C5H5Fe(CO)(P02R*)COCH3 (2). The (+)s85-and (—)365-diastereoisomers of each pair exhibit different chemical shifts in the X H NMR spectra. Diastereoisomer separation can be achieved by fractional crystallization. Starting with 57 Fe metal (—)365-C5H5 57 Fe(CO)(P02R*)I was prepared via 57 FeI2, 57 Fe(CO)4l2, C5H5 57 Fe(CO)2l, and C5H5 57 Fe(CO)(P02R*)I in order to demonstrate optical activity of a 57 Fe compound in the y region by Mössbauer polarimetry in later experiments to be reported elsewhere. 
  Reference    Z. Naturforsch. 33b, 407—411 (1978); eingegangen am 24. Januar 1978 
  Published    1978 
  Keywords    Diastereoisomer Separation, X H NMR, Optical Activity, Transition Metal Complexes 
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 TEI-XML for    default:Reihe_B/33/ZNB-1978-33b-0407.pdf 
 Identifier    ZNB-1978-33b-0407 
 Volume    33 
4Author    Werner WinterRequires cookie*
 Title    Isomerisierung von Pd-0=PR3 -koordiniertem 0,0' -Bis(phenyläthinyl) -triphenylphosphinoxid Isomerization of Pd-0 = PR3 Coordinated o,o'-Bis(phenyläthinyl)-triphenylphosphineoxide  
 Abstract    o,o'-Bis(phenylethynyl)-triphenylphosphineoxide, coordinated to Pd(II) with the P = 0-group, is isomerized in boiling xylene to the condensed phosphepin-and dihydrophos-phocin oxides (4) and (6). The structure of 6 is determined by catalytic hydrogenation, iH NMR and confirmed by an X-ray analysis, currently carried out. The hydrogenated products 7 A and 7B are conformational isomers. The kinetic data of the ring inversion 7 A ^ 7B are determined. o,o'-Bis(phenyläthinyl)-triphenylphosphinoxid(l) kann mit Tolan und Pd(C6H5CN)2Cl2 in Tribenzo-phosphepinoxide überführt werden (Pd(II)-kataly-sierte Acetylentrimerisierung) 1 . Bei dieser Reaktion bildet sich zuerst der Pd-Phosphinoxid-Komplex (2), der auch in quant. Ausbeute durch Umsetzung von 1 mit Pd(C6H5CN) 2 Cl2 (im Molverhältnis 1:2) in Benzol bei Raumtemperatur dargestellt werden kann 1 . Beim mehrstündigen Erhitzen dieses Kom-plexes in siedendem Xylol entstehen 2 neue Isomere von 1: die dunkelblaue Verbindung 4 und die orange Verbindung 5 oder 6. Anhaltspunkte über die Struk-turen von 4 und 5 oder 6 ergeben sich aus den Massenspektren, den IR-Spektren (P=0-Schwin-gung bei 1190 cm -1 , Fehlen der C = C-Streckschwin-gungsbande bei ca. 2200 cm -1) und den Elektronen-spektren: So zeigt 4 für Azulene typische Absorp-tionsbanden bei 725 (sh), 655 und 612 m/u (log 
  Reference    (Z. Naturforsch. 31b, 1116—1121 [1976]; eingegangen am 8. April 1976) 
  Published    1976 
  Keywords    Palladium-Phosphinoxide Complex, Phosphepin-oxides, Phosphocin-oxides, Conformational Stability, X H NMR 
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 TEI-XML for    default:Reihe_B/31/ZNB-1976-31b-1116.pdf 
 Identifier    ZNB-1976-31b-1116 
 Volume    31 
5Author    Alfred Schmidpeter, Klaus Blanck, Johann HögelRequires cookie*
 Title    Bis [cyclotri(phosphazen)yl] oxide 1 Bis[cyclotri(phosphazen)yl]oxides  
 Abstract    Hydrido-cyclotri(phosphazen)es can be coupled by one or two step oxidation to give symmetric and unsymmetric bis[cyclotri(phosphazen)yl]oxides. Their structure follows from the analysis of their NMR spectra. 
  Reference    (Z. Naturforsch. 31b, 1466—1467 [1976]; eingegangen am 16. Juli 1976) 
  Published    1976 
  Keywords    Hydrido-cyclophosphazenes, Halogenation, X H NMR, 31 P NMR, Complex Spin Systems 
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 TEI-XML for    default:Reihe_B/31/ZNB-1976-31b-1466.pdf 
 Identifier    ZNB-1976-31b-1466 
 Volume    31 
6Author    Hubert Schmidbaur, Peter HollRequires cookie*
 Title    l.l-Dimethyl-l-methoxy-l/ 5 phospholan und -phosphorinan: Synthese, Struktur und dynamisches Verhalten 1,1 -Dimethyl-1-methoxy-lA 5 phospholane and -phosphorinane: Synthesis, Structure and Dynamic Behaviour  
  Reference    Z. Naturforsch. 33b, 489—492 (1978); eingegangen am 28. Februar 1978 
  Published    1978 
  Keywords    Alkoxy-dialkyl-phospholanes, Intermolecular Ligand Exchange, 13 C NMR, X H NMR, 31 P NMR 
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 TEI-XML for    default:Reihe_B/33/ZNB-1978-33b-0489.pdf 
 Identifier    ZNB-1978-33b-0489 
 Volume    33 
7Author    Kenji Nomiya, Nahoko Wako, Tomoko Komiyama, Makoto MiwaRequires cookie*
 Title    Catalytic Oxygenation of 3-Methylindole by Co(II)-Schiff Base Planar Complexes  
  Reference    Z. Naturforsch. 34b, 442—447 (1979); received November 13 1978 
  Published    1979 
  Keywords    Catalytic Oxygenation, 3-Methylindole, N, N'-Ethylenebis(acetylacetoniminato)Co(II), Manometric Observation, X H NMR 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0442.pdf 
 Identifier    ZNB-1979-34b-0442 
 Volume    34 
8Author    Jochen Ellermann, Martin Lietz, Peter Merbach, Gerhard Thiele, Gerd ZoubekRequires cookie*
 Title    Chemie polyfunktioneller Liganden, 53 [1] Über methyl-substituierte Triarsa-trioxa-, Triarsa-trithia- und Triarsa-triaza-adamantane und über den stark aufgeweiteten Adamantan-Käfig im Schwefel-Derivat Chemistry of Polyfunctional Ligands, 53 [1] About Methyl-substituted Triarsa-trioxa-, Triarsa-trithia-and Triarsa-triaza-adamantanes and about the Strongly Spread Adamantane Cage in the Sulfur Derivative  
 Abstract    The reaction of l,l,l-tris(diiodarsinomethyl)ethane, CH3C(CH2Asl2)3 (1), with H2O, H2S and CH3NH2 in THF gives the adamantane cage compounds CH3C(CH2ASO)3 (4), CH3C(CH2ASS)3 (5) and CH3C(CH2ASNCH3)3 (6) in high yields. The crystal structure of 5 has been determinated by X-ray diffraction. The unit cell (space group P2i/w) contains 4 isolated molecules in a cubic closest packing. The heteroadamantane 5 has an enlarged cage structure with extremely spread C-C(H2)-As bond angles of 124° at the methylene carbon atoms. Some pharmacological properties of the adamantane derivatives 4 and 5 have been studied. All compounds have been characterized by mass spectrometry and infrared, Raman and X H NMR spectroscopy. 
  Reference    Z. Naturforsch. 34b, 975—982 (1979); eingegangen am 26. März 1979 
  Published    1979 
  Keywords    Heteroadamantanes, Vibrational Spectra, Mass Spectra, X H NMR, Molecular and Crystal Structure 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0975.pdf 
 Identifier    ZNB-1979-34b-0975 
 Volume    34 
9Author    Heinz Falk, Klaus ThirringRequires cookie*
 Title    On the Chemistry of Pyrrole Pigments, XXXIV [1] On the Configurations and Conformations of Diastereomeric N-Methyl-O-methyl-bilatrienes-abc  
 Abstract    of the aetiobiliverdin-IV-y-lactimether yields a lactam-N-methylated derivative the structure of which was proven by an ether cleavage and iH NMR spectro-scopy. The configuration (Z,Z,Z) was deduced from iHNMR experiments. Photo-isomerization exclusively forms the (E,Z,Z) diastereomer. By conformational analysis using the LIS technique and correlations of UV-VIS spectra and PPP-type calculations a more or less helical arrangement for the two diastereomers was confirmed. The twisting is maximal at the methine single bond adjacent to the site of N-methylation, the overall geometry seems to be much more distorted than the non methylated derivatives. 
  Reference    Z. Naturforsch. 34b, 1600—1605 (1979); eingegangen am 13. Juli 1979 
  Published    1979 
  Keywords    X H NMR, UV-VIS, Lanthanide Ion Induced Shifts, PPP-Calculations, Conformational Analysis Methylation 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-1600.pdf 
 Identifier    ZNB-1979-34b-1600 
 Volume    34 
10Author    MohamedHilmy Elnagdi, Mohamed Ezzat, KamalUsef Kandeel, SadekRequires cookie*
 Title    Reactions with Cyclic Amidenes III: Synthesis of Some New Fused Pyrazole Derivatives  
  Reference    Z. Naturforsch. 34b, 275—279 (1979); received August 28 1978 
  Published    1979 
  Keywords    Diazobetaienes, Dipolarcycloaddition, Pryazolo[4, 3-c]-l, 2, 3, 4-tetrazines, Ethoxycarbonyl Isothiocyanate, X H NMR 
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 TEI-XML for    default:Reihe_B/34/ZNB-1979-34b-0275.pdf 
 Identifier    ZNB-1979-34b-0275 
 Volume    34