SYNTHESIS: A total of 30 mL butylamine was introduced under the surface of 33 mL concentrated HCl, and the mixture stripped of volatiles under vacuum. The resulting glassy solid was dissolved in 160 mL MeOH and treated with 7.2 g 3,4-methylenedioxyphenylacetone (see under MDMA for its preparation). To this there was added 50% NaOH dropwise until the pH was at about 6 as determined by the use of external dampened universal pH paper. The solution was vigorously stirred and 2.8 g sodium cyanoborohydride was added. Concentrated HCl was added as needed, to keep the pH constant at about 6. The addition required about two days, during which time the reaction mixture first became quite cottage-cheese like, and then finally thinned out again. All was dumped into 1 L H2O acidified with HCl, and extracted with 3×100 mL CH2Cl2. These extracts were combined, extracted with 2×100 mL dilute H2SO4, which was combined with the aqueous fraction above. This latter mixture was made basic with 25% NaOH, and extracted with 3×150 mL CH2Cl2. Evaporation of the solvent yielded 4.0 g of an amber oil which, on distillation at 90-100 °C at 0.15 mm/Hg, yielded 3.2 g of a white clear oil. This was dissolved in 20 mL IPA, neutralized with 30 drops of concentrated HCl, and the spontaneously formed crystals were diluted with sufficient anhydrous Et2O to allow easy filtration. After Et2O washing and air drying, there was obtained 2.8 g of 3,4-methylenedioxy-N-butylamphetamine hydrochloride (MDBU) as white crystals with a mp of 200-200.5 °C. Anal. (C14H22ClNO2) N.
DOSAGE: greater than 40 mg.
EXTENSIONS AND COMMENTARY: Straight chain homologues on the nitrogen atom of MDA longer than two carbons are probably not active. This butyl compound provoked no interest, and although the longer chain counterparts were made by the general sodium cyanoborohydride method (see under MDBZ), they were not tasted. All mouse assays that compared this homologous series showed a consistent decrease in action (anesthetic potency and motor activity) as the alkyl chain on the nitrogen atoms was lengthened.
This synthetic procedure, using the hydrochloride salt of the amine and sodium cyanoborohydride in methanol, seems to be quite general for ketone compounds related to 3,4-methylenedioxyphenylacetone. Not only were most of the MD-group of compounds discussed here made in this manner, but the use of phenylacetone (phenyl-2-propanone, P-2-P) itself appears to be equally effective. The reaction of butylamine hydrochloride in methanol, with phenyl-2-propanone and sodium cyanoborohydride at pH of 6, after distillation at 70-75 °C at 0.3 mm/Hg, produced N-butylamphetamine hydrochloride (23.4 g from 16.3 g P-2-P). And, in the same manner with ethylamine hydrochloride there was produced N-ethylamphetamine (22.4 g from 22.1 g P-2-P) and with methylamine hydrochloride there was produced N-methylamphetamine hydrochloride (24.6 g from 26.8 g P-2-P). The reaction with simple ammonia (as ammonium acetate) gives consistently poor yields in these reactions.