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A Two-Step Protocol for Umpolung Functionalization of Ketones Via Enolonium Species
Published on: August 16, 2018
Identification of 2-(ethylamino)-1-(4-methylphenyl)-1-pentanone (4-MEAP), a New "Legal High" Sold by an Internet
Danielle Hamby1, Annessa Burnett, Michael Jablonsky
1Department of Justice Sciences, University of Alabama at Birmingham, 1201 University Blvd., Birmingham, AL.
Abstract:
Online vendors are offering a new legal high, 4-methylpentedrone (4-MPD). Information for potential users provided by internet vendors of 4-MPD includes incorrect structures and nonexistent CAS numbers. A sample of 4-MPD was obtained and analyzed using GC-MS, NMR, and LC-EIS. The fragmentation data from the GC-MS and LC-EIS produced an M-1 ion that suggested the molecular mass was 219 amu, rather than 205 amu as calculated for 4-methylpentedrone. The difference in molecular mass corresponded to the addition of a methyl group. Based on the mass and fragmentation pattern, two standards were synthesized, 2-(ethylamino)-1-(4-methylphenyl)-1-pentanone and 1-(4-methylphenyl)-2-(propylamino)-1-butanone. The synthesis involved bromination of the appropriate ketone followed by the reaction with ethylamine or propylamine. Based on the NMR data and unique fragmentation patterns produced by these molecules, the sample was identified as 2-(ethylamino)-1-(4-methylphenyl)-1-pentanone, not 4-methylpentedrone.
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