Influence of base on nitro-aldol (Henry) reaction products for alternative clandestine pathways

Australian clandestine drug laboratories are constantly utilising alternative methods to produce methamphetamine, in part as restrictions are placed by Government on, for example, chemicals such as phenyl-2-propanone (P2P) (in the early 1980s), or on pseudoephedrine-containing pharmaceuticals, from the mid-2000s. This paper discusses the nitro-aldol reaction occurring between nitroethane and benzaldehyde, which can be utilised in a number of differing routes, in the presence of different bases. The resulting products, namely phenyl-2-nitropropene (P2P pathway) and 2-nitro-1-phenyl-1-propanol (ephedrine pathway) are directly dependant on which base is used; as such, the base may be used to provide an indication of a possible manufacture pathway of methamphetamine at a clandestine laboratory.