Photochemistry of aromatic N-oxides. Photochemical behavior of monosubstituted pyridine N-oxides in water solution was written by Bellamy, Francois;Streith, Jacques;Fritz, Hans. And the article was included in Nouveau Journal de Chimie in 1979.Reference of 51834-97-0 This article mentions the following:
The photolysis of monosubstituted pyridine N-oxides gives complex reaction mixtures, most of which contain pyrroles in low yields. The ring contraction is explained by the intermediacy of conjugated nitrenes. In the experiment, the researchers used many compounds, for example, 5-Hydroxy-2-methoxylpyridine (cas: 51834-97-0Reference of 51834-97-0).
5-Hydroxy-2-methoxylpyridine (cas: 51834-97-0) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Reduced pyridines, namely tetrahydropyridines, dihydropyridines and piperidines, are found in numerous natural and synthetic compounds. The synthesis and reactivity of these compounds have often been driven by the fact many of these compounds have interesting and unique pharmacological properties. Reference of 51834-97-0