189937-21-1Relevant articles and documents
New insights into bromination process: Effective preparation of Ambroxol
Xu, Jun-Hui,Ma, Yan-Qiong,Wei, Jian-Ping,Li, Fang-Mei,Peng, Xin-Hua
, p. 722 - 728 (2015)
Ambroxol used as an expectorant in treating respiratory diseases was effectively prepared with a total yield of 62 %, with o-toluidine as the feedstock via successive procedures of electrophilic bromination, acetylation, radical benzylic bromination, N-alkylation and hydrolysis processes. The addition of aqueous hydrogen peroxide could enhance the utilisation of liquid bromine in the electrophilic bromination of o-toluidine, avoiding the hazardous HBr generated as a by-product. In addition, liquid bromine promoted by MnO2 was used efficiently for the radical benzylic bromination of N-acetyl-N-(2,4-dibromo-6-methylphenyl)acetamide under mild conditions.