<sup>14</sup>N nuclear magnetic resonance of some monosubstituted pyridines

Saluvere, T.; Stefaniak, L.; Januszewski, H.; Webb, G. A.

doi:10.1080/00268977200101051

Cited by 18 publications

(3 citation statements)

References 28 publications

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“…Additivity rules for shifts in azoles (1642) have been discussed. Nitrogen-14 NMR studies have included azides (1643), azoles and their benzo derivatives (1644), 1,5-disubstituted tetrazoles (1645), mono-substituted pyridines (1646), O-substituted N-ethylpyridinium cations (1647), six-membered aromatic heterocycles (1648), and azo compounds and hyponitrite ion (1649).…”

Section: Nitrogen-14mentioning

confidence: 99%

Nuclear magnetic resonance spectrometry

Wasson¹,

Johnson²

1974

Anal. Chem.

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Section: Nitrogen-14mentioning

confidence: 99%

Nuclear magnetic resonance spectrometry

Wasson¹,

Johnson²

1974

Anal. Chem.

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“…A comparison of ABEN18 data from Table 1 with existing 14N chemical shift values for a limited series of pyridines (Fig. 5 ) (15) shows a rather poor correlation (r < 0.65) in that large changes in ABE do not appear to lead to predictable 14N shifts particularly for electron withdrawers. Gelius et al (16) have questioned the overall applicability of comparisons between nmr and ESCA chemical shifts since the factors responsible for each shift depend upon different terms; the present data would appear to support this conclusion at least for pyridines.…”

Section: Correlations Between B E N I S Values With Pyridine I4n Nmr mentioning

confidence: 99%

N_1s core binding energies for 2-, 3-, and 4-substituted pyridines determined by X-ray photoelectron spectroscopy. Correlations with theoretical models, substituent parameters, and gas phase basicities

Brown¹,

Tse²

1980

Can. J. Chem.

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Can. J. Chem. 58,694 (1980). N,, binding energies for 36 pyridines substituted at the 2-, 3-, and 4-positions have been determined by X-ray photoelectron spectroscopy. The differences in BE relative to pyridine are analysed in terms of existing theoretical approaches (electrostatic, ground potential, and relaxation potential models) and compared with ABEc,, values calculated for analogous monosubstituted benzenes. One finds good correlations of &BENls with solution determined o-substituent values although some substituent values deviate from the correlation probably due to solution effects which are not present in the gas phase. Correlations between ABENIS and 14W nmr chemical shifts are poor, particularly for electron withdrawing substituents. The relationship between BEN,, and gas phase basicity values (AGO) is good, and it appears as if the BENls is more sensitive to the substituent than AGO. MIND013 calculations on the methoxypyridines and their conjugate acids employing full geometry optimizations are presented and analysed in order to determine the effect of geometric relaxation on the gas phase basicity. R. S. BROWN et A. TSE. Can. J. Chem. 58,694(1980). On a determine les energies de liaison N,, de 36 pyridines substituees en positions 2 , 3 et 4 par la spectroscopie photoelectronique de rayons-X. On a analyse la difference des EL relatives a la pyridine en fonction d'approches theoriques existantes (modeles electrostatique. de potentiel de I'etat fondamental et de potentiel de relaxation) et on les a comparees aux valeurs de AELc18 calculees pour les benzenes monosubstitues analogues. On trouve de bonnes correlations entre les &ELN,, et les valeurs o des substituants determinees en solution bien que certaines valeurs de substituants devient de la correlation probablement par suite des effets de solution qui ne sont pas presents dans la phase gazeuse. Les correlations entre les AELN,, et les deplacements chimiques en rmn I4N ne sont pas bonnes, particulierement dans le cas des substituants electroattracteurs. La relation entre les ELNIa et les valeurs de basicitt de la phase gazeuse (AGO) sont bonnes et il semble que les ELN18sont plus sensibles aux substituants qu'aAGO. On presente des calculs MINDO/3 sur les methoxypyridines et leurs acides conjugues en utilisant une optimisation maximale de la geometrie et on les analyse dans le but de determiner l'effet de la relaxation geometrique sur la basicite de la phase gazeuse.[Traduit par le journal]

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“…La variabilite apparente dans la sCrie des ethers cycliques ainsi que la differenciation des deux sites oxygenes dans la serie des lactones en sont d'autant plus remarquables. sont voisines de celles des benzaldehydes C;r= 10,9) [3a] et des benzoquinones (x= 11,9) [20] [21] ou pour certaines series de produits azotCs [22] ne peuvent donc pas Ctre gkneralistes sans etude prealable.…”

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¹⁷O‐RMN. d'éthers, de cétones et d'esters cycliques. Détermination de constante de couplage quadrupolaire

Delseth

Kintzingcr

1982

Helvetica Chimica Acta

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13C-and 170-relaxation times measured in cyclic ethers, cyclic ketones, and lactones allowed the determination of the quadrupolar interaction at the 0-site. Values obtained for six-membered rings can be used as standard values for ethers k = 13 MHz), ketones (il= 10.5 MHz), and esters c;C= 11.5 MHz for dicoordinated and 9.5 MHz for monocoordinated 0-atom). Even within a series, no correlation is found between the 170-chemical shift and the value of quadrupolar interaction. Introduction. -Les dkplacements chimiques de 1 7 0 sont connus pour de nombreuses series de produits homologues [I]. Des regles empiriques reliant les dkplacements entre eux ou A d'autres proprietts moleculaires ont ainsi ete etablies [ 2 ] . En dkpit de progres rkcents, nous ne disposons que de peu d'information [3] concernant les constantes de couplage quadrupolaire (CCQ.), interessantes a determiner pour elles-mCmes, et qui, de plus, interviennent directement en RMN. de 1 7 0 en conditionnant la largeur des raies. Dans ce travail nous nous proposons d'une part de determiner les CCQ. de l'atome d'oxygene pour des series de composts cycliques presentant diverses fonctionnalitks et, d'autre part, de discuter la relation entre l'interaction quadrupolaire et le deplacement chimique. y 4 5 1 1 3 bX, 4 2 3 4 X = O,CH:, Y = 0 , C H 3 ~ I)Auteur a qui la correspondance doit &tre adressCe. Adresse actuelle:

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¹⁴N nuclear magnetic resonance of some monosubstituted pyridines

Cited by 18 publications

References 28 publications

Nuclear magnetic resonance spectrometry

Nuclear magnetic resonance spectrometry

N_1s core binding energies for 2-, 3-, and 4-substituted pyridines determined by X-ray photoelectron spectroscopy. Correlations with theoretical models, substituent parameters, and gas phase basicities

¹⁷O‐RMN. d'éthers, de cétones et d'esters cycliques. Détermination de constante de couplage quadrupolaire

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14N nuclear magnetic resonance of some monosubstituted pyridines

Cited by 18 publications

References 28 publications

Nuclear magnetic resonance spectrometry

Nuclear magnetic resonance spectrometry

N1s core binding energies for 2-, 3-, and 4-substituted pyridines determined by X-ray photoelectron spectroscopy. Correlations with theoretical models, substituent parameters, and gas phase basicities

17O‐RMN. d'éthers, de cétones et d'esters cycliques. Détermination de constante de couplage quadrupolaire

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¹⁴N nuclear magnetic resonance of some monosubstituted pyridines

N_1s core binding energies for 2-, 3-, and 4-substituted pyridines determined by X-ray photoelectron spectroscopy. Correlations with theoretical models, substituent parameters, and gas phase basicities

¹⁷O‐RMN. d'éthers, de cétones et d'esters cycliques. Détermination de constante de couplage quadrupolaire