SYNTHESIS: The Grignard reagent of butyl bromide was prepared in anhydrous Et2O by the dropwise addition of 68 g n-butyl bromide to a well-stirred suspension of 14 g magnesium turnings in 500 mL anhydrous Et2O. When the exothermic reaction had stopped, there was added a solution of 60 g piperonal in about 100 mL Et2O, over the course of 1 h. After the exothermic addition was complete, the reaction mixture was held at reflux for several h, then cooled and decomposed by the addition of dilute HCl. The phases were separated, and the aqueous phase extracted with 2×75 mL CH2Cl2. The organics were combined and gave, after the removal of the solvents under vacuum, 84 g of 1-hydroxy-1-(3,4-methylenedioxyphenyl)pentane as a yellow liquid. This was used in the following dehydration step without further purification.
A mixture of 52 g of the crude 1-hydroxy-1-(3,4-methylenedioxyphenyl)pentane and 2 g powdered KHSO4 was heated with a flame until there was no more apparent generation of H2O. The resulting dark, fluid oil was distilled at 100-110 °C at 0.3 mm/Hg to give 29.5 g of 1-(3,4-methylenedioxyphenyl)-1-pentene as a light yellow liquid. This was employed in the following oxidation step without further purification.
To 120 mL of 90% formic acid there was added, with good stirring, 15 mL H2O, followed by 23 mL of 35% H2O2 To this mixture, cooled with an external ice bath, there was added a solution of 24 g crude 1-(3,4-methylenedioxyphenyl)-1-pentene in 120 mL acetone at a rate slow enough to keep the internal temperature from exceeding 35 °C. At the end of the addition, the temperature was brought up to 45 °C by heating briefly on the steam bath, and then the reaction mixture was allowed to stand and stir at ambient temperature for several h. All volatiles were removed under vacuum, with a bath temperature maintained at 45 °C. The residue was dissolved in 30 mL MeOH, then there was added 200 mL 15% H2SO4 and the mixture held on the steam bath for 1.5 h. There was then added an additional 300 mL H2O, and this was extracted with 2×250 mL of a petroleum ether/EtOAc (5:1) mixture. The extracts were pooled, and the solvents removed under vacuum to give a residue that was distilled at 115-120 °C at 0.3 mm/Hg. This light yellow liquid weighed 13.5 g and was substantially pure 1-(3,4-methylenedioxyphenyl)-2-pentanone by TLC.
To 5.0 g of aluminum foil cut into 1 inch squares, there was added a solution of 150 mg HgCl2 in 200 mL H2O. The mixture was heated briefly until there were clear signs of active amalgamation, such as fine bubbling for the aluminum surfaces and the beginning of the formation of a gray, amorphous solid phase. The HgCl2 solution was decanted off and the aluminum was washed with 2×200 mL additional H2O. After shaking as dry as possible, there was added, in sequence and with good swirling agitation between each addition, 10 g methylamine hydrochloride in 10 mL H2O, 27 mL IPA, 22 mL of 25% NaOH, 5.0 g 1-(3,4-methylenedioxyphenyl)-2-pentanone, and finally an additional 50 mL IPA. The mixture was heated on the steam bath periodically to maintain the reaction rate at a vigorous boil. When all of the aluminum had been consumed, the cooled mixture was filtered and the solids washed with MeOH. The combined filtrate and washings were stripped of solvent under vacuum. The residue was dissolved in dilute H2SO4 and washed with 2×75 mL CH2Cl2. After making basic again with 25% NaOH, this was extracted with 2×100 mL CH2Cl2, and the pooled extracts were stripped of solvent under vacuum. The residue was distilled at 105-110 °C at 0.3 mm/Hg to give 2.7 g of a colorless liquid. This was dissolved in 15 mL IPA, neutralized with concentrated HCl, and diluted with 75 mL anhydrous Et2O which allowed a delayed appearance of a fine white crystal. This was removed by filtration, Et2O washed, and air dried to give 2.45 g 2-aminomethyl-1-(3,4-methylenedioxyphenyl)pentane hydrochloride (METHYL-K) as a white product with a mp of 155-156 °C. Anal. (C13H20ClNO2) C,H.
DOSAGE: greater than 100 mg.
QUALITATIVE COMMENTS: (with 100 mg) There were no effects. I was busy and totally wound up and didn’t sleep until 3 AM, but this was probably unrelated to the Me-K.
EXTENSIONS AND COMMENTARY: The well appears to be running dry, with a pentane chain as a basic skeleton. METHYL-J, at this level, was already showing a number of hints and clues, largely physical such as coldness in the feet and a slight mastoidal pressure, that activity was right around the corner. But METHYL-K gave no such hints. The unmethylated homologue, 2-amino-1-(3,4-methylenedioxyphenyl)pentane (K), was also made, by the reductive amination of 1-(3,4-methylene-dioxyphenyl)-2-pentanone with ammonium acetate and sodium cyanoborohydride in methanol. It was a white crystalline solid, mp 202-203 °C, but is given here in the comments only, as its human assaying had never even been initiated. Anal. (C12H18ClNO2) C,H. The N-ethyl homologue, 2-ethylamino-1-(3,4-methylene-dioxyphenyl)pentane (ETHYL-K), is entered with its own recipe, on the other hand, since testing had been started with it.
And the longest chain that has been explored in this Muni Metro series is the six-carbon hexyl chain which is, quite logically, the L-series, sort of the end of the Taraval line (see under METHYL-J for an explanation). The central compound for all the L-compounds was the ketone 1-(3,4-methylenedioxyphenyl)-2-hexanone, which was prepared by the Grignard reagent of (n)-amyl bromide with piperonal to give 1-hydroxy-1-(3,4-methylenedioxyphenyl)hexane, dehydration of this with potassium bisulfate to the olefin, and oxidation of this with hydrogen peroxide and formic acid to the L-ketone which was an orange-colored liquid with a bp of 125-135 °C at 0.3 mm/Hg. This ketone was reductively aminated with ammonium acetate and sodium cyanoborohydride in methanol to produce 2-amino-1-(3,4-methylenedioxyphenyl)hexane hydrochloride (L) as a white crystalline product with a mp of 157-158 °C. Anal. (C13H20ClNO2) C,H. And this ketone was reductively aminated with methylamine hydrochloride and amalgamated aluminum in isopropanol to produce 2-methylamino-1-(3,4-methylenedioxyphenyl)hexane hydrochloride (METHYL-L) as a white crystalline product with a mp of 139-141 °C. Anal. (C14H22ClNO2) C,H. The reduction of this ketone in a similar manner with ethylamine hydrochloride produced 2-ethylamino-1-(3,4-methylenedioxyphenyl)hexane (ETHYL-L). None of this series has yet been explored either as psychedelic or entactogenic materials.