Basicity of azoles. IV^†. Empirical relationships between basicity and ionization potential for aromatic five membered rings containing nitrogen or oxygen

Javier Catalán

Departamento de Química Fisica y Química Quántica, Facultad de Ciencias C-XIV, Centre- Coordinado CSIC-UAM, Universidad Autónoma de Madrid, Cantoblanco, Madrid-34 Spain

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José Elguero,

José Elguero

Instituto de Quimica Médica, CSIC, Juan de la Cierva, 3, Madrid-6, Spain

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Javier Catalán,

Javier Catalán

Departamento de Química Fisica y Química Quántica, Facultad de Ciencias C-XIV, Centre- Coordinado CSIC-UAM, Universidad Autónoma de Madrid, Cantoblanco, Madrid-34 Spain

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José Elguero,

José Elguero

Instituto de Quimica Médica, CSIC, Juan de la Cierva, 3, Madrid-6, Spain

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First published: January/February 1984

https://doi.org/10.1002/jhet.5570210156

Citations: 25

^†

Preceding parts of this series, references [2] to [4].

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Abstract

A plot of pK_a values for eleven azoles and benzazoles vs the experimental ionization energy of the nitrogen lone pair shows the existence of three groups of compounds: simple unsubstituted azoles (imidazole, pyrazole, oxazole, isoxazole), unsubstituted benzazoles (benzimidazole, 1H-indazole and benzoxazole, including imidazo [1,2-a]pyridine) and benzazoles carrying a methyl group α- to the basic centre (2-methylbenzimidazole, 2-methylindazole and 2-methylbenzoxazole).

References and Notes

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Volume21, Issue1

January/February 1984

Pages 269-270

Basicity of azoles. IV^†. Empirical relationships between basicity and ionization potential for aromatic five membered rings containing nitrogen or oxygen

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Basicity of azoles. IV†. Empirical relationships between basicity and ionization potential for aromatic five membered rings containing nitrogen or oxygen

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Basicity of azoles. IV^†. Empirical relationships between basicity and ionization potential for aromatic five membered rings containing nitrogen or oxygen