δ13C and δ13H isotope ratios in amphetamine synthesized from benzaldehyde and nitroethane

Previous work in these laboratories and by Butzenlechner et al. and Culp et al. has demonstrated that the δ2H isotope value of industrial benzaldehyde produced by the catalytic oxidation of toluene is profoundly positive, usually in the range +300% to +500%. Synthetic routes leading to amphetamine, methylamphetamine or their precursors and commencing with such benzaldehyde may be expected to exhibit unusually positive δ2H values. Results are presented for δ13C and δ2H isotope values of 1-phenyl-2-nitropropene synthesized from an industrial source of benzaldehyde, having a positive δ2H isotope value, by a Knoevenagel condensation with nitroethane. Results are also presented for δ13C and δ2H isotope values for amphetamine prepared from the resulting 1-phenyl-2-nitropropene. The values obtained were compared with δ13C and δ2H isotope values obtained for an amphetamine sample prepared using a synthetic route that did not involve benzaldehyde. Finally, results are presented for samples of benzaldehyde, 1-phenyl-2-nitropropene and amphetamine that had been seized at a clandestine amphetamine laboratory.