A 5L reaction vessel fitted with 500mL Dean and Stark apparatus is charged with 1.5kg helional in 750mL toluene and brought to gentle reflux. To this is added 570.78g diethylamine dissolved in 250mL toluene and added slowly and the mixture held at reflux until no more water collects in the trap about 375mL. The solution is cooled. To the helional-diethylamine enamine intermediate is added 38.63g copper (I) chloride and the solution is overhead stirred under a light pressure of oxygen.The mixture is stirred and monitored by TLC until it is judged to be fully oxidized (~2 hours). The organic solvent is then washed with aqueous acid to remove the amide moiety produced by enamine cleavage, leaving MDP2P in the solvent virtually free of any undesirable contaminates. The solvent is removed in vacuo at 40°C. The dried MDP2P is purified further by vacuum distillation (Vigreux column, length = 13cm, vacuum pressure = 0.99mbar, oil bath = 160°C, head temperature 109-110°C). After removing a small forerun there is obtained MDP2P (M= 178.19g/mol) as a clear colorless to slight yellow greenish liquid.
To a tared plastic bottle (with well sealing screw cap) add 2.5 liters very cold absolute anhydrous methanol and weigh (with cap). Add to this from a tared volumetric flask ca. 1500 ml (= ca. 1048.5 gm) very cold methylamine (dispensed from a cold steel cylinder; methyamine density=0.699;
boiling point is -6.3°C; pre-freeze the steel methylamine cylinder in the freezer or in an acetone- dry ice bath); for a double check on the numbers, note the exact volume of methylamine you used, and weigh the flask plus methylamine before adding to the bottle with the methanol in it. Put cap on, swirl around to dissolve the methylamine, and weigh the bottle again. Subtract bottle plus cap weight to get final solution weight. Final volume is assumed to be 2.5 liters (methanol) plus the noted volume of methylamine used (ca. 1.5 liters), i.e. ca. 4 liters. You now have a stock
solution with the following approximate concentration (do an exact calculation of your concentration using the exact volume of methylamine you actually used): 1 gm methylamine (0.032353 moles) in 3.81 ml solution. You will use this solution by volume (see next step). Keep the stock solution in the freezer at all times!
Add to a 5 liter steel-jacketed teflon hydrogenator:
1100 gm distilled ketone (ca. 6.18 moles)
802 gm methylamine solution (ca. 6.8 moles; for prep. see previous step)
6.2 gm PtO2 (Adam's catalyst)
1100 ml absolute methanol
Rinse the ketone remainder from the addition flask into the hydrogenator using some of the 1100 ml methanol. The PtO2 is first added to the methylamine solution and the methanol very cautiously (fire hazard!!) as follows: to the stirring cold (!) methylamine solution in a large beaker cautiously and in small increments add the PtO2 through a dry (!) wide funnel; make sure the PtO2 drops into the stirring vortex and mixes quickly with the methylamine solution; add almost all of the remainder of the 1100 ml methanol through the funnel to the beaker, carefully washing in the PtO2 residue adhering to the funnel; be aware that fire on the funnel at this point would immediately ignite the methanol methylamine solution below, so be careful and wear protective gear. Pour the methylamine-PtO2-methanol mixture into the hydrogenator; rinse the beaker once with the small remainder of absolute methanol and add this to the hydrogenator. Seal the bomb, flush 3x w. hydrogen, place under 75 psi hydrogen, and set, while stirring vigorously on a magnetic stirrer, in a bath of freshly boiled water (this reduces the induction period to a few minutes and initiates rapid hydrogen uptake). Following each uptake add more hydrogen until no more is being consumed (ca. 30-40 minutes) Let stir an additional 30-40 minutes under 75 psi to ensure complete reduction. Vent to air, dismantle hydrogenator, and filter the reaction mixture, washing out the hydrogenator and the PtO2 residue on the filter w. absolute methanol. Don't let the PtO2 go dry or it will ignite! Wash the PtO2 off the filter paper into a storage bottle with methanol; it can be reused and ultimately regenerated, but I have always used fresh PtO2. Remove the methanol from the recieving flask; remove last traces of methanol and methylamine under high vacuum. The 1200g freebase MDMA is subjected to vacuum distillation and salted by gassing.
To a tared plastic bottle (with well sealing screw cap) add 2.5 liters very cold absolute anhydrous methanol and weigh (with cap). Add to this from a tared volumetric flask ca. 1500 ml (= ca. 1048.5 gm) very cold methylamine (dispensed from a cold steel cylinder; methyamine density=0.699;
boiling point is -6.3°C; pre-freeze the steel methylamine cylinder in the freezer or in an acetone- dry ice bath); for a double check on the numbers, note the exact volume of methylamine you used, and weigh the flask plus methylamine before adding to the bottle with the methanol in it. Put cap on, swirl around to dissolve the methylamine, and weigh the bottle again. Subtract bottle plus cap weight to get final solution weight. Final volume is assumed to be 2.5 liters (methanol) plus the noted volume of methylamine used (ca. 1.5 liters), i.e. ca. 4 liters. You now have a stock
solution with the following approximate concentration (do an exact calculation of your concentration using the exact volume of methylamine you actually used): 1 gm methylamine (0.032353 moles) in 3.81 ml solution. You will use this solution by volume (see next step). Keep the stock solution in the freezer at all times!
Add to a 5 liter steel-jacketed teflon hydrogenator:
1100 gm distilled ketone (ca. 6.18 moles)
802 gm methylamine solution (ca. 6.8 moles; for prep. see previous step)
6.2 gm PtO2 (Adam's catalyst)
1100 ml absolute methanol
Rinse the ketone remainder from the addition flask into the hydrogenator using some of the 1100 ml methanol. The PtO2 is first added to the methylamine solution and the methanol very cautiously (fire hazard!!) as follows: to the stirring cold (!) methylamine solution in a large beaker cautiously and in small increments add the PtO2 through a dry (!) wide funnel; make sure the PtO2 drops into the stirring vortex and mixes quickly with the methylamine solution; add almost all of the remainder of the 1100 ml methanol through the funnel to the beaker, carefully washing in the PtO2 residue adhering to the funnel; be aware that fire on the funnel at this point would immediately ignite the methanol methylamine solution below, so be careful and wear protective gear. Pour the methylamine-PtO2-methanol mixture into the hydrogenator; rinse the beaker once with the small remainder of absolute methanol and add this to the hydrogenator. Seal the bomb, flush 3x w. hydrogen, place under 75 psi hydrogen, and set, while stirring vigorously on a magnetic stirrer, in a bath of freshly boiled water (this reduces the induction period to a few minutes and initiates rapid hydrogen uptake). Following each uptake add more hydrogen until no more is being consumed (ca. 30-40 minutes) Let stir an additional 30-40 minutes under 75 psi to ensure complete reduction. Vent to air, dismantle hydrogenator, and filter the reaction mixture, washing out the hydrogenator and the PtO2 residue on the filter w. absolute methanol. Don't let the PtO2 go dry or it will ignite! Wash the PtO2 off the filter paper into a storage bottle with methanol; it can be reused and ultimately regenerated, but I have always used fresh PtO2. Remove the methanol from the recieving flask; remove last traces of methanol and methylamine under high vacuum. The 1200g freebase MDMA is subjected to vacuum distillation and salted by gassing.