The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Dipole moments of some furfural derivatives》. Authors are Kova-lenko, K. N.; Minkin, V. I.; Nazarova, Z. N.; Kazachenko, D. V..The article about the compound:5-Iodo-2-furaldehydecas:2689-65-8,SMILESS:IC1=CC=C(O1)C=O).Quality Control of 5-Iodo-2-furaldehyde. Through the article, more information about this compound (cas:2689-65-8) is conveyed.
The following values of dipole moments (in D.) were determined from the dielec. data in C6H6 at 25°: furfural 3.56; 5-bromofurfural 3.37; 5-iodofurfural 3.29; 5-chiorofurfural 3.37; 5-nitrofurfural 3.46; 5-nitrofurfurylidene diacetate 4.26; the following values were found in dioxane: furfural 3.6, 5-iodofurrural 3.39. The results indicate that free rotation of the CHO group in furfural and its 5-halo derivatives is restricted and the mols. exist mainly in a conformation with the CHO-oxygen atom disposed toward the ring O atom.
There is still a lot of research devoted to this compound(SMILES：IC1=CC=C(O1)C=O)Quality Control of 5-Iodo-2-furaldehyde, and with the development of science, more effects of this compound(2689-65-8) can be discovered.
Reference:
1,8-Naphthyridine – Wikipedia,
1,8-Naphthyridine | C8H6N2 – PubChem