ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7

Published monthly
 

New insights into bromination process: effective preparation of Ambroxol

Jun-Hui Xu, Yan-Qiong Ma, Jian-Ping Wei, Fang-Mei Li, and Xin-Hua Peng

School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China

 

E-mail: xhpeng@mail.njust.edu.cn

Abstract: 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.

Keywords: Ambroxol – electrophilic bromination – radical benzylic bromination – total synthesis

Full paper is available at www.springerlink.com.

DOI: 10.1515/chempap-2015-0077

 

Chemical Papers 69 (5) 722–728 (2015)

Tuesday, August 03, 2021

IMPACT FACTOR 2020
2.097
SCImago Journal Rank 2020
0.344
SEARCH
Advanced
VOLUMES
XXVIII. International Conference on Coordination and Bioinorganic Chemistry
© 2021 Chemical Papers