Pozharskii, Alexander F.’s team published research in Organic Letters in 2019 | CAS: 696-59-3

2,5-Dimethoxytetrahydrofuran(cas: 696-59-3) is a member of ether. When aromatic ethers are exposed to halogen in the presence or absence of a catalyst, they undergo halogenation, such as bromination.Formula: C6H12O3

The author of 《Nucleophilic Substitution of Hydrogen Atom in Initially Inactivated Pyrrole Ring》 were Pozharskii, Alexander F.; Ozeryanskii, Valery A.; Dyablo, Olga V.; Pogosova, Olga G.; Borodkin, Gennady S.; Filarowski, Aleksander. And the article was published in Organic Letters in 2019. Formula: C6H12O3 The author mentioned the following in the article:

It has been found that 1-dialkylamino-8-(pyrrolyl-1)naphthalenes I[R = Me, Me; (CH2)4], upon treatment with an equimolar amount of HBF4 under ambient conditions, produce 1-dialkylammonium salts which are transformed into 7,7-dialkyl-7H-pyrrolo[1,2-a]perimidine-7-ium tetrafluoroborates II [R = Me, Me; (CH2)4, X =BF4], resp. The reaction proceeds in a highly selective manner and represents the first case of nucleophilic substitution of hydrogen in the initially inactivated pyrrole ring. The scope and limitations of the transformation, apparently operating due to the joint action of the “”proximity effect”” and proton catalysis, are outlined. In the part of experimental materials, we found many familiar compounds, such as 2,5-Dimethoxytetrahydrofuran(cas: 696-59-3Formula: C6H12O3)

2,5-Dimethoxytetrahydrofuran(cas: 696-59-3) is a member of ether. When aromatic ethers are exposed to halogen in the presence or absence of a catalyst, they undergo halogenation, such as bromination.Formula: C6H12O3

Referemce:
Tetrahydrofuran – Wikipedia,
Tetrahydrofuran | (CH2)3CH2O – PubChem