The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Heterocyclic N-oxides. V. Substitution reactions on 8-hydroxyquinoline 1-oxide》. Authors are Ramaiah, Kommineni; Srinivasan, Vankipuram R..The article about the compound:8-Hydroxyquinoline 1-oxidecas:1127-45-3,SMILESS:OC1=CC=CC2=CC=C[N+]([O-])=C12).Recommanded Product: 8-Hydroxyquinoline 1-oxide. Through the article, more information about this compound (cas:1127-45-3) is conveyed.
Nitration and halogenation of 8-hydroxyquinoline 1-oxide (I) having N-oxide and phenolic OH groups, each capable of orienting electrophilic substitution in the different rings, was studied with a view to knowing the relative directive influence of these groups and to screen the compounds obtained for bacteriostatic and fungistatic activity. Halogenation afforded under usual conditions products by substitution only in the benzene ring. Thus, 1.5 ml. SO2Cl2 in 10 ml. CHCl3 was added dropwise to a stirred solution of 0.8 g. I in 10 ml. CHCl3 at <5° to yield 0.92 g. 5,7-dichloro-8-hydroxyquinoline 1-oxide (II) as H2O-insoluble fraction (aqueous solution A), m. 203-4° (HOAc). Deoxygenation of II with PCl3 afforded 5,7-dichloro-8-hydroxyquinoline, m. 176°. The aqueous solution (A) on cooling yielded 0.07 g. 5-chloro-8-hydroxyquinoline 1-oxide, m. 169-70°. Similarly, bromination of 0.8 g. I in 10 ml. HOAc with 1 ml. Br in 10 ml. HOAc yielded 1.42 g. of the dibromo compound, m. 198-200° (HOAc), which on deoxygenation yielded 5,7-dibromo-8-hydroxyquinoline, m. 195°. Nitration of 0.8 g. I in 10 ml. HOAc with 2 ml. fuming HNO3 (d. 1.5) initially at room temperature and then 1 hr. at 70-80° (water-bath) yielded 0.8 g. 5,7-dinitro-8-hydroxyquinoline 1-oxide (III), m. 213-14° (HOAc). Nitration of 0.8 g. I in 10 ml. HOAc with 0.7 ml. concentrated HNO3 (d. 1.42) at <20° for 1 hr. yielded 0.75 g. 5-nitro-8-hydroxyquinoline 1-oxide (IV), m. 191-3° (EtOH). The structure of III and IV were established through deoxygenation and comparison with the known 5-nitro and 5,7-dinitro-8-hydroxyquinolines. The phenolic hydroxyl exerts greater influence than the N-oxide function. The usual 5,7-disubstituted derivatives of 8-hydroxyquinoline, 5,7-dihalo- or the 5,7-dinitro compounds were resistant to N-oxidation either by 30% H2O2-HOAc or BzO2H. When you point to this article, it is believed that you are also very interested in this compound(1127-45-3)Recommanded Product: 8-Hydroxyquinoline 1-oxide and due to space limitations, I can only present the most important information.
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Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider