Beiträge zur Chemie des Phosphors, 147 [1] 31P-Kernresonanzspektrum und Struktur von Hexaethyl-octaphosphan(6), P8Et6 / Contributions to the Chemistry of Phosphorus, 147 [1] 31P NMR Spectrum and Structure of Hexaethyloctaphosphane(6), P8Et6

1984 ◽  
Vol 39 (12) ◽  
pp. 1671-1675 ◽  
Author(s):  
Marianne Bäudler ◽  
Eberhard Därr ◽  
Gerhard Binsch ◽  
David S. Stephenson
Keyword(s):  
31P Nmr ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Complete Analysis ◽  
Nmr Spectrum ◽  
H Nmr ◽  
Configuration And Conformation

Hexaethyloctaphosphane(6) (1) was proven to possess the structure of a 2,3,4,6,7,8-hexaethylbicyclo[3.3.0]octaphosphane by a complete analysis of its 31P {1H } NMR spectrum. The chemical shifts and coupling constants yielded inform ation about the configuration and conformation of 1.

scholarly journals Beiträge zur Chemie des Phosphors, 132 [1]. 31P-Kernresonanzspektrum und Struktur von Trimethylheptaphosphan(3), P7Me3 / Contributions to the Chemistry of Phosphorus, 132 [1]. 31P NMR Spectrum and Structure of Trimethylheptaphosphane(3), P7Me3

1983 ◽  
Vol 38 (8) ◽  
pp. 955-960 ◽  
Author(s):  
Marianne Bäudler ◽  
Thomas Pontzen
Keyword(s):  
31P Nmr ◽  
Chemical Shifts ◽  
Experimental Spectrum ◽  
Complete Analysis ◽  
Methyl Groups ◽  
Nmr Spectrum ◽  
H Nmr

Trimethylheptaphosphane(3) (1) was proved to possess the earlier reported structure of a 3,5,7-triorganotrieyclo[2.2.1.02,6] heptaphosphane [3] by complete analysis of its 31P{1H} NMR spectrum. The experimental spectrum can be simulated very satisfactorily by the superposition of the spectra of two isomers P7Me3sym and P7Me3 asym, differing from each other in the orientation of the methyl groups. A comparison of the chemical shifts with those of (Me3Si)3P7 and Li3P7 leads to a detailed information about the geometry of the P7-skeleton in both isomers of 1.

21,22-Disubstituted 18α,19βH-Ursane Derivatives with Oxabicyclooctane System in Ring E

1993 ◽  
Vol 58 (1) ◽  
pp. 173-190 ◽  
Author(s):  
Eva Klinotová ◽  
Jiří Klinot ◽  
Václav Křeček ◽  
Miloš Buděšínský ◽  
Bohumil Máca
Keyword(s):  
Spectral Data ◽  
Spin Systems ◽  
Coupling Constants ◽  
Complete Analysis ◽  
Nmr Spectrum ◽  
Proton Proton ◽  
H Nmr ◽  
Proton Coupling ◽  
C Nmr

Reaction of 3β-acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (IIIa) and 20β,28-epoxy-21,22-dioxo-19α,19βH-ursan-3β-yl acetate (IIIb) with diazomethane afforded derivatives XII-XIV with spiroepoxide group in position 21 or 22, which were further converted into hydroxy derivatives XV and XVII. Ethylene ketals VIII-X were also prepared. In connection with the determination of position and configuration of the functional groups at C(21) and C(22), the 1H and 13C NMR spectral data of the prepared compounds are discussed. Complete analysis of two four-spin systems in the 1H NMR spectrum of bisethylenedioxy derivative Xb led to the proton-proton coupling constants from which the structure with two 1,4-dioxane rings condensed with ring E, and their conformation, was derived.

scholarly journals Beiträge zur Chemie des Phosphors, 96 [1] Darstellung und 31P-Kernresonanzspektrum von isotopen-substituiertem Trilithium-heptaphosphid, 6Li3P7 / Contributions to the Chemistry of Phosphorus, 96 [1] Preparation and 31P NMR Spectrum of Isotopicly Substituted Trilithiumheptaphosphide, 6Li3P7

1980 ◽  
Vol 35 (5) ◽  
pp. 517-521 ◽  
Author(s):  
Marianne Baudler ◽  
Thomas Pontzen ◽  
Josef Hahn ◽  
Hans Ternberger ◽  
Wolfgang Faber
Keyword(s):  
Room Temperature ◽  
31P Nmr ◽  
Chemical Shifts ◽  
Exchange Process ◽  
Complete Analysis ◽  
Ionic Character ◽  
Line Broadening ◽  
Threefold Axis ◽  
Nmr Spectrum ◽  
Li Isotope

Abstract The P7-skeleton of trilithiumheptaphosphide, Li3P7 (1), was proved to possess the earlier reported tricyclic structure [2] by complete analysis of the 31P NMR spectrum of 6Li3P7 observed at - 60 °C. The 6Li isotopic substitution was carried out to avoid the line broadening caused by the large quadrupole moment of the 7Li isotope. The unambiguous elucidation of the Li3P7 structure confirmed that the exchange process which causes all P atoms to become equivalent above room temperature is analogous to that in bullvalene. A comparison of the chemical shifts with those of (Me3Si)3P7 leads to the result that the P7-skeleton in Li3P7 is noticeably compressed along its threefold axis, thus indicating a predominant ionic character.

Beiträge zur Chemie des Phosphors, 116 Kernresonanzspektren und Kristallstruktur von Tri-tert-butylcyclotriphosphan / Contributions to the Chemistry of Phosphorus, 116 NMR Spectra and Crystal Structure of Tri-tert-butylcyclotriphosphane

1982 ◽  
Vol 37 (7) ◽  
pp. 797-805 ◽  
Author(s):  
Josef Hahn ◽  
Marianne Baudler ◽  
Carl Krüger ◽  
Yi-Hung Tsay
Keyword(s):  
Nmr Spectra ◽  
Chemical Shifts ◽  
Ring Structure ◽  
Coupling Constants ◽  
Complete Analysis ◽  
X Ray ◽  
Bond Angles ◽  
Tert Butyl ◽  
H Nmr ◽  
In Cis

A complete analysis of the 31P, 13C and 1H NMR spectra of tri-tert-butyl-cyclotriphosphane (1) was carried out and the resulting NMR parameters were correlated with the X-ray data of the molecule. It was found, that increasing P-P-C-bond angles correspond to a downfield shift and an increase of the absolute values of the negative 1J(PP) and 1J(PC) coupling constants. Generally, the chemical shifts of cyclotriphosphanes as well as of larger cyclic phosphanes depend on the endo- and exocyclic bond angles, the dihedral angle between the electron lone pairs of adjacent P-atoms, and the β-effect. On the basis of the X-ray and chemical shift data of 1, the bond angles of other cyclotriphosphanes can be deduced from their δ(31P) values. 1 crystallizes triclinically in the space group P1̄ with Z = 4 formula units. The X-ray analysis confirms the NMR-spectroscopically determined three-membered ring structure with the tert-butyl substituents on either side of the ring plane. Due to steric hindrance between the two tert-butyl groups in cis position, the corresponding P-P-C-bond angles show the largest values so far observed for organylcyclophosphanes.

Reflection in the 1H NMR spectrum of 37Cl/35Cl isotope effects on the 19F NMR chemical shifts of 1-chloro-2,4-difluorobenzene. An isotope effect over five bonds

1996 ◽  
Vol 74 (10) ◽  
pp. 1810-1814 ◽  
Author(s):  
Ted Schaefer ◽  
Guy M. Bernard ◽  
Frank E. Hruska
Keyword(s):  
Isotope Effect ◽  
Isotope Shift ◽  
Chemical Shifts ◽  
Isotope Effects ◽  
Coupling Constants ◽  
Nmr Spectrum ◽  
H Nmr ◽  
Resonance Frequencies ◽  
High Resolution Nmr ◽  
The Difference

In an ABX high-resolution NMR spectrum the detection of combination peaks in the X region yields only the chemical shift of X, JAX + JBX and the positive quantities [Formula: see text]. However, the presence of an additional isotopic perturbation on νA − νB, the difference between the resonance frequencies of A and B, yields two X spectra; therefore four quantities, C. Hence all quantities in the surd become available from the composite X spectrum. A generalization to ABMRX spin systems, applicable to the 1H and 19F NMR spectra of the two isotopic molecules of 1-chloro-2,4-difluorobenzene, is possible. It turns out that, from the H-5(X) spectrum alone, the following spectral quantities are extractable; the two values of νA − νB where A and B are the 19F nuclei; JAB; JAX and JBX with their relative signs; JMX and JRX where M and R are H-3 and H-6. No 37Cl/35Cl isotope effect is detectable on the 1H shielding nor on any coupling constants. F-2 undergoes an isotope shift of −1.64(3) ppb. The isotope shift, over five formal bonds, of F-4 is −0.54(3) ppb (larger shielding in the presence of 37Cl). This magnitude is three times larger than that over four formal bonds in another molecule, 2,6-dichloro-4-fluorophenol. Key words: 1H NMR, of 1-chloro-2,4-difluorobenzene, isotope effects in NMR, reflection of 37Cl/35Cl isotope effects on 19F shielding in the 1H NMR spectrum of 1-chloro-2,4-difluorobenzene; isotope effects in NMR, over three and five bonds by 37Cl/35Cl on 19F shielding in 1-chloro-2,4-difluorobenzene; 19F NMR, 37Cl/35Cl isotope effects over three and five bonds in 1-chloro-2,4-difluorobenzene.

Beiträge zur Chemie des Phosphors, 161 [1] Kernresonanzspektren und Struktur von Heptaphosphan(3), P7H3 / Contributions to the Chemistry of Phosphorus, 161 [1] NMR Spectra and Structure of Heptaphosphane(3), P7H3

1985 ◽  
Vol 40 (11) ◽  
pp. 1424-1429 ◽  
Author(s):  
Marianne Bäudler ◽  
Renate Riekehof-Böhmer
Keyword(s):  
Nmr Spectra ◽  
Chemical Shifts ◽  
Spatial Arrangement ◽  
Complete Analysis ◽  
Hydrogen Atoms ◽  
Nmr Spectrum ◽  
H Nmr

Heptaphosphane(3) (1) is obtained pure by the reaction of (Me3Si)3P7 with methanol and has been characterized NMR spectroscopically (in nascent state). It turned out to be a mixture of two diastereomers P7H3sym and P7H3asym, which differ in the spatial arrangement of the hydrogen atoms. Both isomers were proven to possess the earlier reported structure of a tri-cyclo[2.2.1.02,6]heptaphosphane, which in the case of P7H3sym was ascertained by a complete analysis of its 31P{1H} NMR spectrum. As shown by the chemical shifts, the P7 cage in P7H3sym is clearly stretched compared with P7Me3sym and (Me3Si)3P7.

scholarly journals Beiträge zur Chemie des Phosphors, 204. Zur Existenz eines Triphosphacyclobutenid-Ions P3CH2Ɵ / Contributions to the Chemistry of Phosphorus, 204. On the Existence of a Triphosphacyclobutenide Ion P3CH2e

1990 ◽  
Vol 45 (8) ◽  
pp. 1139-1142 ◽  
Author(s):  
Marianne Baudler ◽  
Josef Hahn
Keyword(s):  
White Phosphorus ◽  
Complete Analysis ◽  
Nmr Spectrum ◽  
H Nmr ◽  
Low Field

The structure of the reaction product of white phosphorus and sodium in diglyme which exhibits a low field AB2 system in the 31P{1H} NMR spectrum [4] has been reexamined. According to the results of a complete analysis of its proton coupled 31P NMR spectrum (ABB′XX′ system), the compound is the hitherto unknown 1,2,3-triphosphacyclopentadienide ion P3(CH)2⊖ (4), and not the triphosphacyclobutenide ion P3CH2⊖(3) previously assumed [4]. The parameters of the Ρ,Η-coupled 31P NMR spectrum of the tetraphosphacyclopentadienide ion P4CH⊖ (2) have also been calculated.

The planar conformation of 2-methylthiobenzaldehyde in solution

1983 ◽  
Vol 61 (1) ◽  
pp. 26-28
Author(s):  
Ted Schaefer ◽  
Rudy Sebastian
Keyword(s):  
Chemical Shifts ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Spectral Parameters ◽  
H Nmr ◽  
Heavy Atoms ◽  
Planar Conformation ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling ◽  
Infrared Data

The 1H nmr spectral parameters are extracted for a 4 mol% solution of 2-methylthiobenzaldehyde in CCl4 at 305 K. The long-range spin–spin coupling constants involving the aldehydic and methyl protons are consistent only with a preferred conformation in which all heavy atoms are coplanar, as are the chemical shifts of the ring and methyl protons. This conclusion contradicts previous interpretations of the dipole moment, the nmr parameters, and of the infrared data for CCl4 solutions. The present data show that the O-syn and O-anti forms of the compound are present in roughly equal proportions.

Neue Untersuchung über Inhaltsstoffe aus Aloe-und Rhamnus-Arten, XV [1] Homonataloin A und B aus Aloe lateritia: Reindarstellung, Konstitutions-und Konfigurationsaufklärung der Diastereomeren / A New Investigation on Constituents of Aloe and Rhamnus Species, XV [1] Hom onataloins A and B from Aloe lateritia: Isolation, Structure and Configurational Determ ination of the Diastereomers

1991 ◽  
Vol 46 (3-4) ◽  
pp. 177-182 ◽  
Author(s):  
Hans-W. Rauwald ◽  
Deo-D. Niyonzima
Keyword(s):  
Chemical Shifts ◽  
Optical Rotation ◽  
Coupling Constants ◽  
Cd Spectra ◽  
Large Coupling ◽  
H Nmr ◽  
Leaf Exudate ◽  
Hydroxyl Protons ◽  
Nmr Signals ◽  
C Nmr

From the leaf exudate of Aloe lateritia ENGLER the C-glucosyl com pounds homonataloin, aloeresin A and aloesin (synon. aloeresin B) were isolated together with the anthraquinone nataloeem odin-8-methylether and spectroscopically identified. Hom onataloin, widely distributed in Aloe species, was separated into homonataloin A and B by combined TLC and DCCC. In their 1 D and 2D 1H NMR spectra only the shifts of the 2′-hydroxyl protons of both glucosyl residues differ significantly, indicative of 10 S (A) resp. 10 S (B) configurations. In both com pounds the anthrone is in β-position of the D-glucopyranosyl, as determined by the large coupling constants of the anomeric protons. The 13C NMR signals are unambiguously assigned by the use of DEPT, APT and gated-decoupling methods. Only the chemical shifts of C -11 and C -14 show significant differences between both diastereomers due to the adjacent 2′-sugar hydroxyls. The two homonataloins differ mostly in optical rotation and circulardichroism due to different configurations at C - 10 of the anthrone part. The absolute configurations of the diastereomers are determined by correlation of their CD spectra with the CD spectra of the structural analogues 7-hydroxyaloins A and B, which shows that hom onataloin A is the 10 S, 1′S-compound and that homonataloin B has 10 R, 1′S-configuration.

Beiträge zur Chemie des Phosphors, 234 [1,2] Lithium-tetrahydrogencyclopentaphosphid: Synthese, Struktur und Reaktionen / Contributions to the Chemistry of Phosphorus, 234 [1,2] Lithium Tetrahydrogen Cyclopentaphosphide: Synthesis, Structure and Reactions

1995 ◽  
Vol 50 (5) ◽  
pp. 786-790 ◽  
Author(s):  
Marianne Baudler ◽  
Rudolf Heumüller ◽  
Wolfgang Faber
Keyword(s):  
Low Temperature ◽  
Complete Analysis ◽  
Lemon Yellow ◽  
Compound I ◽  
Polar Solvents ◽  
Open Chain ◽  
Nmr Spectrum ◽  
H Nmr ◽  
Nmr Parameters ◽  
Reaction Compound

Abstract Lithium tetrahydrogen cyclopentaphosphide. LiH4P5 (I). has been obtained by metalation of P2H4 at -78 °C with either n-BuLi or LiPH2 in polar solvents. Upon suitable performance of the reaction, compound I can be isolated at low temperature as a lemon-yellow solvent adduct. The structure as the monolithium salt of (PH)5 was confirmed by a complete analysis of the 31P{1H}-NMR spectrum. On warming above -35 °C, disproportionation occurs yield­ing Li2HP7. P2H4. and PH3. The reaction with n-BuLi produces the open-chain phosphides LiH4P3. LiH3P2, and LiPH2. The NMR parameters of LiH3P2 and LiH4P3 are reported. Reac­tion of 1 with P2H4 gives rise to the bicyclic and polycyclic phosphides LiH4P7, LiH5P8 and Li2H2P14, respectively.

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