The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Separation of halogenated acetic and propionic acids by paper chromatography》. Authors are Chittum, John W.; Gustin, Thomas A.; McGuire, Robert L.; Sweeney, John T..The article about the compound:2,3-Dibromopropionic acidcas:600-05-5,SMILESS:O=C(O)C(Br)CBr).Computed Properties of C3H4Br2O2. Through the article, more information about this compound (cas:600-05-5) is conveyed.
cf. C.A. 46, 889i. Mixtures containing (1) AcOH, ClCH2CO2H, Cl2CHCO2H, and Cl3CCO2H and (2) AcOH, BrCH2CO2H, Br2CHCO2H, and Br3CCO2H were separated by the method of Reid and Lederer (C.A. 46, 1923a). Rf values are given for the above acids and certain halogenated propionic acids.
In addition to the literature in the link below, there is a lot of literature about this compound(2,3-Dibromopropionic acid)Computed Properties of C3H4Br2O2, illustrating the importance and wide applicability of this compound(600-05-5).
Reference:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem