Epoxy compounds usually have stronger nucleophilic ability, because the alkyl group on the oxygen atom makes the bond angle smaller, which makes the lone pair of electrons react more dissimilarly with the electron-deficient system. Compound: 5-Hydroxynicotinic acid, is researched, Molecular C6H5NO3, CAS is 27828-71-3, about NMR study of acid-base reactions of 3-hydroxypyridine, 3-hydroxypyridine N-oxide, and β-hydroxypyridinecarboxylic acids.Quality Control of 5-Hydroxynicotinic acid.
An NMR method was used to determine the protonation and ionization constants of 3-hydroxypyridine (I) and its N-oxide (II); 5-hydroxynicotinic acid, 3-hydroxyisonicotinic acid (III), and their Et esters; and 5-hydroxypicolinic acid. Introduction of the CO2H group at different positions of the β-hydroxypyridine ring generally had a deshielding effect on the ring protons. The ionization of the CO2H group in nicotinic and picolinic acid was not appreciably affected by introduction of the OH group. Ionization of III was hindered by intramol. H bonding between the OH and CO2H groups. The acidity of II was much greater than that of I.
There is still a lot of research devoted to this compound(SMILES：O=C(O)C1=CN=CC(O)=C1)Quality Control of 5-Hydroxynicotinic acid, and with the development of science, more effects of this compound(27828-71-3) can be discovered.
Reference:
Chapter 1 An introduction to palladium catalysis,
Palladium/carbon catalyst regeneration and mechanical application method