Quadrupolar interactions in amines as determined by 1H nuclear magnetic resonance: mono- and dimethylamines

1984 ◽  
Vol 62 (7) ◽  
pp. 1258-1261 ◽  
Author(s):  
James D. Halliday ◽  
Patrick E. Bindner ◽  
Shahsultan Padamshi
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nmr Spectra ◽  
Molecular Reorientation ◽  
Correlation Times ◽  
Temperature Range ◽  
H Nmr ◽  
Quadrupole Interactions ◽  
1H Nuclear Magnetic Resonance ◽  
Temperature Activation

Nitrogen-14 quadrupole interactions have been observed in the nonexchanging amino proton 1H nmr spectra of rigorously purified liquid mono- and dimethylamines over the temperature range −82 °C to +81 °C. The proton lineshapes have been analyzed to yield 14N spin-lifetimes (τ) as a function of temperature. Activation energies and correlation times for molecular reorientation in the liquids have been calculated from these data and the results compared with those from 14N nmr measurements.

A 19F nuclear magnetic resonance study of the conjugate Brönsted-Lewis superacid HSO3F-SbF5. Part 1

1999 ◽  
Vol 77 (11) ◽  
pp. 1869-1886 ◽  
Author(s):  
Dingliang Zhang ◽  
Markus Heubes ◽  
Gerhard Hägele ◽  
Friedhelm Aubke
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nmr Spectra ◽  
Nuclear Magnetic Resonance Study ◽  
Magnetic Resonance Study ◽  
Formation Reaction ◽  
H Nmr ◽  
Acid Conjugate ◽  
Nmr Methods ◽  
Cis And Trans

The Brönsted-Lewis superacid HSO3F-SbF5 or "magic acid" is re-investigated by modern 19F NMR methods over a wide concentration range. The system is found to be considerably more complex than had been assumed previously. A total of 13 different anions are identified of which only five have previously been identified in magic acid. With increasing SbF5 contents the concentration of monomeric anions like [SbF6]-, [SbF5(SO3F)]-, cis- and trans-[SbF4(SO3F)2]-, and mer-[SbF3(SO3F)3]- gradually decreases. Except for [Sb2F11]-, which is present in very small concentrations only, the formation of oligomers involves exclusively μ-fluorosulfato bridges. In addition to donor (SO3F)- and acceptor (SbF5) complex formation to give [SbF5(SO3F)]- and possibly ligand redistribution, the solvolysis of SbF5 or SbF4(SO3F) in HSO3F appears to be the principal formation reaction for polyfluorosulfatofluoroantimonate(V) anions. In glass (NMR tubes) the solvolysis product HF is converted to the oxonium ion [H3O]+, which has previously been identified by 1H NMR and structurally characterized as [H3O][Sb2F11] by us.Key words: magic acid, conjugate superacid, fluorosulfuric acid, 19F NMR spectra.

sHigh resolution 1H nuclear magnetic resonance studies of a flavine and its product with MoCl4

1977 ◽  
Vol 55 (4) ◽  
pp. 575-582 ◽  
Author(s):  
T. Roberie ◽  
N. S. Bhacca ◽  
J. Selbin
Keyword(s):  
Aqueous Solution ◽  
Nuclear Magnetic Resonance ◽  
Binding Sites ◽  
Nmr Spectra ◽  
Coupling Constants ◽  
Side Chain ◽  
Magnetic Resonance Studies ◽  
H Nmr ◽  
Metal Atoms ◽  
1H Nuclear Magnetic Resonance

The high resolution 1H nmr spectra of the substituted flavine, 3-N-methyltetraacetylriboflavine (3-Me-TARF), and its non-aqueous solution complexes with Gd(fod)3, Eu(fod)3, MoCl4, and MoCl4•2CH3(CH2)2CN, were studied in order to try to discern the binding sites of the flavine as it attaches to the molybdenum. Evidence was found that all three metal atoms, Gd(III), Eu(III), and Mo(IV), are attached in solution not only by the primary binding (chelating) sites of the flavine, viz., the O-4 and N-5 atoms, but also by an acetyl oxygen atom, at the C-4′ site of the ribityl side chain. 300 MHz spectra of the 3-Me-TARF have permitted the coupling constants for the side chain methine and methylene protons to be obtained.

Quadrupolar relaxation effects in methyl-substituted ammonium ions as determined by 1H nuclear magnetic resonance

1985 ◽  
Vol 63 (11) ◽  
pp. 2975-2978 ◽  
Author(s):  
James D. Halliday ◽  
Patrick E. Bindner ◽  
Shahsultan Padamshi
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectra ◽  
Ammonium Ions ◽  
Quadrupole Interactions ◽  
Relaxation Effects ◽  
1H Nuclear Magnetic Resonance ◽  
Quadrupolar Relaxation ◽  
Magnetic Resonances ◽  
Hcl Solution ◽  
Nuclear Magnetic

Nitrogen-14 quadrupole interactions broaden the 1H nuclear magnetic resonances of the ammonium protons spin-coupled to 14N in the methyl-substituted ammonium chlorides (methylammonium, dimethylammonium, and trimethylammonium). These proton lineshapes have been determined over the temperature range −8.3 to +93.6 °C in 6 mol L−1 aqueous HCl solution. The 14N spin-lifetimes, τ, have been calculated from the Arrhenius form equation In τ vs. 1/T (K), and yield activation energies of 10.63 ± 0.92, 10.60 ± 0.52, and 11.12 ± 0.39 kJ mol−1 for the mono-, di-, and tri-methyl species, respectively. The 14N nmr linewidths have been extracted from these data and a comparison is made with 14N nmr spectra obtained by Ogg and Ray.

Aliphatic diazo compounds. XIV. The synthesis of 7-substituted 3-diazo-2-norbornanones and the infrared and proton and carbon-13 nuclear magnetic resonance spectra of these diazo ketones and their precursors

1984 ◽  
Vol 62 (9) ◽  
pp. 1751-1766 ◽  
Author(s):  
Peter Yates ◽  
John David Kronis
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Nmr Spectra ◽  
Diazo Compounds ◽  
Lower Field ◽  
Tert Butyl ◽  
H Nmr ◽  
Nuclear Magnetic Resonance Spectra ◽  
C Nmr ◽  
Shielding Effects

syn- and anti-7-Isopropyl-2-norbornanone (5 and 6) were prepared by catalytic hydrogenation of 7-isopropylidene-2-norbornanone; syn- and anti-7-benzhydryl-2-norbornane (9 and 10) were prepared in analogous fashion. Ketones 5 and 6 and syn- and anti-7-tert-butyl-2-norbornanone (7 and 8) were converted to the corresponding 3-diazo-2-norbornanones 1–4 via the monotosylhydrazones 44–47 of the corresponding α-diketones 40–43. The 1H and 13C nmr spectra of 1–10, 40–47, and their precursors have been analyzed. The 1H nmr spectra of the diazo ketones 1–4 have their C-1 and C-4 bridgehead proton signals shifted to higher and lower field, respectively, relative to the bridgehead signals of the corresponding diketones. The 13C nmr spectra of all pairs of bicyclic epimers shown γ-gauche shielding effects by the 7-substituent at (sp3) C-3 in the syn compounds and at C-5 and C-6 in the anti compounds. A converse effect is found at (sp2) C-2 (and C-3 in the diketones). Comparison of the magnitude of the shielding effects of C-7 methyl, isopropyl, benzhydryl, and tert-butyl substituents gives evidence of δ deshielding effects at C-3 in the syn compounds and at C-5 and C-6 in the anti compounds by methyl substituents on C-8.

Analysis of 1H and 13C{1H} NMR Spectral Parameters of Diphenylchloroarsine, Diphenylcyanoarsine, and 10-Chloro- 5,10-Dihydrophenarsazine: Identification of the Compounds through Reference to Simulated Spectra

1997 ◽  
Vol 51 (5) ◽  
pp. 733-737 ◽  
Author(s):  
Markku Mesilaakso ◽  
Eeva-Liisa Tolppa ◽  
Paula Nousiainen
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
1H Nmr ◽  
Nmr Spectra ◽  
Spectral Parameters ◽  
H Nmr ◽  
Iterative Analysis ◽  
Simulation Of Spectra ◽  
Nuclear Magnetic

The 1H and 13C{1H} nuclear magnetic resonance (NMR) spectra of diphenylchloroarsine, diphenylcyanoarsine, and 10-chloro-5,10-dihydrophenarsazine were recorded from samples prepared in CDCl3, CD2Cl2, and (CD3)2CO. Spectra were analyzed, and detailed 1H NMR spectral parameters were determined by iterative analysis. Simulation of spectra and their use as reference spectra for identification of the compounds under different conditions are discussed.

scholarly journals Nuclear Magnetic Resonance-based Metabolomics of Blood Plasma from Dairy Calves Infected with the Main Causal Agents of Bovine Respiratory Disease (BRD)

2021 ◽  
Author(s):  
Mariana Santos-Rivera ◽  
Nicholas C. Fitzkee ◽  
Rebecca A. Hill ◽  
Richard E. Baird ◽  
Ellianna Blair ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Blood Plasma ◽  
Respiratory Disease ◽  
Nmr Spectra ◽  
Bovine Respiratory Disease ◽  
Dairy Calves ◽  
Proton Nuclear Magnetic Resonance ◽  
H Nmr ◽  
Nuclear Magnetic

Abstract Each year, Bovine Respiratory Disease (BRD) results in significant economic loss in the cattle sector, and novel metabolic profiling and early diagnosis techniques represent a promising tool for developing effective measures for disease management. Here, proton - Nuclear Magnetic Resonance (1H - NMR) spectra were used to characterize metabolites from blood plasma collected from dairy calves intentionally infected with the main BRD causal agents, bovine respiratory syncytial virus (BRSV) and Mannheimia haemolytica (MH), to generate a well-defined metabolomic profile under controlled conditions. In response to infection, 42 metabolites (BRSV = 27, MH = 24) changed in concentration compared to the Baseline (non-infected) state. Fuel substrates and products exhibited a particularly strong effect, reflecting imbalances that occur during the immune response. Glucose levels decreased only during bacterial infection, suggesting that the clinical signs of bacterial BRD are more energetically taxing than those of viral BRD. Furthermore, 1H - NMR spectra from Baseline and Infected samples were discriminated with an accuracy, sensitivity, and specificity ≥ 95% using chemometrics to model the changes associated with disease, suggesting that metabolic profiles can be used for further development and validation of diagnostic tools.

Synthesis and nuclear magnetic resonance spectra of platinum compounds with thiourea derivatives

1985 ◽  
Vol 63 (9) ◽  
pp. 2425-2429 ◽  
Author(s):  
F. D. Rochon ◽  
J. Bariyanga ◽  
P. C. Kong
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Sulfur Atom ◽  
Nmr Spectra ◽  
Intramolecular Interaction ◽  
Platinum Compounds ◽  
Thiourea Derivatives ◽  
Methyl Group ◽  
H Nmr ◽  
Nuclear Magnetic Resonance Spectra

Compounds of the type trans-[PtL2T2]Cl2 where L = NH3, methylamine, dimethylamine, pyridine, and 2-aminopyrimidine and T = N-methylthiourea and N,N′-dimethylthiourea and where L = NH3 and T = N,N,N′,N′-tetramethylthiourea have been synthesized. The 1H nmr spectra have shown that the thiourea derivatives are bonded to platinum by the sulfur atom. The methyl protons of N-methylthiourea and one methyl group protons of N,N′-dimethylthiourea in the complexes, where L is aromatic, showed resonance at higher field after coordination to the metal. This was explained by an intramolecular interaction between the methyl group and the aromatic ring. The nmr spectra of the [PtT4]Cl2 compounds were also measured.

Structures of toxic constituents in kraft mill caustic extraction effluents from 13C and 1H nuclear magnetic resonance

1977 ◽  
Vol 55 (18) ◽  
pp. 3298-3303 ◽  
Author(s):  
A. N. Thakore ◽  
A. C. Oehlschlager
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
H Nmr ◽  
1H Nuclear Magnetic Resonance ◽  
Kraft Mill ◽  
Nuclear Magnetic

Arguments based on 13C and 1H nmr spectroscopy are presented to elucidate the structures of 3,4,5- and 4,5,6-trichloroguaiacol, 12- and 14-monochlorodehydroabietic acid, and 12,14-dichlorodehydroabietic acid. These compounds were recently isolated and tentatively identified as major components toxic to fish in kraft mill caustic extraction effluents.

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