Author Topic: Os/BS AlHg MeAm Amination writeup  (Read 3659 times)

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RoundBottom

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Os/BS AlHg MeAm Amination writeup
« on: August 10, 2002, 09:37:00 AM »
Os/BS AlHg MeAm Amination

by RoundBottom (with much help and thanks to Chromic)

Reagents

(the first amount is the actual amount measured, the amounts in brackets are the desired/calculated amounts)

55.2g (53.4g) ketone [1]
66.9g (66.8g) MeAm [2]
39.6g (39.6g) 98% NaOH
423mL (420mL) MeOH
26.1g (26.7g) Al Foil [3]
141mg (150mg) HgCl2

230g KOH [4]
dH2O

Equipment

1000mL 1N RBF
allihn condenser
claissen adapter
them and adapter
1" egg bar
mantle and controller
cooling setup

Short Form:

mixed 66.8g MeAm in 67g dH2O
mixed 39.6g NaOH in 119g dH2O, cooled in ice bath
mixed 423mL MeOH, 26.1g Al foil, 140mg HgCl2 in RBF
slowly poured NaOH solution into MeAm solution, then added to RBF
added ketone to RBF
refluxed with mixing until slowed down and temp started dropping, then added heat to keep at ~65°C
strained unreacted foil
basified with KOH solution (230g 85% KOH, 469g dH2O)
extracted 1x 500mL, 1x 200mL toluene
washed toluene 3x 700mL dH2O, 1x 700mL brine
dried 10 minutes in 40g MgSO4
gassed and vacuum filtered 5x, cleaned in boiling acetone, vacuum filtered, dried
yield 50.99g

Procedure

Mixed 66.9g MeAm was with 67mL (67mL) dH2O.  Mixed 39.6g NaOH with 119g (119mL) dH2O, and cooled in ice bath. 

Set up equipment, started cooling, added stir bar.  Put 26.1g Al foil in RBF.  Added most of the 423mL MeOH to the RBF, saving about 50mL to wash out the ketone container.  About 140mg of HgCl2 was then added to the RBF and the whole flask was swirled to mix the HgCl2 into the MeOH. 

Once the MeOH started bubbling (about 5 minutes after the addition of the HgCl2), the cool NaOH solution was slowly poured into the MeAm solution.  The smell of MeAm gas was now very strong.  The basified MeAm solution, and the 55.2g ketone were then poured into the RBF.  The remaining MeOH was swirled in the ketone flask and added to the RBF, and the whole flask was swirled a few times to mix everything.

This reaction is nowhere near as exothermic as a Methyl Man Al/Hg Nitromethane.  The fact that 55g of ketone (~300mmol) can be comfortably converted in a 1L flask says it all.

Stirring was attempted, but the bar would not move, probably due to the Al foil weighing it down.  Different stirrers were tried, but to no avail.  During the reflux the solution was bubbling quite well, but was still diligently swirled a couple times every five minutes.  After the reflux subsided, the flask was swirled approximately every 15 minutes.  When a top layer of clear fluid started forming, that means it's time to swirl.

The temperature rose quickly to about 72°C with lots of foil floating on the top, and lots of bubbles were evolving, but it stayed in control.  This is with all the ketone added at once.  See below for a full temperature readout.

The reaction was left to run for 4.5 hours, and began to calm down after about 45 minutes from the addition of the ketone.  When it calms down a bit, prepare the basification solution (230g 85% KOH added to 469mL dH2O) to give it time to cool.  Heat was added to the RBF after about 75 minutes to get the temperature up to about 65°C.

Once the reaction is deemed finished, (there isn't really an indicator to look for, just when enough time has elapsed) strain/filter out any unreacted foil chunks.  In this case, a large amount was left, probably about 8g, if dry.  The foil in the strainer was rinsed with about 50mL dH2O which was added to the reaction contents in a 2L beaker.

The mixture was slowly basified by pouring the KOH solution into reaction contents, and was stirred on a stirrer for about 10 minutes.  Some bubbling was observed as any remaining foil was reduced.  The mixture was extracted with 1x 500mL, 1x 200mL fresh toluene by pouring the toluene into the beaker and continuing stirring.  After separating the extractions were combined.  The toluene started out clear, water-white, and after the extractions was slightly cloudy and slightly coloured. 

The combined toluene extracts were washed with 3x 700mL dH2O, 1x 700mL brine (saturated NaCl).  Most of the cloudiness cleared up after the washes.  The toluene was dried in 40g dried MgSO4 for 10 minutes. 

The toluene was then gassed, and filtered 4 times.  Even though the crystals were as white as has been ever seen, the crystals were put into some boiling acetone and filtered again.

Total yield after acetone cleaning: 51.1g (92.4% w/w)

Anyone want some Nitromethane?


Temperature Readout

T+       Temp (°C)
    0    24°C
+  10    58°C
+  15    71°C
+  20    72°C
+  30    70°C
+  40    69°C
+  50    68°C
+  85    64°C (external heat added)
+ 105    66°C
+ 115    67°C
+ 175    56°C (heat off)
+ 265    50°C



Notes
[1] made by buffered performic, double distilled, measured a hair under 44mL, had light pale green tint... used up remaining amount, so it was a bit over what was called for
[2] made by chromic's method, as written up on the Hive
[3] properly nuggetized
[4] not enough NaOH (needed 200g) was available to basify the mixture, so enough 85% KOH flakes were used to compensate

EDITS: added temp table, fixed 2 degrees symbols in main writeup.


i learned a thing or two from charlie dontcha know.

Chromic

  • Guest
Awesome write up!
« Reply #1 on: August 10, 2002, 09:40:00 PM »
Awesome write up, fantastic yields! I'm sure this made for a happy weekend.  :)

Switch those water washes to 5% NaOH washes, and I bet your yield should go up a notch more. Btw, I know you cooled that acetone in your freezer after boiling the mdma.hcl in acetone, but your writeup doesn't mention it.

Again: nice going! Keep up the good work and the good posts.  8)

PS. I've got a few liters of nitromethane too, what the fuck to do with it, eh?


Diggity

  • Guest
VL, Really? How do you turn it into MeAm (g)?
« Reply #3 on: August 12, 2002, 11:11:00 PM »
VL,

Really? How do you turn it into MeAm (g)?

& I'm, somethin of a phenom, 1 puff of da cron, I'm un-stopable.   
 

weedar

  • Guest
To Diggity
« Reply #4 on: August 13, 2002, 12:19:00 AM »
I think he was talking about Methyl Man's Al/Hg where they
use nitromethane and methylamine is produced in situ.

https://www.thevespiary.org/rhodium/Rhodium/chemistry/alhg-meno2.html


Or,possibly,he is talking about what PrimoPyro recently
discussed in Chemistry Discourse:

Post 343961 (missing)

(PrimoPyro: "Reduction of Nitroparrafins with Al/HCl", Chemistry Discourse)

based on

https://www.thevespiary.org/rhodium/Rhodium/chemistry/eleusis/methylamine27.html#Nitromethane



Weedar

I'm not sure about you guys,but I'm baking brownies!

Diggity

  • Guest
;)
« Reply #5 on: August 13, 2002, 06:42:00 AM »
Thanx for the links weedar  :)  

..reading..



& I'm, somethin of a phenom, 1 puff of da cron, I'm un-stopable.   
 

patrick

  • Guest
Simplified procedure
« Reply #6 on: August 16, 2002, 07:04:00 PM »
Thank you Roundbottom, your procedure is a must !!!

I have used some little simplification:

mixed 67gMeAm in 67g dH2O
mixed 40g NaOH in 119g dH2O, cooled in ice bath
mixed 423mL MeOH, 26.1g Al foil, 140mg HgCl2

> thickness of the Al same as american Reynold heavy duty

> in a 2l, 2 necks RBF, condensor in central neck

slowly poured NaOH solution into MeAm solution, then added to RBF

> in a sep funnel attached to 2nd neck

added ketone, with a little MeOH

> in a sep funnel attached to 2nd neck

> added hot water to the bath to speed up the reaction, reaction started extremely quickly, with a VERY strong reflux. This quick reaction would have been difficult to realize in a 1l RBF.

refluxed with mixing, reaction seems to be completed in 2 hours, leaved an other hour (total 3h)

> no problems for the mixing with an egg shape magnet

basified with NaOH solution (200g NaOH, 700g dH2O)

> basified in the same RBF, NaOH solution added through a sep funnel. Reaction was EXTREMELY exothermic, had to add it slowly. The reaction was leaved for half an hour in order to destroy all the remaining Al.

extracted 1x 500mL, 1x 200mL toluene
washed toluene 3x 700 ml 10% NaOH solution

dried 10 minutes in 40g MgSO4

gassed and vacuum filtered 2x, cleaned in cold acetone, vacuum filtered, dried

yield 56g


Yeepee !!!

PS:

Meam was bought at Aldrich
MDP2P was made by p-benzo Wacker

madprosr

  • Guest
why over-basify?
« Reply #7 on: May 05, 2003, 01:25:00 AM »
so swim ran this reduction on 20.6g light-yellow ketone in a 500ml flask. scaled everything down directly, the Al amalgamated in a minute, dripped in the ketone over 30min, refluxed vigorously for 30min more, stirred for 1.5h after that until room temperature.

then swim basified with 5g of NaOH (in solution) to pH 11. swim added 1.2g more NaOH which definetly gave pH 14. extracted 100ml, 5x 50ml toluene. washed, dried, gassed, filtered and scraped up 18g of dry 'sassy-smelling' mdma.hcl.

imho, RB's workup should call for about 15g NaOH in 230ml water, followed by the toluene extractions.

the purpose of the water is to increase the density of the alcoholic solution so the toluene will float.

please, if adding base past pH 14 increases your yeilds somehow then explain it to me. swim believes he gets 90% w/w instead of gram-for-gram  because he doesn't fractionate the ketone...

any pH over 12 is sufficient for extraction.

OcoteaCymbarum

  • Guest
Pre-mixing the MeAm sln and ketone
« Reply #8 on: July 25, 2003, 02:38:00 AM »
I was wondering if anyone gave a thought about this or tried?
Mix the MeAm Hcl in water with the NaOH sln. Add in the ketone in a little methanol and let them sit a while to form the iminine. How much time? I dont know anything about the kinetics of imine formation.
Then add this mix to the RBF containing the Al/Hg amalgam.

Would this reduce the amount of side product produced(mdp2Pol)?

Rhodium

  • Guest
Preforming Imine before reducing it with Al-Hg
« Reply #9 on: July 25, 2003, 05:21:00 AM »
That is a very good idea, but do not add more than 1 equivalent of NaOH to the MeNH2.HCl / MDP2P solution. You want to convert all the methylamine hydrochloride to the freebase, but you want to avoid keeping MDP2P in a strongly basic solution for an extended period of time (polymerization hazard). You also will need some good stirring, as I don't believe MDP2P will dissolve homogenously in a methanolic solution of MeNH2/NaCl/H2O.

El_Zorro

  • Guest
OcoteaCymbarum: Post 441479
« Reply #10 on: July 25, 2003, 08:55:00 AM »
OcoteaCymbarum:

Post 441479

(El_Zorro: "Chromics Al/Hg", Newbee Forum)



OcoteaCymbarum

  • Guest
Thanks guys
« Reply #11 on: July 25, 2003, 05:29:00 PM »
Thanks for that link, very informative.
I think I will try both and see the difference in yield if there is one. I'll also try to learn more about imine formation, kinetics, etc.
But thats only when my stepfather goes away, he's been preventing me from synthing since he decided to spend his whole month of vacation here!

technology

  • Guest
I have only just..
« Reply #12 on: August 14, 2003, 04:02:00 AM »
I have only just read this post, very good write up..

i thank those that have come before me..


all the best...

OcoteaCymbarum

  • Guest
You should try it
« Reply #13 on: August 14, 2003, 05:32:00 AM »
It works like a charm, with the same amount of foil, twice as more ketone!

I ran it with MeAm a la raffike and man it works good!

RoundBottom

  • Guest
addendum
« Reply #14 on: August 14, 2003, 10:27:00 AM »
i think some updates to this writeup are needed.  it's been working flawlessly for months now with a couple changes.

1.  do a full A/B after the extraction to toluene, it's worth it.
2.  do as chromic says, and use 5% NaOH washes, 1x 5% NaOH wash, then 1x dH2O wash is perfect.
3.  do titrate the freebase into salt (pH 3-4 with 10% HCl)... it's way more efficient in the long run, and there's no messing around with HCl gas.
4.  do recrystalize with isopropyl alcohol, expecially if you titrate.

this has been done at the 900mmol (160g ketone) level in a 3L flask, and returns between 145-149g (~90% w/w) of clean salt every time.

SWIM is intrigued with the idea of using much less MeAm.  can anyone confirm it's effectiveness?


xspikehead

  • Guest
MDP2P or P2P?
« Reply #15 on: August 15, 2003, 12:11:00 AM »
It sounds like the majority of you used MDP2P - anyone have any luck using P2P while affording similar yields?  Thanks.


technology

  • Guest
What about increasing the...
« Reply #17 on: August 15, 2003, 07:02:00 AM »
What about increasing the ketone even more? is it possible to increase the ketone to increase yeilds a bit more, but still maintaining the same amounts of Al foil and HgCL12.

Or will you be left with un reacted ketone?

Just a thought..

raffike

  • Guest
Better yet increase the amount of methylamine...
« Reply #18 on: August 15, 2003, 07:13:00 AM »
Better yet increase the amount of methylamine or run rx with thicker Al or keep temps lower.Slower reactions give higher yields.Raf has done Al/Hg in 50 minutes with yield of 55% w/w and has done another one in 3 hours with ~80% yields


technology

  • Guest
Even so..
« Reply #19 on: August 15, 2003, 07:33:00 AM »
Even so..

I gather most people are worried about time consumption with the MDMA synth.. But dont you think that its debateable whether longer periods of time will increase yeilds in rxn. We all know that you can control the rate of rxn speed by the addition of Nitromethane into the rxn contents..

I like the sound of increasing the methylamine and thicker foil.. this will perhaps result in a much stronger rxn but perhaps slower, therefore reacting all the ketone and making sure its run its full rxn..

Look, i am getting fucken lost with all these variations to diifer yeild.. i guess you just have to find one that works well for you and stick with it..

there are so many variables that can come into play.. chem purity perhaps being the most important, and not to mention the right amounts.. but what are the right amounts.. LOST IN THE REALM OF VARIATIONS"" OH help me GOD

bye the way loved your methylamine post raffike (great stuff) there needs to be more pics..