Identification and structural elucidation of 2,6-dichloro-3-fluoroetomidate: A new psychoactive substance in e-liquids.

The increasing prevalence of electronic cigarettes (e-cigarettes) has raised significant concerns regarding their safety and potential for abuse. This study, for the first time, reports the identification of a novel halogenated etomidate analogue (2,6-dichloro-3-fluoroetomidate) in seized e-liquids. Unlike previously reported modifications on the ester sidechain, this compound uniquely features three halogen atoms (2,6-chlorine and 3-fluorine) on the benzene ring, representing a new frontier in structural diversification of psychoactive substances. We characterized its structure using GC-MS, UHPLC-QTRAP-MS/MS, NMR, and FTIR, confirming it through de novo synthesis. By providing a comprehensive analytical database for this compound, our findings enable forensic laboratories to rapidly distinguish it from common regioisomers. Computational toxicology indicates a high risk of neurotoxicity, underscoring the urgency for regulatory scrutiny. This study provides a systematic analytical characterization to assist forensic workers in identifying similar substances.