The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Bromomethylation of aromatic compounds》. Authors are Nazarov, I. N.; Semenovskii, A. V..The article about the compound:1-(Bromomethyl)-4-ethylbenzenecas:57825-30-6,SMILESS:CCC1=CC=C(CBr)C=C1).Synthetic Route of C9H11Br. Through the article, more information about this compound (cas:57825-30-6) is conveyed.
Passage of HBr into 150 ml. MePh, 15 g. paraformaldehyde, 8.5 g. ZnCl2, and a little P 1 hr. at 50° gave after washing with NaHCO3 and H2O, 58% mixed MeC6H4CH2Br isomers (I), b10 82-90°, and some diaryl derivatives b13 145-50°. Passage of HBr into 150 ml. CCl4, 15 g. paraformaldehyde, and 10 g. ZnCl2 with a little P for 35 min. and dropwise addition of 53 g. EtPh at 50° in a continuous stream of HBr over 1.3 hrs. similarly gave 48.3% mixed EtC6H4CH2Br (II), b7.5 96-100°. Passage of HBr 6 hrs. into 90 ml. concentrated HBr, 70 g. MePh, 30 g. paraformaldehyde, and a little P, followed by 19 hrs. at 50° gave, after washing, 71.3% mixed MeC6H4CH2Br, b23 112-20°; similarly, EtPh gave 85% mixed EtC6H4CH2Br, b10 101-4°, while iso-PrPh gave 78% mixed iso-PrC6H4CH2Br (III), b20 126-30°. Hydrolysis of I gave mixed o- and p-MeC6H4CH2OH, b12 106-10°; II gave the corresponding Et analogs, b12 120-4° and III gave mixed iso-Pr analogs, b12 121-5°. The hydrolyses were run with chalk in hot H2O 24 hrs. Oxidation of the alcs. with CrO3 gave mixtures of o- and p-C6H4(CO2H)2; oxidation with 10% HNO3 in an autoclave at 200° gave the same products, in which the p-isomers predominated.
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Reference:
Quinoxaline – Wikipedia,
Quinoxaline | C8H6N2 | ChemSpider