Characterization of oxazolidine byproducts in methamphetamine laboratory analysis

Methamphetamine is a highly addictive drug and is becoming one of the most frequently abused drugs in the United States. Trace impurities and byproducts are often found in clandestinely produced drug samples and the occurrence of these impurities can provide valuable information on the method of synthesis. An oxazolidine compound is an example of a trace impurity sometimes found in methamphetamine samples when ephedrine or pseudoephedrine is used as the starting material. Oxazolidine compounds have been well established in the literature; however the research fails to provide key analytical reference data to aid in identification. Industry criteria require published reference data before these compounds can be identified and reported. Oxazolidine compounds were prepared from ephedrine and pseudoephedrine, and common aldehyde and ketone solvents (formaldehyde, acetaldehyde, benzaldehyde, acetone, phenyl-2-propanone (P2P) and methyl ethyl ketone (MEK)). The compounds were characterized using gas chromatography-mass spectrometry (GC-MS), nuclear magnetic resonance (NMR) and infrared (IR) spectrophotometry. The chemical structures of these compounds are given and their analytical data are consistent with the impurities seen in casework.