GC–IRD methods for the identification of some tertiary amines related to MDMA

Maher, Hadir M.; Awad, Tamer; DeRuiter, Jack; Clark, C. Randall

doi:10.1016/j.forsciint.2010.02.022

« Previous Next »Forensic Science International
Volume 199, Issue 1 , Pages 18-28, 15 June 2010

GC–IRD methods for the identification of some tertiary amines related to MDMA

Hadir M. Maher
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Alexandria University, Alexandria 21521, Egypt
Tamer Awad
- Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, Suez Canal University, Ismaillia 41552, Egypt
- Division of Medicinal Chemistry, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
Jack DeRuiter
- Division of Medicinal Chemistry, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
C. Randall Clark
- Division of Medicinal Chemistry, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA
- Corresponding author at: Department of Pharmacal Sciences, Division of Medicinal Chemistry, Harrison School of Pharmacy, Auburn University, Auburn, AL 36849, USA. Tel.: +1 334 844 8326; fax: +1 334 844 8331.

Received 22 July 2009; received in revised form 5 February 2010; accepted 21 February 2010. published online 05 April 2010.

Abstract

Gas chromatography with infrared detection (GC–IRD) provides direct confirmatory data for the identification of the drug of abuse; 3,4-MDMA and its regioisomer; 2,3-MDMA, from a set of seven tertiary amines which have an isobaric or regioisomeric relationship with the MDMAs. These compounds include three ring substituted regioisomers of 2-dimethylamino-1-(methoxyphenyl)ethanone, two ring regioisomers of N,N-dimethyl-2-(methoxymethylphenyl)ethanamine in addition to N,N-dimethyl-2-(2,3- and 3,4-methylenedioxyphenyl)ethanamine. The major mass spectral fragments for each of these unique isomers occur at equivalent mass and all have equal molecular weight. Thus, gas chromatography with mass spectrometry detection (GC–MS) does not provide sufficient information for the confirmation of identity of any one of these isomers to the exclusion of the other compounds. The infrared spectra for these compounds allow for identification of any one of these amines. This differentiation is accomplished without the aid of chemical derivatization. The IR spectra served to divide the studied compounds into four groups depending on their absorption bands in the region 2700–3100cm⁻¹. Moreover, compounds with different ring substitution pattern within each group can be differentiated by several bands in the 700–1700cm⁻¹ region. These regioisomeric substances are well resolved by GC on Rtx-1 stationary phase and the vapor-phase infrared spectra clearly differentiate among this set of compounds.