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  • 1
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Journal of Fluorine Chemistry 38 (1988), S. 335-340 
    ISSN: 0022-1139
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0749-1581
    Keywords: AA'X spin system ; P—C shift correlation ; Strong coupling effectsin 2D NMR ; P—P and P—C coupling constants ; Relative signs ; Diphosphonates ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The indirect determination of P—P coupling constants and their relative signs in some symmetrical diphosphonates by 31P—13C 2D NMR is introduced. Advantages and disadvantages of this method and others for the determination of the coupling constants of chemically equivalent nuclei are discussed. Strong coupling effects are analysed by means of simulated 2D spectra and the product operator formalism.
    Additional Material: 5 Ill.
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  • 3
    ISSN: 0749-1581
    Keywords: Diphosphonates ; Vicinal P-P and P-C coupling constants ; Karplus relationship ; Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Several α,β-diphosphonates with a norbornane or cyclohexane skeleton were prepared, and the 31P-31P coupling constants over three bonds for the ethyl or methyl esters, the acid and anion were obtained from the 13C NMR spectra or the 13C satellites in the 31P NMR spectra. The 3J(PP) values cover a range of about 90 Hz and are therefore well suited for conformational and configurational analysis. The dependence of 3J(PP) on the dihedral angle is well reflected by an extended Karplus relationship: 3J(PP) = A + B cos ϕ + C cos 2ϕ + D cos 3ϕ, with different parameters for the esters, acids and anions. For trans and gauche arrangements of the α,β-diphosphonic acids the dependence of the P-P coupling constants on the degree of titration is given. Investigations of the dependence of 3J(PC) on the PCCC dihedral angle show that a good curve fitting is achieved using the Karplus relationship 3J(PC) = AA + AB cos ϕ + C cos 2ϕ. A comparison of these curves with published data indicates smaller coupling constants for ϕ ≈ 0°. The coefficients of the Karplus equation for the 3J(PC) values obtained for esters are similar for acids and anions.
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  • 4
    ISSN: 0021-8383
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N.M.R. Investigation of 2,4-Bis(3,5-di-tert.-butyl-4-hydroxyphenyl)-2,4-dithioxo-1,3,2λ5,4λ5-dithiadiphosphetane and Selected Alcoholysis Products
    Additional Material: 4 Tab.
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  • 5
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Phosphinophosphite - a Hydrolysis Product of ‘Phosphorous Suboxide, P4O’The hydrolytic degradation of polymer phosphorus suboxide, ‘P4O’ and of the P4-molecule in aqueous ethanolic sodium hydroxide leads in addition to wellknown substances to a compound containing two phosphorus atoms directly attached. By 31P-NMR spectroscopy it was identified as phosphinophosphite, [OP(O)(H)—PH2]-.
    Notes: Beim hydrolytischen Abbau des polymeren Phosphorsuboxids „P4O“ wie auch des P4-Moleküls in wäßrig-ethanolischer Natronlauge wird neben bereits bekannten Spezies eine zweikernige Phosphorverbindung gefunden, die mit Hilfe der 31P-NMR-Spektroskopie als Phosphinophosphit, [OP(O)(H)—PH2]-, identifiziert wurde.
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  • 6
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, Properties and N.M.R. Spectroscopic Studies of 2,4-Dithioxo-2,4-dimercapto-1,3-diaza-2λ5,4λ5-diphosphetidinesOn the reaction of py · PS2Cl (1) or py · PS2F (2) (py = Pyridine) with hexamethyl disilazane in a molar ratio of 1:1 the pyridinium salt of the 1,3-bis(trimethylsilyl)-2,4-dimercapto-2,4-dithioxo-1,3-diaza-2λ5, 4λ5-diphosphetidine (3) is formed. 3 reacts with MeI to the corresponding methyl ester 9. There exist two isomers of 9, probable with cis and trans configuration of the MeS groups, respectively. 3 and 9 have been characterized by i.r., Raman, mass, and NMR spectroscopy. 4 reacts in acetonitrilic solution in the presence of water under hydrolytic cleavage of the trimethyl silyl groups whereas the P2N2 ring is preserved. The hydrolysis of 9 has been studied by 1H-, 31P-, and 13C-NMR spectroscopy.
    Notes: Bei der Reaktion der Dithiophosphorsäurebetaine Py · PS2Cl (1) und Py · PS2F (2) (Py = Pyridin) mit Hexamethyldisilazan im Molverhältnis 1:1 entsteht das Pyridiniumsalz des 1,3-Bis(trimethylsilyl)-2,4-dimercapto-2,4-dithioxo-1,3-diaza-2λ5, 4λ5-diphosphetidins (3), das mit Methyliodid zum entsprechenden Dimethylester (9) reagiert. 9 bildet zwei Isomere, die sich wahrscheinlich durch cis- und trans-Anordnung der MeS-Gruppen unterscheiden. 3 und 9 wurden IR-, Raman-, massen- und NMR-spektroskopisch charakterisiert. 4 reagiert in Acetonitril-Lösung in Gegenwart von Wasser unter hydrolytischer Abspaltung der Trimethylsilylgruppen und Erhalt des P2N2-Ringes. Der Verlauf der Hydrolyse wurde mittels 1H-, 31P- und 13C-NMR-Spektroskopie untersucht.
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  • 7
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, Properties, and N.M.R. Investigation of Phenylphosphonothioic Acid Bis-(trimethylsilylamide) and 1,3-Bis(trimethylsilyl)-2,4-diphenyl-2,4-dithioxo-1,3,2λ5,4λ5-diazadiphosphetidineThe reaction of phenylphosphonothioic dichloride PhP(S)Cl2 (1) with hexamethyl-disilazane (HMDSA) yields N,N′-bis(trimethylsilylamide) of phenylphosphonothioic acid PhP(S)(NHSiMe3)2 (2). The thermolysis of 2 leads to the 1,3-bis(trimethylsilyl)-2,4-diphenyl-2,4-dithioxo-1,3,2λ5, 4λ5-diazadiphosphetidine [PhP(S)NSiMe3]2 (3). The structures of the compounds 2 and trans-3 isolated in high purity habe been elucidated by means of mass, IR-, Raman-, and NMR (1H, 31P, 13C, 29Si) spectra. The first hydrolysis products of both compounds have been proved by NMR spectroscopy. Besides the predominantly formed trans-isomer of 3 the corresponding cis-isomer is obtained with 10% yield.
    Notes: Durch Umsetzung von Phenylthiophosphonsäuredichlorid PhP(S)Cl2 (1) mit Hexamethyldisilazan (HMDSA) wurde das Bis(trimethylsilylamid) dieser Säure PhP(S)(NHSiMe3)2 (2) hergestellt und durch thermische Zersetzung von 2 das 1,3-Bis(trimethyl-silyl)-2,4-diphenyl-2,4-dithioxo-1,3,2λ5,4λ5-diazadiphosphetid [PhP(S)NSiMe3]2 (3) erhalten. Mit Hilfe von Massen-, IR-, Raman- und NMR (1H, 31P, 13C, 29Si)-Spektren wurde die Struktur der in hoher Reinheit isolierten Verbindungen 2 und trans-3 aufgeklärt. NMR-spektroskopisch konnten die ersten Hydrolysestufen beider Verbindungen nachgewiesen werden. Neben dem vorwiegend entstehenden trans-Isomer von 3 wird zu etwa 10% das cis-Isomer gebildet.
    Additional Material: 5 Ill.
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  • 8
    ISSN: 0044-2313
    Keywords: Organylphosphine monosulfides ; organylphosphine monoselenides ; (1-hydroxyalkyl)-organyl-phosphine sulfides ; (1-hydroxyalkyl)-organyl-phosphine selenides ; bis(1-hydroxy-alkyl)-organyl-phosphine sulfides ; (1-hydroxy-1-methyl-ethyl)-phenyl-phosphine sulfide ; crystal structure ; hydrogen bonds ; 31P CP/MAS NMR ; quantumchemical calculation ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Investigation into Sulfides and Selenides of Primary Phosphines  -  The (1-Hydroxyalkyl)-organyl-phosphine Sulfides and Selenides, New Classes of CompoundsPrimary phosphines react with S8 and Se8, respectively, forming organylphosphine monosulfides, and monoselenides, respectively, RP(X)H2 (X = S, Se) which are well characterized by 31P NMR spectroscopy. Organylphosphine monosulfides are detected in the reaction mixture of primary phosphines with 2,4-diaryl-1,3,2,4-dithiadiphosphetane-2,4-disulfides, too. The reaction of primary phosphines with sulfur or selenium proceeds in presence of most of the ketones without formation of any side product. The (1-hydroxyalkyl)-organyl-phosphine sulfides and selenides, respectively, RP(X)(H)C(OH)R1R2, are yielded generally in crystalline form. The X-ray crystal structure analysis of the (1-hydroxy-1-methyl-ethyl)-phenyl-phosphane sulfide (R = Ph, R1 = R2 = Me) has shown that in the crystal the molecules are chained via intermolecular O—H … S hydrogen bridging bonds (O … S = 328 pm). Aldehydes react with primary phosphines and sulfur forming bis(1-hydroxyalkyl)-phenyl-phosphine sulfides, RP(S)[CH(OH)R1]2. 1H, 13C, and 31P NMR spectroscopic investigations allow to detect and to identify stereoisomers in some cases. Quantumchemical calculations reflect correctly which of the carbonyl compounds are able to react with the organylphosphine monosulfide formed as intermediate.
    Notes: Primäre Phosphane reagieren mit S8 oder Se8 und bilden neben einer großen Anzahl von Nebenprodukten Organylphosphanmonosulfide bzw. -selenide, RP(X)H2 (X = S, Se), die 31P-NMR- spektroskopisch charakterisiert werden können. Die Bildung von Organylphosphanmonosulfiden ist auch bei der Umsetzung primärer Phosphane mit 2,4-Diaryl-1,3,2,4-dithiadiphosphetan-2,4-disulfid nachweisbar. Praktisch ohne Nebenprodukte verläuft die Reaktion primärer Phosphane mit Schwefel oder Selen und einer Reihe von Ketonen. Es entstehen die meist kristallinen (1-Hydroxyalkyl)-organyl-phosphansulfide bzw. -selenide, RP(X)(H)C(OH)R1R2. Die Röntgen-Kristallstrukturanalyse des (1-Hydroxy-1-methyl-ethyl)-phenyl-phosphansulfids (R = Ph, R1 = R2 = Me) ergab, daß im Kristall intermolekulare O—H … S-Wasserstoffbrückenbindungen (O … S = 328 pm) zu einer kettenförmigen Anordnung der Moleküle führen. Aldehyde reagieren mit Phenylphosphan und Schwefel zu Bis(1-hydroxyalkyl)-phenyl-phosphansulfiden, C6H5P(S)[CH(OH)R1]2. 1H—, 13C— und 31P-NMR-Untersuchungen gestatten den Nachweis und die Zuordnung von auftretenden Stereoisomeren. Quantenchemische Berechnungen spiegeln richtig wider, welche Carbonylverbindungen in der Lage sind, mit dem intermediär gebildeten Phosphansulfid zu reagieren und welche nicht.
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  • 9
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: About the pH-Dependence of 31P and 13C NMR Spectra of Cyclohexane-, Cyclohexene-, and Benzenephosphonic Acids31P and 13C chemical shifts as well as P—C coupling constants of phosphonic acids are affected by the pH of the investigated solutions. This dependence was measured for aqueous solutions of cyclohexane-, cyclohex-1-ene-, cyclohex-2-ene-, cyclohex-3-ene-, and benzenephosphonic acid. It is shown that the 31P chemical shift and various 13C chemical shifts are well suited for the determination of pKa values.
    Notes: 31P- und 13C-chemische Verschiebungen wie auch P—C-Kopplungskonstanten von Phosphonsäuren werden entscheidend vom pH-Wert der untersuchten Lösungen beeinflußt. Für Cyclohexan-, Cyclohex-1-en-, Cyclohex-2-en-, Cyclohex-3-en- und Benzenphosphonsäure wurde die pH-Abhängigkeit von δP, δC und JPC ermittelt. An Hand von Beispielen wird gezeigt, daß sich die 31P-chemische Verschiebung und ausgewählte 13C-chemische Verschiebungen gut zur Bestimmung von pKS-Werten eignen.
    Additional Material: 2 Ill.
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  • 10
    ISSN: 0044-2313
    Keywords: Diphenoxyphosphorylchloride ; N′,N′-dialkyl-N-diphenoxyphosphoryl urea ; N-diphenoxyphosphoryl-N″,N″-dipropyl biuret ; X-ray crystal structure analysis ; n.m.r. spectra ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Reaction of Diphenoxyphosphorylchloride with N,N-disubstituted Ureas - Formation of Phosphorylated Biuret CompoundsN′,N′-disubstituted N-diphenoxyphosphorylureas, (PhO)2P(O)—NH—CO—NR1R2 (R1 = R2 = Et, 1; n-Pr, 2; n-Bu, 3; i-Bu, 4; R1 = Me and R2 = Ph, 5) as well as phosphorylated biuret compounds, (PhO)2P(O)—NH—CO—NH—CO—NR1R2 are obtained in the reaction of diphenoxyphosphorylchloride with N,N-disubstituted ureas and triethylamine. The biuret derivatives are formed via (PhO)2P(O)NCO. Their yield rises if the reaction is carried out without amine. The X-ray crystal structure analysis of (PhO)2P(O)—NH—CO—NH—CO—NPr2, 8, shows that dimers exist in the crystal with intermolecular as well as intramolecular hydrogen bonds. The framework formed by atoms P—N1—C1(O4)—N2—C2(O5)—N3(C3)C6 is planar. The existence of a rotation barrier along the bond C2-N3 was detected by NMR spectroscopy.
    Notes: Bei der Umsetzung von Diphenoxyphosphorylchlorid mit N,N-disubstituierten Harnstoffen in Gegenwart von Triethylamin treten neben N′,N′-disubstituierten N-Diphenoxyphosphorylharnstoffen, (PhO)2P(O)—NH—CO—NR1R2 (R1 = R2 = Et, 1; n-Pr, 2; n-Bu, 3; i-Bu, 4; R1 = Me u. R2 = Ph, 5), immer auch N″,N″-disubstituierte N-Diphenoxyphosphorylbiuret-Verbindungen, (PhO)2P(O)—NH—CO—NH—CO—NR1R2 auf. Sie entstehen über intermediär gebildetes (PhO)2P(O)NCO. Die Ausbeute an Biuretderivaten steigt, wenn ohne Aminzusatz gearbeitet wird. Die Röntgen-Kristallstrukturanalyse von (PhO)2P(O)—NH—CO—NH—CO—NPr2, 8, zeigt, daß im Kristall Dimere mit sowohl inter- als auch intramolekularen Wasserstoffbrücken vorliegen. Das Gerüst von 8 mit der Atomfolge P—N1—C1(O4)—N2—C2(O5)—N3(C3)C6 ist nahezu planar. NMR-Untersuchungen beweisen die Existenz einer Rotationsbarriere um die Bindung C2-N3.
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