Science and Mathematics Faculty Publications
Ionization in Liquid Ammonia of Methyl and Amino Groups Bonded to Pyridine and Pyrazine. A Method of Determining Their pKa Values
Document Type
Article
Publication Date
1973
Journal Title
Journal of Organic Chemistry
Volume
38
Issue
4
First Page
658
Last Page
662
Abstract
Proton magnetic resonance spectra of ionized 2-methyl and 2-amino derivatives of pyridine and pyrazine along with spectra of 2-pyridone and 2-pyrazinone in liquid ammonia are reported. Changes in chemical shifts produced by ionization of the pyridines are linearly related to those for the pyrazines. Competition experiments show that 2-methyl- is less acidic than 4-methylpyridine; estimates of the pK, values for these two acids are given. It is suggested that the results provide a basis for determining the equilibrium acidities of weak heterocyclic acids.
Keywords
ionization, liquid ammonia, pyridine, pyrazine
Recommended Citation
Helmick, L. S. (1973). Ionization in Liquid Ammonia of Methyl and Amino Groups Bonded to Pyridine and Pyrazine. A Method of Determining Their pKa Values. Journal of Organic Chemistry, 38, 658-662.
