scholarly journals The Concentration Effect of the Long-range Proton Spin-spin Coupling Constant in Ketones

1964 ◽  
Vol 37 (2) ◽  
pp. 291-291 ◽  
Author(s):  
Kensuke Takahashi
Keyword(s):  
Long Range ◽  
Proton Spin ◽  
Spin Coupling ◽  
Concentration Effect ◽  
Coupling Constant ◽  
Spin Coupling Constant ◽  
Spin Spin Coupling

The sign of the long-range spin–spin coupling constant between 19F and the aldehydic 1H in p-fluorobenzaldehyde: evidence for a negative QCCHO

1969 ◽  
Vol 47 (22) ◽  
pp. 4289-4291 ◽  
Author(s):  
T. Schaefer ◽  
S. S. Danyluk
Keyword(s):  
Hyperfine Interaction ◽  
Long Range ◽  
Interaction Constant ◽  
Spin Coupling ◽  
Coupling Constant ◽  
Spin Coupling Constant ◽  
Spin Spin Coupling

The spin–spin coupling constant of −0.50 ± 0.03 Hz between the 19F nucleus and the aldehydic proton in p-fluorobenzaldehyde contrasts with a positive coupling between 19F and methyl protons in p-fluorotoluene derivatives. If the former coupling is dominated by a π electron mechanism, it implies a negative hyperfine interaction constant between the aldehydic proton and the aromatic π system.

Signs of long-range amino proton – ring proton coupling constants in N-ethyl-4-chloro-2-nitroaniline

1970 ◽  
Vol 48 (8) ◽  
pp. 1343-1345 ◽  
Author(s):  
T. Schaefer ◽  
R. Wasylishen
Keyword(s):  
Long Range ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Coupling Constant ◽  
Spin Coupling Constant ◽  
Proton Resonance ◽  
Ring Proton ◽  
Multiple Resonance ◽  
Proton Coupling ◽  
Spin Spin Coupling

In N-ethyl-4-chloro-2-nitroaniline there exists a measurable indirect spin–spin coupling constant of ±0.39 ± 0.03 Hz between the methylene protons and ring proton 6. The amino proton is coupled to ring protons 5 and 6 and also to the methylene protons. Consequently, although the amino proton resonance is broad due to incompletely relaxed coupling to 14N, normal multiple resonance experiments show that 5JmH,NH = 0.67 ± 0.03 Hz and 4JoH,NH = −0.35 ± 0.03 Hz.

An estimate of the spin–spin coupling constant, 1J(1H,13C), in gaseous benzene

1996 ◽  
Vol 74 (8) ◽  
pp. 1524-1525 ◽  
Author(s):  
Ted Schaefer ◽  
Guy M. Bernard ◽  
Frank E. Hruska
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Dielectric Constant ◽  
Magnetic Resonance ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Coupling Constant ◽  
Spin Coupling Constant ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling ◽  
Gaseous Benzene

An excellent linear correlation (r = 0.9999) exists between the spin–spin coupling constants 1J(1H,13C), in benzene dissolved in four solvents (R. Laatikainen et al. J. Am. Chem. Soc. 117, 11006 (1995)) and Ando's solvation dielectric function, ε/(ε – 1). The solvents are cyclohexane, carbon disulfide, pyridine, and acetone. 1J(1H,13C)for gaseous benzene is predicted to be 156.99(2) Hz at 300 K. Key words: spin–spin coupling constants, 1J(1H,13C) for benzene in the vapor phase; spin–spin coupling constants, solvent dielectric constant dependence of 1J(1H,13C) in benzene; benzene, estimate of 1J(1H,13C) in the vapor; nuclear magnetic resonance, estimate of 1J(1H,13C) in gaseous benzene.

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