In organic chemistry, atoms other than carbon and hydrogen are generally referred to as heteroatoms. The most common heteroatoms are nitrogen, oxygen and sulfur. Now I present to you an article called Influence of solvents on intramolecular hydrogen bonds with large proton polarizability, published in 1982-07-31, which mentions a compound: 1127-45-3, mainly applied to hydrogen bond intramol NMR; proton polarizability hydrogen bond NMR, Synthetic Route of C9H7NO2.
A large number of compounds with intramol. hydrogen bonds with great proton polarizability were studied by 1H NMR in solvents of various polarities. With the homoconjugated hydrogen bonds, small changes of the chem. shift of the hydrogen-bonded proton are observed with increasing polarity of the solvent, whereby the signal shifts toward lower field. This effect is explained by increasing removal of the counterions from the homoconjugated hydrogen bonds and thus, by decreasing induced dipole interaction of the counterions and the hydrogen bonds with great proton polarizability. In the case of heteroconjugated hydrogen bonds analogous but much greater shifts are observed They are explained by a shift of the OH···N ⇌ O-···H+N equilibrium to the right-hand side with increasing polarity of the solvent. With hydrogen bonds showing no great proton polarizability these effects do not occur.
If you want to learn more about this compound(8-Hydroxyquinoline 1-oxide)Synthetic Route of C9H7NO2, you may wish to communicate with the author of the article,or consult the relevant literature related to this compound(1127-45-3).
Reference:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider