Although NMPEA is available commercially, it may be synthesized by various methods. An early synthesis reported by Carothers and co-workers involved conversion of phenethylamine to its "p"-toluenesulfonamide, followed by "N"-methylation using methyl iodide, then hydrolysis of the sulfonamide. A more recent method, similar in principle, and used for making NMPEA radio-labeled with 14C in the N-methyl group, started with the conversion of phenethylamine to its trifluoroacetamide. This was N-methylated (in this particular case using 14C – labeled methyl iodide), and then the amide hydrolyzed.