Towards quantifying the role of exact exchange in the prediction hydrogen bond spin-spin coupling constants involving fluorine

2016 ◽  
Vol 145 (8) ◽  
pp. 084301 ◽  
Author(s):  
J. San Fabián ◽  
S. Omar ◽  
J. M. García de la Vega
Keyword(s):  
Hydrogen Bond ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Spin Coupling Constants ◽  
Exact Exchange ◽  
Spin Spin Coupling

Proton spin–spin coupling constants and intramolecular hydrogen bonding in bromine derivatives of 1,3-dihydroxybenzene

1976 ◽  
Vol 54 (14) ◽  
pp. 2228-2230 ◽  
Author(s):  
Ted Schaefer ◽  
J. Brian Rowbotham
Keyword(s):  
Hydrogen Bond ◽  
Hydrogen Bonding ◽  
Proton Spin ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Hydroxyl Groups ◽  
Oh Groups ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling ◽  
Derivatives Of

The conformational preferences in CCl4 solution at 32 °C of the hydroxyl groups in bromine derivatives of 1,3-dihydroxybenzene are deduced from the long-range spin–spin coupling constants between hydroxyl protons and ring protons over five bonds. Two hydroxyl groups hydrogen bond to the same bromine substituent in 2-bromo-1,3-dihydroxybenzene but prefer to hydrogen bond to different bromine substituents when available, as in 2,4-dibromo-1,3-dihydroxybenzene. When the OH groups can each choose between two ortho bromine atoms, as in 2,4,6-tribromoresorcinol, they apparently do so in a very nearly statistical manner except that they avoid hydrogen bonding to the common bromine atom.

Concerning the nonexistence of the intramolecular hydrogen bond in 2-nitrothiophenol

1977 ◽  
Vol 55 (21) ◽  
pp. 3732-3735 ◽  
Author(s):  
Ted Schaefer ◽  
William J. E. Parr
Keyword(s):  
Hydrogen Bond ◽  
Free Energy ◽  
Intramolecular Hydrogen Bond ◽  
Energy Difference ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Free Energy Difference ◽  
Spin Coupling Constants ◽  
Intramolecular Hydrogen ◽  
Spin Spin Coupling

The long-range spin–spin coupling constants between the sulfhydryl proton and the ring protons in 2-nitrothiophenol in CDCl3 and C6D6 solutions suggest the presence of two conformers in which the S—H bond prefers the benzene plane. The conformer in which the S—H bond lies trans to the nitro group is favoured over the cis conformer by a free energy difference of 0.5 ± 0.2 kcal/mol at 305 K. Apparently any intramolecular hydrogen bond is very weak compared to that in 2-nitrophenol.

The three conformations of 3,5-dichloro-2-hydroxythiophenol in solution

1981 ◽  
Vol 59 (22) ◽  
pp. 3204-3207
Author(s):  
Ted Schaefer ◽  
Richard P. Veregin ◽  
David M. McKinnon
Keyword(s):  
Hydrogen Bond ◽  
Free Energy ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
The Other ◽  
Spin Coupling ◽  
Ring Plane ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling ◽  
Energy Preference

The long-range spin–spin coupling constants for the sidechain protons in 3,5-dichloro-2-hydroxythiophenol show that the compound exists as a mixture of three conformers in CCl4 solution at 305 K. The conformer, in which the S—H bond is held roughly perpendicular to the ring plane by an [Formula: see text] hydrogen bond, is 13% abundant. The other two conformers, of roughly equal proportions, contain an [Formula: see text] hydrogen bond. One of these has the S—H bond cis to the OH group, the other has it trans. The chemical shifts of the SH proton and of H-6 are in agreement with these conclusions. The free energy preference of the [Formula: see text] over the [Formula: see text] bond is 1140 ± 100 cal/mol at 305 K. The five-bond coupling between the sidechain protons is negative and very likely involves proximate interactions via lone pairs on oxygen and/or sulfur.

Vibrational and thermal averaging of the indirect nuclear spin-spin coupling constants of CH4, SiH4, GeH4 and SnH4

1997 ◽  
Vol 91 (5) ◽  
pp. 897-907 ◽  
Author(s):  
SHEELA KIRPEKAR ◽  
THOMAS ENEVOLDSEN ◽  
JENS ODDERSHEDE ◽  
WILLIAM RAYNES
Keyword(s):  
Nuclear Spin ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling
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