ChemInform Abstract: NMR and MO Study of Internal Hydrogen Bonding in Salicyl Alcohol. Principal Site Analysis Based on the Sidechain Methylene and Hydroxy Proton Long-Range Coupling Constants

13C Chemical shifts and resolved carbon–proton couplings of 39 deoxybenzoins and 11 acetophenones, most of which have naturally occurring substitution patterns, are assigned. Individual benzene rings turned out to have typical parameters not affected by structural variations in the rest of the molecule. Due to substitutional saturation, however, these benzenoid carbon shifts markedly deviate from increment additivity. A few trends of these deviations are described. Phenolic hydrogens, fixed between hydroxyl and carbonyl oxygen due to internal hydrogen bonding, are shown to give rise to additional carbon-splittings.

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How to measure long-range proton-carbon coupling constants from 1 H-selective HSQMBC experiments

Magnetic Resonance in Chemistry ◽

10.1002/mrc.4928 ◽

2019 ◽

Vol 58 (5) ◽

pp. 363-375 ◽

Cited By ~ 2

Author(s):

Josep Saurí ◽

Pau Nolis ◽

Teodor Parella

Keyword(s):

Long Range ◽

Coupling Constants

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BIRD-J -resolved HMBC and BIRD-high-resolution HMBC pulse sequences for measuring heteronuclear long-range coupling constants and proton-proton spin coupling constants in complicated spin systems

Magnetic Resonance in Chemistry ◽

10.1002/mrc.2702 ◽

2011 ◽

Vol 49 (2) ◽

pp. 53-58 ◽

Cited By ~ 9

Author(s):

Kazuo Furihata ◽

Mitsuru Tashiro ◽

Haruo Seto

Keyword(s):

High Resolution ◽

Long Range ◽

Pulse Sequences ◽

Spin Systems ◽

Proton Spin ◽

Coupling Constants ◽

Spin Coupling ◽

Proton Proton ◽

Spin Coupling Constants

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NMR Properties of the Cyanide Anion, a Quasisymmetric Two-Faced Hydrogen Bonding Acceptor

Symmetry ◽

10.3390/sym13071298 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1298

Author(s):

Ilya G. Shenderovich ◽

Gleb S. Denisov

Keyword(s):

Hydrogen Bonding ◽

Experimental Studies ◽

Polarizable Continuum Model ◽

Coupling Constants ◽

Scalar Coupling ◽

Cyanide Anion ◽

Molecular Systems ◽

Polarizable Continuum ◽

Chemical Shieldings ◽

Nmr Properties

The isotopically enriched cyanide anion, (13C≡15N)−, has a great potential as the NMR probe of non-covalent interactions. However, hydrogen cyanide is highly toxic and can decompose explosively. It is therefore desirable to be able to theoretically estimate any valuable results of certain experiments in advance in order to carry out experimental studies only for the most suitable molecular systems. We report the effect of hydrogen bonding on NMR properties of 15N≡13CH···X and 13C≡15NH···X hydrogen bonding complexes in solution, where X = 19F, 15N, and O=31P, calculated at the ωB97XD/def2tzvp and the polarizable continuum model (PCM) approximations. In many cases, the isotropic 13C and 15N chemical shieldings of the cyanide anion are not the most informative NMR properties of such complexes. Instead, the anisotropy of these chemical shieldings and the values of scalar coupling constants, including those across hydrogen bonds, can be used to characterize the geometry of such complexes in solids and solutions. 1J(15N13C) strongly correlates with the length of the N≡C bond.

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