Pyridine Interactions with Phenol and Substituted Phenols

Rubin, Jerome; Senkowski, Bernard Z.; Panson, Gilbert S.

doi:10.1021/j100788a522

Cited by 18 publications

(6 citation statements)

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“…Thus the shifts due to the formation of association complexes of 22 phenols with dimethyl sulphoxide are linearly correlated with Hammett's σ constants for substituents, increasing with the acid properties of the phenol 132 . A similar relation was obtained for systems comprising meta-and parasubstituted phenols on the one hand and pyridine on the other 133 , which agrees with data for substituted phenolamine systems obtained by ultraviolet spectroscopy 134 ' 135 . On the other hand, the shift due to association involving phenols is proportional to the basicity of the electron donor 136 ' 137 .…”

Section: Phenolssupporting

confidence: 88%

Investigation of the Association of Alcohols and Phenols by the NMR Method

Brodskii¹,

Pokhodenko²,

Kuts³

1970

Russ. Chem. Rev.

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A.I.Brodskii (deceased), V.D.Pokhodenko, and V.S.KutsThe review discusses and analyses the literature on the study of the association of alcohols and phenols by the NMR method. The methods for the determination of the equilibrium constants and heats and entropies of formation of the association complexes of the above substances in both inert and basic solvents are described for equilibria of different types. The polar and steric effects of the substituents in alcohols and phenols on the thermodynamic functions for the formation of self-association complexes and also of association complexes with polar molecules has been analysed. The bibliography comprises 151 references. CONTENTS

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Section: Phenolssupporting

confidence: 88%

Investigation of the Association of Alcohols and Phenols by the NMR Method

Brodskii¹,

Pokhodenko²,

Kuts³

1970

Russ. Chem. Rev.

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“…A study of hydrogen bonding between parasubstituted phenols and dimethylacetamide showed that H-bond strength is directly proportional to the Hammett sigma value ( ) of the para functional group (Stymne et al, 1973). Similar results were obtained with a parasubstituted phenol/pyridine model (Rubin et al, 1964). Hydrogen bond strength is therefore controlled by the electron-donating or-withdrawing power of the para substituent.…”

supporting

confidence: 54%

Synthesis and sensory evaluation of ring-substituted dihydrochalcone sweeteners

Whitelaw¹,

Daniel²

1991

J. Agric. Food Chem.

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“…Plusieurs auteurs ont utilise I'kquation prectdente dans I'etude des complexes a liaison hydrogene. Par exemple, pour les complexes de phenols substituks avec les sulfoxydes [4] ou avec I'acetone [5], la pyridine [6] ou de pyridines substitubes avec le phenol [7], oh les constantes de formation sont dkterminees par spectrometrie infrarouge; pour les complexes du p.fluorophCnol avec diverses bases [8] o h la methode utiliske est la resonance magnetique nucleaire du fluor [9]. Les relations de Hammett sont egalement appliquees aux constantes de formation des picrates d'aniline, determinees par spectrometrie ultraviolette dans le dioxanne [9] ou I'acetonitrile [lo].…”

Section: Introductionunclassified

Étude par Spectrométrie Infrarouge de la Complexation Entre les Phénols Substitués et les Pyridines Substituées

Clotman

Müller

Zeegers‐Huyskens

1970

Bulletin des Soc Chimique

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Complexation constants of hydrogen bonded complexes between substituted phenols and substituted pyridines were determined by infrared spectroscopic measurements in carbon tetrachloride at 25OC. It was previously shown that for monosubstitutedJcomplexes the complexation constant Kab obied the relation log KOb = log Ko+pu where u is the Hammett substitution constant. When both the proton donor and the proton acceptor are substituted, it is shown in the present work that the logarithm of the complexation constant can be expressed by the equation:where KO, refers to the unsubstituted complexe phenol-pyridine: p: is the pa value when ub is zero and p$ the pb value when a,, is zero. The product &,pb is an interaction term where B = -037. This relation shows that an increasing acidity of phenol enhances the substitution effects on the pyridine. This interaction term is discussed in terms of dipolar and polarisation effects. A similar equation was previously found for the phenol-aniline disubstituted complexes. In the present case, the p: and p: values are greater owing to the stronger basicity of pyridine, and to the smaller O . . . N distance. The E constant however is greater with the aniline (-1.70) than with the pyridine complexes. This fact is discussed in terms of the variation of hybridization of the nitrogen atom in the complexes, which in the case of aniline, can be deduced from HNH angle measurements.

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Pyridine Interactions with Phenol and Substituted Phenols

Cited by 18 publications

References 0 publications

Investigation of the Association of Alcohols and Phenols by the NMR Method

Investigation of the Association of Alcohols and Phenols by the NMR Method

Synthesis and sensory evaluation of ring-substituted dihydrochalcone sweeteners

Étude par Spectrométrie Infrarouge de la Complexation Entre les Phénols Substitués et les Pyridines Substituées

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