Abstract

This study investigated the use of copper(II) bromide as a brominating agent in a two-step synthetic pathway for the preparation of the cathinone analogues methcathinone, mephedrone and eutylone, as a result of pre-precursors and a clandestine document being seized by authorities in New Zealand. In the first step, propiophenone, 4'-methylpropiophenone and 3', 4'-(methylenedioxy)butyrophenone were brominated using copper(II) bromide, yielding the corresponding a-bromo intermediates: 2-bromopropiophenone , 2-bromo-4'methylpropiophenone and 2-bromo-3',4'(methylenedioxy) butyrophenone, with yields of 81%, 68% and 72%, respectively. The resulting intermediates were subsequently aminated to produce the target cathinone hydrochloride salts, with overall yields of 21% for methcathinone, 25% for mephedrone and 43% for eutylone, calculated over the two-step synthetic process from starting materials to final product. The findings demonstrate that copper(II) bromide is a viable brominating agent in this synthetic pathway, providing insight into an alternative bromination method relevant to both forensic and synthetic chemistry applications.