The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《New synthesis of the benzothiazole and benzoxazole rings》. Authors are Jenkins, Glenn L.; Knevel, Adelbert M.; Davis, Charles S..The article about the compound:2-Ethylbenzo[d]oxazolecas:6797-13-3,SMILESS:CCC1=NC2=CC=CC=C2O1).COA of Formula: C9H9NO. Through the article, more information about this compound (cas:6797-13-3) is conveyed.
HC(OEt)3 (37 g.), 22 g. 2-H2NC6H4SH, and 0.7 g. concentrated H2SO4 heated (oil bath) to 115-30° with distillation of EtOH, heating continued 1 hr. to 170-80° with distillation of 31 ml. EtOH, the mixture heated 45 min. at 175-85°, and the cooled product distilled in vacuo gave benzothiazole, C6H4.X.CR:N (I, X = S, R = H), b754 183°. Similarly were prepared the tabulated I in 75-86% yields (X, R, and b.p./mm. given): S, Me, 151°/15; S, Et, 132°/18; O, H, 182°/753; O, Me, 91°/18; O, Et, 129°/23.
In some applications, this compound(6797-13-3)COA of Formula: C9H9NO is unique.If you want to know more details about this compound, you can contact with the author or consult more relevant literature.
Reference:
Benzoxazole – Wikipedia,
Benzoxazole | C7H5NO – PubChem