The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Spectrophotometric studies of iron(III)-8-quinolinol N-oxide complex》. Authors are Bhat, A. N.; Jain, B. D..The article about the compound:8-Hydroxyquinoline 1-oxidecas:1127-45-3,SMILESS:OC1=CC=CC2=CC=C[N+]([O-])=C12).Quality Control of 8-Hydroxyquinoline 1-oxide. Through the article, more information about this compound (cas:1127-45-3) is conveyed.
Spectrophotometric data at 30° from continuous variations and slope ratio methods show a 1:1 molar ratio of Fe to 8-quinolinol N-oxide in a pH range of 0.5-3.5, contrary to a 1:3 ratio reported by Murase (CA 49, 10786d). The complex was brownish green. Stability constant determination by the 2 methods gave log K = 3.28 and 3.63, resp. The absorption maximum was 510 mμ. In pH range 6.5-8.4, maximum was at 425-30 mμ, and in pH range 3.6-6.0, maximum were at 510 and 430 mμ; this indicates a mixture at pH 3.6-6.0.
After consulting a lot of data, we found that this compound(1127-45-3)Quality Control of 8-Hydroxyquinoline 1-oxide can be used in many types of reactions. And in most cases, this compound has more advantages.
Reference:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider