Scalar coupling values

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Contents

Aromatic groups

Ortho 6-9 Hz
Meta 1-3 Hz
Para 0-1 Hz

All couplings of same sign (?)

Nucleotides

Article [1] has a diagram with some J couplings in Ade base.

Vicinal couplings

Ethylene - trans 19.0 Hz; cis - 11.7 Hz. Values are reduced by electronegative substituents. Approx as:
Jtrans = 19.0 - 3.3δE
Jcis = 11.7 - 4.0δE
where δE is Electronegativity in Huggins scale, relative to proton.

Geminal couplings

Ethylene 2.5 Hz (Ref 11 in paper below). Decreases with increase of electronegativity of X in CH2=CHX. +7.5 Hz where X=Li, -3.2 Hz where X=F

References

  1. http://dx.doi.org/10.1007/s10858-009-9323-1 [schwalbe09]
  2. Banwell, CN and Sheppard, N. (H, H) coupling constants in the nuclear magnetic resonance spectra of hydrocarbon groupings. Discussions of the Faraday Society 34:115--126, 1962. BibTeX [banwell62]

  3. Huggins, ML. Bond Energies and Polarities. Journal of the American Chemical Society 75(17):4123--4126, 1953. BibTeX [huggins53]

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