Stable isotope characterisation of 3,4-methylenedioxyphenyl-2-propanone and 3,4-methylenedioxyamphetamine prepared from piperonal.

Abstract

Stable isotopic ratios can provide information for illicit drug profiling. The research presented here investigated the variations in stable isotopic ratios of hydrogen (δ2 H), carbon (δ13 C), nitrogen (δ15 N) and oxygen (δ18 O) during the synthesis of MDP2P (3,4-methylenedioxyphenyl-2-propanone) and MDA (3,4-methylenedioxyamphetamine) prepared via the 'nitrostyrene' route. Samples of MDA and MDP2P were synthesised from two isotopically characterised starting materials, piperonal and nitroethane. The isotopic compositions of the nitrostyrene intermediate (3,4-methylenedioxyphenyl-2-nitropropene, MDP2NP) and products MDP2P and MDA were also measured by isotope ratio mass spectrometry. A significantly negative change occurred to δ2 H values during the production of MDP2NP, MDP2P and MDA, indicating a mechanism that favours inclusion or retention of 1 H over 2 H. This suggests that the δ2 H compositions of MDA/MDP2P prepared from piperonal will not provide information on the synthetic history. Minimal changes were observed in δ13 C composition during the synthesis of MDP2NP, MDP2P and MDA, and minimal δ15 N compositional changes occurred in MDP2NP and MDA. Progressing from piperonal to MDP2NP, a minimal change occurred to δ18 O composition. A variable change to δ18 O was observed from MDP2NP with one sample becoming more positive in δ18 O composition and two samples becoming more negative. Progressing from MDP2NP to MDA, a significant negative change occurred to δ18 O composition. The changes to stable isotopic ratios observed during the preparation of MDA and MDP2P from piperonal may prove useful when attempting to compare batch-to-batch variations between seizures and provide information with tactical intelligence applications.