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  • Inorganic Chemistry  (3)
  • AA'X spin system  (1)
  • Strong coupling effectsin 2D NMR  (1)
  • Vicinal P-P and P-C coupling constants  (1)
  • 1990-1994  (5)
  • 1
    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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  • 2
    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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  • 3
    Electronic Resource
    Electronic Resource
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 28 (1990), S. 500-504 
    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: 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.
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  • 5
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 607 (1992), S. 161-163 
    ISSN: 0044-2313
    Keywords: Organylfluorophosphanes ; reaction mechanism ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Dimerization of Di(n-butyl)fluorophosphane and its Reaction with BenzaldehydeThe phosphorus atom of organylfluorophosphanes possesses electrophilic as well as nucleophilic properties. This dualistic character decisively determines both their disproportionation and their reaction with aldehydes. The phoshanylphoshorane n-Bu2P—PF2(n-Bu)2, 1 b, has been proved to be the intermediat product of the disproportionation of n-Bu2PF. In the presence of an equimolar amount of Et3N an equilibrium exists between 1 b and the monomeric n-Bu2PF. n-Bu2PF react with benzaldehyde forming the phosphinitophoshorane n-Bu2P′—O—CHPh—PF2(n-Bu)2, 3 a. Reliable information on the reaction pathway has been obtained by means of crossing experiments.
    Notes: In Organylfluorphosphanen besitzt das Phosphoratom sowohl elektrophile als auch nucleophile Eigenschaften. Dieser dualistische Charakter ist für die Disproportionierung von Diorganylfluorphosphanen, R2PF, und für ihre Reaktion mit Aldehyden von entscheidender Bedeutung. Bei der Disproportionierung von n-Bu2PF tritt das Phosphanylphosphoran n-Bu2P—PF2(n-Bu)2, 1b, als Zwischenprodukt auf. In Gegenwart von äquimolaren Mengen Et3N steht 1 b mit dem monomeren n-Bu2PF im Gleichgewicht. n-Bu2PF reagiert mit Benzaldehyd zum Phosphinitophosphoran n-Bu2P′—O—CHPh—PF2(n-Bu)2, 3 a, dessen Bildungsweg durch „Kreuzungsexperimente“ eindeutig ermittelt werden konnte.
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