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Facet   section ZfN Section B:Volume 028  [X]
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1973 (192)
81Author    C. Von, S.Requires cookie*
 Title    Radical Chain Reactions in Crystalline oc-Lactose Monohydrate  
 Abstract    y-Radiolysis, carbohydrates, radical chain reactions, crystalline state, deoxy-lactobionic acids It has been known for some time th at in the y-radiolysis of some crystalline carbohydrates, e.g. a -D -g lu c o se 13 and a-lactose • H 20 2-4-5, acids are formed with high G-values*. From the magnitude of the G-values chain reactions are to be expected which largely seem to be restricted to the crystal­ line state1. P h i l l i p s and B a u g h 1 found for poly­ crystalline a -D -g lu c o se G(acid) = 13.2 whereas freeze-dried samples yield only (r(acid) = 4. Even more pronounced is this effect in a -la c t o s e • H 20 which gives G(acid) > 402> 4> 5 while in the dehy­ drated form acid is produced with G = 4.82. To elucidate the mechanism of such chain react­ ions we studied the y-radiolysis of crystalline a-lactose • H 20 . As major products were identified 5-deoxy-lactobionic acid (G = 40), 2-deoxy-lacto-bionic acid lactone (G = 20), and galactonic acid lactone (G = 4.5) as well as 4-deoxyglucose (G — 4.5) (dose < 4 • 1020 eV/g, dose rate 1.35 • 1018 eV /g • min). The products were identified by g.l.c. -m.s. after trimethylsilylation. The deoxy-lactobionic acids had to be hydrolized prior to this procedure. The structures were confirmed by re­ ducing the product with NaBD4 yielding deuterat-ed polyalcohols with interpretable mass spectra6«7. The above products point to the existence of three chain reactions in a-lactose • H 20 , their na­ ture being analogous or at least quite similar to th at in ethylene glycol8*12 (which even occurs in diluted aqueous solutions). This chain process is given by the Equs (l)-(3). 
  Reference    (Z. Naturforsch. 28b, 367—368 [1973]; received January 19 1973) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0367_n 
 Volume    28 
82Author    D.Requires cookie*
 Title    Studies in the Synthesis of Some 4-Hydroxy-3.5- Disubstituted l-p-Tosyl-2-pyrazolines  
 Abstract    u r g a N a t h D h a r and R a m e s h C. M u n j a l Hydroxypyrazolines, synthesis, spectroscopic studies E s c h e n m o s e r et al. la observed that alicyclic <x,ß-unsaturated carbonyl compounds can be readily con­ verted into acetyl enic ketones in accordance with the Sdieme lb 
  Reference    (Z. Naturforsch. 28b, 369—370 [1973]; received October 23 1972) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0369_n 
 Volume    28 
83Author    Requires cookie*
 Title     
 Abstract    o l f g a n g V o e l t e r , O s k a r O s t e r und E b e r h a r d B r e i t m a i e r l3C NMR spectroscopy, conformation, proline, peptides Die cis-trans-Isomerie von Prolinderivaten ist Ge­ genstand mehrerer theoretischer und experimenteller Arbeiten l. Zum experimentellen Nachweis der Ste­ reoisomeren werden besonders optische Rotationsdis­ persion 2, Circulardichroismus3 und Protonenreso­ nanz 2 verwendet. Im Gegensatz zur NH-Funktion von Aminosäuren kann die Iminogruppe im Prolin cis-und framständige Bindungen eingehen. Die genaue Kenntnis dieser cis-trans-Isomerie erleichtert daher die Aufklärung der Sekundärstruktur von Prolinpeptiden. Abb. 1 zeigt die Strukturen cis-und transisomerer Prolinpeptide. Im ds-Isomeren ist die Carbonylgruppe der Peptidbindung dem <5-Kohlenstoffatom des Pro­ linrestes räumlich näher als im trans-Isomeren. 
  Reference    (Z. Naturforsch. 28b, 370—373 [1973]; eingegangen am 26. 0ktober/20. Dezember 1972) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0370_n 
 Volume    28 
84Author    N. K.Requires cookie*
 Title    Mannich bases 4-hydroxy-coumarin N, Ar-Bis-(4-hydroxy-coumarin-3-yl-methyl)-aryla- mines, N , N , N ', ]V'-Tetra-(4-hydroxy-coumarin- 3-yl-methyl)-arylendiamines  
  Reference    (Z. Naturforsch. 28b, 373—374 [1973]; eingegangen am 30. Oktober 1972/4. Januar 1973) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0373_n 
 Volume    28 
85Author    R.Requires cookie*
 Title    Activation parameters in the Elucidation of Reaction Mechanism: Oxidation of Mandelic Acid by Lead Tetra-acetate  
 Abstract    S h a n k e r , S . K B a n e r j e e and 0 . P. S a c h d e o D epartm ent o f Chemistry, U niversity o f Udaipur, Kinetic isotope effect, mandelic acid, activation parameters Recent work on the decomposition of lead tetra-carboxylates in benzene has provided convincing evid­ ence for the mediation of free radicals1. It is also well known that bases like pyridine catalyse the oxid­ ation of alcohols, a-hydroxy acids and formic acid 2 by lead tetra-acetate, Pb(IV). Here it is assumed that role of pyridine in a non-polar solvent like benzene is one of diverting the homolytic path to that involving the heterolytic cleavage of the Pb-O bond3. Since hydroxy acids are reported to undergo C-C bond cleavage with Pb(IV) 4, it was considered fruitful to investigate the oxidation of mandelic acid in benzene and in benzene containing pyridine with particular reference to the evaluation of activation parameters in the two media. Since our findings were unusual, it prompted us to make a preliminary report on the reaction. Solvents and reagents used were purified and dried in a conventional manner. Pb(OAc)4, prepared by the method of B a i l a r 5 (purity 98% after recrystallisa­ tion twice from AcOH) was washed several times with 
  Reference    (Z. Naturforsch. 28b, 375—376 [1973]; received December 18 1972/January 7 1973) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0375_n 
 Volume    28 
86Author    Requires cookie*
 Title    ^ rR  
 Abstract    I.e. the chosen radical is allowed to react homogen­ eously with a standard reference substance and the products 1 and 2 measured, usually by gas diromato-graphy. The ratio 1/2 is then taken to be a measure of the polar nature of R" 9. We wish to point out the danger of interpreting such results solely on this basis. The basic error lies in the assumption that the reaction occurs in a single step 10. The role of cyclohexadienyl radicals in such reactions is now well documented 10 and hence it is more likely that 1 and 2 arise via reactions (2) and (3). + possibly dimeric products. R equest for reprints should be sen t to Dr. W . G. F i l b y , K em forschungszentrum Karlsruhe, In stitu t f. Radiochem ie, D-7500 Karlsruhe, P ostfach 3640. 
  Reference    (Z. Naturforsch. 28b, 377 [1973]) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0377_n 
 Volume    28 
87Author    Requires cookie*
 Title    Preparation of Pyridyl-(4)-diazomethane  
 Abstract    Pyridyl-(4)-diazomethane Unsere Arbeiten über Metallkomplexe mit polyme­ ren Liganden 1 lassen es uns recht sinnvoll erscheinen, auch Poly-bis-(4-pyridyl)äthylen als koordinierenden Liganden einzusetzen. Um die direkte Polymerisation von Bis-(4-pyridyl)-äthylen, die bis jetzt nur sehr un­ vollständig gelungen is t2— 3, zu umgehen, versuchen wir die Polymerisation von Pyridyl-(4)-diazomethan unter N 2-Eliminierung, die ein Polymeres gleicher Zusammensetzung entstehen lassen sollte. Dazu ist es allerdings nötig, das Diazomethan in sehr reiner Form vorliegen zu haben. Uber die Darstellung von Pyridyl-(4)-diazomethan wurde zwar schon berichtet 4, doch gelang dies nur in ätherischer Lösung. Wir erhielten nun die Diazover­ bindung erstmals in reiner, kristalliner Form. Frisch destillierter Pyridin-4-aldehyd wird unter Kühlung zu einer wäßrigen Hydrazinhydratlösung getropft. Nach Abziehen des Wassers am Dampfbad und anschließendem Destillieren des viscosen Rück­ standes am Hochvakuum erhält man das Isonicotin-hydrazon. Dieses wird nun in Chloroform mit aktivem Mangandioxid 5 unter Eiskühlung oxidiert. Nach vor­ sichtigem Abziehen des Chloroforms bei Raumtempe­ ratur wird der Rückstand im Vakuum fraktioniert. Bei 54 °C15mm erhält man in der Vorlage reines, kristallines Pyridyl-(4)-diazomethan in recht guten Ausbeuten. Oxidation und Aufarbeitung des Reaktionsgemi­ sches muß ohne Verzögerung nacheinander erfolgen, da sonst die Zersetzung des Diazomethans schnell fort­ schreitet. Der Gehalt des kristallinen Produktes an Diazome­ than konnte nach Zugabe von Essigsäure in Äther durch Rücktitration des Überschusses mit Natronlauge zu 100% bestimmt werden. Das reine, kristalline Dia­ zomethan ist im Tiefkühlschrank sehr beständig. Die langsame Zersetzung an Licht und bei Zimmertempe­ ratur liefert fast ausschließlich das entsprechende Alda­ zin. Das IR-Sepktrum des Pyridyl-(4)-diazomethans mit mit KBr zeigt, im Unterschied zu dem Lösungsspek­ trum in Äther4, bei 2066 cm-1 die vn2-Das 1H-KMR-Spektrum in Deuterochloroform weist bei 6,85 und 8,4 ppm rel. i. TMS die beiden Pyridinbanden 
  Reference    (Z. Naturforsch. 28b, 378 [1973]; eingegangen am 12. Januar 1973) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0378_n 
 Volume    28 
88Author    P., K. B., F. E.Requires cookie*
 Title    Anomale Temperaturabhängigkeil von 186Re, 187Re-Kernquadrupolspektren bei Perrhenaten* Anomalous Temperature Dependence of 185Re,187Re-NQR-Spectra of Perrhenates  
 Abstract    Rhenium, NQR-spectra, perrhenates 1S5Re,187Re-NQR-spectra of polycrystalline NH4Re04 and ND4Re04 show a strong temperature dependence of their transition frequencies with anomalous positive temper­ ature coefficients in contrast to the behaviour of other measured perrhenates. The positive values of the temperature coefficients are explained by an additional intermolecular interaction of the cations with R e04~, which strengthens the intramolecular mechanism of reducing jt-bond character with temperature. 
  Reference    (Z. Naturforsch. 28b, 379—382 [1973]; eingegangen am 28. März 1973) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0379 
 Volume    28 
89Author    H., P. F.Requires cookie*
 Title    Polarographische Untersuchungen an Metallkomplexen des Formylferrocenthiosemicarbazons Polarographie Investigations on Metal Complexes of Formylferrocenethiosemicarbazone  
 Abstract    The complexes ML2 (M = Co(II), Ni(II), Cu(II), Zn(II) and Cd(II), LH — formylferro-cenethiosemicarbazone) and Cu2L2 are described. Their IR-and UV-spectra and their polarographic behaviour are reported. 
  Reference    (Z. Naturforsch. 28b, 383—388 [1973]; eingegangen am S. April 1973) 
  Published    1973 
  Keywords    Formylferrocenethiosemicarbazone, metal complexes, IR-spectra, UV-spectra, polaro-graphic behaviour 
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 Identifier    ZNB-1973-28b-0383 
 Volume    28 
90Author    Requires cookie*
 Title    Über neuere Polym etallate Polyanions of Novel Structural Types  
 Abstract    Polymetallates, preparative methods, vibrational spectra By the application of newer preparative methods and specific organic cations single crystals of polymetallates were obtained of till now unknown structural types. These are salts with polyanions W ,0 192\ W 10O324*, [H W 120 38(0 H)2]5', Mo80 192' and HV40 123-, fur­ thermore £ara-tungstates A and B, as well as the compounds [N(CH)3)4] 2 Mo80 25-5H20 and [N(CHs)4]2Mo10 0 31 • 7H20 . The structures of the anions W80 192' and W10O324' were elucidated by X-R ay analyses; the structure of the Mo80 192' was derived by vibrational spectroscopy. The knowledge of newer polyanion structures increasingly enables us to gain an insight into the complicated mechanism metal salt solutions. 
  Reference    (Z. Naturforsch. 28b, 389—404 [1973]; eingegangen am 5. März 1973) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0389 
 Volume    28 
91Author    Requires cookie*
 Title    Synthesis o f Pure and Mixed Double Oxides with the Ilmenite Structure  
 Abstract    e l l in g s a n d G . M . H . v a n d e V e l d e 
  Reference    (Z. Naturforsch. 28b, 405 [1973]) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0405 
 Volume    28 
92Author    Requires cookie*
 Title    Uvanit m it organischen Zwischenschichtkationen und seine Intercalationskomplexe m it n-Alkylaminen und n-Alkanolen The Chemistry of Uranylvanadates with Trimetavanadate Ions and Layer Structure (Uvanite), II* Uvanite with Organic Interlayer Cations and its Intercalation Complexes with n-Alkylamines and rc-Alkanols  
 Abstract    K l a u s B e n e k e , U l r ic h G r o s s e -B r a u c k m a n n , G e r h a r d L a g a l y und A r m in W e i s s Uvanite, uranyltrim etavanadate, alkylamine complexes, alkanol complexes, intercalation compounds The interlayer cations of uvanite can be exchanged quantitatively by n-alkylammonium ions according to M+[U02V30 9] + CnH 2n+1N H ,+ C"H2n+1N H 3[U02V30 9] + M+. In the stoichiometric compounds the alkyl chains of the cations (« = 6-18) are poorly ordered in monolayers and oriented nearly perpendicular to the uranyltrim etavanadate layers though the space filling is unfavorable with this arrangement. During the cation exchange a t pH = 7-9 additional free amine molecules are taken up yielding 1:1 inter­ calation complexes (CnH 2"+1NH s) (CnH an+1NH2) [U 0 2V30 9] with close-packed, well ordered monolayers of alkyl compounds. W ith excess of pure amines or pure alkanols 1: 3 intercalation complexes (CnH 2n+1NH,) (CnH 2n+1NH2),[U 0 2V30 #] or (CnH 2n+1N H 3) (C"*H2n-+10 H)s[U 0 2V30 9] («,«' = 6-18] are formed w ith the alkyl chains ordered to bimolecular layers. These complexes rearrange at higher tem perature into new phases as a consequence of rotational isomerisation of the alkyl chains. 
  Reference    (Z. Naturforsch. 28b, 408—415 [1973]; eingegangen am 27. März 1973) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0408 
 Volume    28 
93Author    J.Requires cookie*
 Title    Orbitalreihenfolgen und Ladungsdichten in Methylthio-und Methoxyboranen* Photoelectronspectroscopic Investigations on Boron Compounds, I Orbitalsequences and Charge Densities of Methylthio- and Methoxyboranes  
 Abstract    ü r g e n K r o n e r , D i e t e r N ö l l e und H e i n r i c h N öth 
  Reference    (Z. Naturforsch. 28b, 416—125 [1973]; received 19. März 1973) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0416 
 Volume    28 
94Author    R. IcRequires cookie*
 Title    Die Kristallstruktur von Methylquecksilberazid The Crystal Structure of Methyl Mercury Azide  
  Reference    (Z. Naturforsch. 28b, 426—428 [1973]; eingegangen am 21. März 1973) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0426 
 Volume    28 
95Author    Requires cookie*
 Title    Polarographie Reduction o f Zinc and Thorium in Furfuryl Mercaptan Media  
  Reference    (Z. Naturforsch. 28b, 429 [1973]) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0429 
 Volume    28 
96Author    Requires cookie*
 Title    Zweikem ige Eisen-und Scandium-Porphine des Typs //-Oxo-bis[octaäthylporphinatometall(III)]  
  Reference    (Z. Naturforsch. 28b, 433 [1973]) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0433 
 Volume    28 
97Author    Requires cookie*
 Title    © L  
 Abstract    helatbildner der Pyridin-und Chino­ lin-Reihe können m it D iphenylborsäureanhydrid zu Borchelat-5-Ringen um gesetzt werden. Chelat-6-Ringe werden erhalten, wenn die iV-Oxide der en t­ sprechenden Chelatbildner eingesetzt w erden1. D er E in b au der iV-Oxid-Sauerstoffatome in die Che-latringe, d. h. die Ringerw eiterung zu Chelat-6-Rin-gen, konnte IR -spektroskopisch anhand der Valenz­ schwingung exocyclischer C = O-Gruppen nachge­ wiesen w erden: Die iV-Oxid-Chelate haben gegen­ über den vergleichbaren Chelat-5-Ringen erw ar­ tungsgem äß niedrigere W ellenzahlen der C = 0 -Va­ lenzschwingung1 . In der vorliegenden A rbeit werden die Massen­ spektren der borhaltigen Verbindungen 1-14 disku­ tiert. Den generellen C harakter der M assenspektren von F ünf-und Sechsringchelaten zeigen die Abbn. 1 und 2 m it den Spektren der V erbindungen 1 und 2. Neben dem Molekülion (M) erscheinen folgende F ragm entionen in teressant: Die A bspaltung von Sauerstoff (M-O), Kohlenm onoxid (M-CO), Kohlen­ 
  Reference    (Z. Naturforsch. 28b, 440 [1973]) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0440 
 Volume    28 
98Author    H. O.Requires cookie*
 Title    Neue Einlagerungsverbindungen von Kaolinit, Nakrit, Dickit, Halloysit und Titandisulfid mit Imidazol und Methylimidazol New Layer Intercalation Compounds of Kaolinite, Nacrite, Dickite, Halloysite and Titandisulfide with Imidazole and Methylimidazole  
 Abstract    A. W e i s s , R . R u t h a r d t T itan su lfid e, k a o lin ite , n a c rite , d ick ite, h allo y site 
  Reference    (Z. Naturforsch. 28b, 446—449 [1973]; eingegangen am 12. März 1973) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0446 
 Volume    28 
99Author    K.Requires cookie*
 Title    Kinetics and Mechanism o f the Oxidation of a-Hydroxy Carboxylic Acids by Bromine  
  Reference    (Z. Naturforsch. 28b, 450 [1973]) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0450 
 Volume    28 
100Author    Requires cookie*
 Title    Die gas -chromatographische Untersuchung von dimeren Pyrimidinen, XXIII * Investigation of Dimeric Pyrimidines by Gas Chromatography, X X III  
 Abstract    E g o n F a h r , R e i n h a r d P a s t i l l e und H a n s j ö r g Ma g e r l 
  Reference    (Z. Naturforsch. 28b, 454 [1973]) 
  Published    1973 
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 Identifier    ZNB-1973-28b-0454 
 Volume    28 
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