Mass spectrometric properties of N‐(2‐methoxybenzyl)‐2‐(2,4,6‐trimethoxyphenyl)ethanamine (2,4,6‐TMPEA‐NBOMe), a new representative of designer drugs of NBOMe series and derivatives thereof

A new compound in the NBOMe series of hallucinogenic phenethylamines, 2,4,6-TMPEA-NBOMe, was identified in the illicit drug market using multiple analytical techniques including GC/MS, high-resolution mass spectrometry, and NMR spectroscopy. The study describes the compound's fragmentation patterns under electron ionization, noting that a McLafferty rearrangement occurs despite an empirical rule that would predict otherwise, and that electron-donating methoxy groups favor this rearrangement. N-methyl and N-acyl derivatives did not show the rearrangement, while N-acyl derivatives exhibited it with charge retention on an alternative fragment. Analytical characteristics for detecting the compound in criminal seizures are provided.

Study at a glance

Abstract

Emergence of new psychoactive substances, hallucinogenic phenethylamines in particular, in illicit market is a serious threat to human health in global scale. We have detected and identified N‐(2‐methoxybenzyl)‐2‐(2,4,6‐trimethoxyphenyl)ethanamine (2,4,6‐TMPEA‐NBOMe), a new compound in NBOMe series. Identification was achieved by means of gas chromatography/mass spectrometry (GC/MS), including high‐resolution mass spectrometry with tandem experiments (GC/HRMS and GC/HRMS2), ultra‐high performance liquid chromatography/high‐resolution mass spectrometry with tandem experiments (UHPLC/HRMS and UHPLC/HRMS2), and 1H and 13C nuclear magnetic resonance spectroscopy. The peculiarities of fragmentation of the compound under electron ionization (EI) and collision‐induced dissociation were studied. Despite of the empirical rule denying migration of the hydrogen atom in McLafferty rearrangement to the benzene ring with substituents in the both ortho‐positions, it easily occurs for 2,4,6‐TMPEA‐NBOMe in EI conditions. We have noticed that electron‐donating substituents, e.g. methoxy groups in the both ortho‐positions and para‐positions favor the rearrangement. For specially synthesized N‐methyl and N‐acyl derivatives McLafferty rearrangement is not observed. N‐Acyl derivatives demonstrate McLafferty rearrangement, but the charge retains at the alternative fragment involving N‐acyl carbonyl group. We have also showed that the hydrogen atoms in 2,4,6‐trimethoxybenzene ring may be easily substituted for deuterium or for strong electrophiles like trifluoroacetyl. Analytical characteristics of 2,4,6‐TMPEA‐NBOMe and of some derivatives thereof which enable their determination in various criminal seizures are given. Copyright © 2016 John Wiley & Sons, Ltd.