Precise Measurement of Long-Range Heteronuclear Coupling Constants by a Novel Broadband Proton-Proton-Decoupled CPMG-HSQMBC Method

The signs of all proton–proton and proton–fluorine spin–spin coupling constants in 2-fluoro-3-methylpyridine have been determined by double and triple resonance experiments. The signs of the longrange coupling constants, JH,CH3 and JF,CH3 are the same as in fluorotoluene derivatives. Their magnitudes are consistent with the assumption that the nitrogen atom primarily polarizes the σ bonds in the molecule, leaving the π contribution to the long-range coupling relatively unaffected.

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Concerning the long-range proton-proton spin-spin coupling constants and the internal rotation barrier in styrene

Journal of Molecular Spectroscopy ◽

10.1016/0022-2852(76)90340-4 ◽

1976 ◽

Vol 61 (3) ◽

pp. 479-480 ◽

Cited By ~ 7

Author(s):

Ted Schaefer ◽

William J.E. Parr

Keyword(s):

Internal Rotation ◽

Long Range ◽

Proton Spin ◽

Coupling Constants ◽

Spin Coupling ◽

Rotation Barrier ◽

Proton Proton ◽

Internal Rotation Barrier ◽

Spin Coupling Constants ◽

Spin Spin Coupling

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Elucidation of amino acid spin systems in proteins and determination of heteronuclear coupling constants by carbon-proton-proton three-dimensional NMR

Journal of Magnetic Resonance (1969) ◽

10.1016/0022-2364(91)90285-2 ◽

1991 ◽

Vol 92 (2) ◽

pp. 434-438 ◽

Cited By ~ 12

Author(s):

Arthur S Edison ◽

William M Westler ◽

John L Markley

Keyword(s):

Amino Acid ◽

Three Dimensional ◽

Spin Systems ◽

Coupling Constants ◽

Proton Proton ◽

Heteronuclear Coupling

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CSSF-CLIP-HSQMBC: measurement of heteronuclear coupling constants in severely crowded spectral regions

RSC Advances ◽

10.1039/c9ra04118d ◽

2019 ◽

Vol 9 (62) ◽

pp. 36082-36087 ◽

Cited By ~ 1

Author(s):

Aitor Moreno ◽

Kine Østnes Hansen ◽

Johan Isaksson

Keyword(s):

Chemical Shift ◽

Long Range ◽

Program Development ◽

Coupling Constants ◽

Selective Filtration ◽

User Friendly ◽

Heteronuclear Coupling

A new pulse program development, a chemical shift selective filtration clean in-phase HSQMBC (CSSF-CLIP-HSQMBC), is presented for the user-friendly measurement of long-range heteronuclear coupling constants in severely crowded spectral regions.

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An Investigation of Long-range Proton–Proton Coupling Constants in Phenylacetylene Derivatives

Canadian Journal of Chemistry ◽

10.1139/v72-328 ◽

1972 ◽

Vol 50 (13) ◽

pp. 2035-2040 ◽

Cited By ~ 4

Author(s):

C. J. MacDonald ◽

G. K. Hamer ◽

I. R. Peat ◽

W. F. Reynolds

Keyword(s):

Hyperfine Interaction ◽

Long Range ◽

Excellent Agreement ◽

Quantitative Estimation ◽

Theoretical Calculations ◽

Experimental Results ◽

Coupling Constants ◽

Proton Proton ◽

Proton Coupling

Signs and magnitudes of long-range coupling constants in three phenylacetylene derivatives have been determined. Values of the coupling constants are discussed in terms of the McConnell formulation and compared with results of MO–INDO–FPT calculations. Coupling constants are dominated by π contributions. Estimated values of hyperfine interaction constants for acetylene and methylacetylene groups are respectively QCC≡CH = −12 and QCC≡CCH = +12 G. The theoretical calculations are in excellent agreement with experimental results. Both approaches allow quantitative estimation of nine bond couplings in 4-vinylphenylacetylene.

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Studies on the PMR Spectra of Oxetanes. VI 2-(3-Chlorophenyl)oxetane and 2-(2-Chlorophenyl)oxetane at 60 and 100 MHz

Zeitschrift für Naturforschung A ◽

10.1515/zna-1974-1229 ◽

1974 ◽

Vol 29 (12) ◽

pp. 1902-1906 ◽

Cited By ~ 2

Author(s):

Jukka Jokisaari

Keyword(s):

Long Range ◽

Chemical Shifts ◽

Methine Proton ◽

Coupling Constants ◽

Coupling Constant ◽

Proton Proton ◽

Temperature Range ◽

Proton Coupling ◽

Phenyl Proton ◽

Pmr Spectra

The 100 MHz spectra of the phenyl protons in 2-(3-chlorophenyl) oxetane and 2-(2-chlorophenyl) oxetane have been analysed. The 60 MHz PMR chemical shifts and proton-proton coupling constants have been studied in the temperature range from -20 C to +80 °C. The chemical shifts were sensitive to temperature, while the coupling constants were not, except the long range 5Jm coupling constant between the methine proton and the meta positioned phenyl proton in 2-(2-chlorophenyl) oxetane.

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