Test purchase, identification and synthesis of 2-amino-1-(4-bromo-2, 5-dimethoxyphenyl)ethan-1-one (bk-2C-B).
Drug testing and analysis – June 01, 2015
Source: PubMed
Summary
A new psychoactive substance, bk-2C-B, a beta keto-phenethylamine related to 2C-B and cathinones, is being sold online. Scientists successfully acquired and identified this compound using advanced forensic techniques. They also achieved its synthesis, creating vital reference material. Crucially, refined analytical methods were developed to accurately detect bk-2C-B without confusion from potential breakdown products, offering robust tools for its identification.
Abstract
2-Amino-1-(4-bromo-2,5-dimethoxyphenyl)ethan-1-one (bk-2C-B) has been recently offered for purchase by a variety of Internet retailers. This substance may be considered a cathinone analogue of the phenethylamine 2-(4-bromo-2,5-dimethoxyphenyl)ethan-1-amine (2C-B) which suggests that it may have psychoactive effects in humans. A test purchase of bk-2C-B was carried out and its identity was confirmed by a range of analytical techniques including nuclear magnetic resonance spectroscopy, gas and liquid chromatography, and high-resolution mass spectrometry. Confirmation was also obtained from the synthesis of bk-2C-B based on the implementation of the Delépine reaction in which the α-brominated intermediate was reacted with hexamethylenetetramine to afford the primary amine. Analysis of underivatized bk-2C-B by gas chromatography-mass spectrometry (GC-MS) showed that there was potential for artificial formation of 1-(4-bromo-2,5-dimethoxyphenyl)ethanone and a pyrazine dimer, these substances were not detected when employing liquid chromatographic analysis. Ion chromatography and X-ray crystallography analysis confirmed that the purchased bk-2C-B consisted of a hydrochloride and hydrobromide salt mixture, which indicated that it might have been prepared by the hexamethylenetetramine route followed by hydrochloric acid hydrolysis of the quaternary ammonium salt. X-ray crystallography also revealed that the purchased (mixed HCl/HBr salt) and synthesized bk-2C-B (HCl salt) exists as polymorphs.