The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Some properties of 5-halofurfurals》. Authors are Nazarova, Z. N..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 derivatives of 5-halofurfurals are reported: 5-iodofurfural thiosemicarbazone, m. 162-3°, decompose 165°; 5-Br analog, decompose 196-7°; furfural thiosemicarbazone, m. 153-4°, decompose 180°; 5-bromofurfural 2,4-dinitrophenylhydrazone, m. 204-5°; 5-iodo analog, m. 210-11°; 5-iodofurfural NaHSO3 adduct, m. 220°; 5-Br analog, plates. Solubility: 5-Bromofurfural, in H2O, 20°, 0.5, g./100ml.; 100°, 2.5; in EtOH, 20°, 5.0; 78°, 120.0; in (CH2Cl)2, 20°, 3.7; 83°, over 360.0. 5-Iodofurfural, resp., 0°, 0.5; 3.0°, 40.0; 10.0°, over 360.0.
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