Author Topic: For the vindication of Eleusis - Methylamine  (Read 56766 times)

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armageddon

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qualitative analysis
« Reply #120 on: August 06, 2004, 09:20:00 AM »
THX again Lugh!  :P

According to the nitrous acid test, secondary alipathic amines should give a yellow colouration without gas evolution upon treating a cooled solution of said amine  hydrochloride with aequous NaNO2 solution - in contrast to primary alipathic amines, which give vigorous gas evolution when said nitrite solution is added...

...and when testing 2ml's of my gassed MeAm/MeOH solution, there was vigorous gas evolution and no yellow colouration after rxn had subsided (the smell reminded me of pool supply stores BTW...  ;) )

This means no dimethylamine was formed when using the "IG-Farben" patent! (at least nothing to bother with  :) !)

Now when someone tells me how to differentiate between ammonia and amines, I'll be happy!!  :P

Greetz A


DoctorFeelgood

  • Guest
Foolproof methylamine synthesis
« Reply #121 on: August 06, 2004, 03:37:00 PM »
reading cubliums post yesterday, made me post this synthesis, which is easy and hard to fuck up. of course this might be nothing new to you, but as one could read, buying meam is a very bad idea. maybe one wants to look at the following procedure (thanx to ... for his help):

Chemicals needed:
Hexamine (easy to get,used e.g. in cheese manufacturing)
H2O
Muriatic Acid
Icecold Ethanol & Acetone

Note:      
Molar ratio Hexamine : Muriatic Acid = 1 : 4   

Equipment:   
rbf (min. 1l)
heating/stiring combo + eggshaped magnetic stirbar
liebig condenser + cooling setup
vertical vacuumadapter with stopper on top
hose attached to vacuumoutlet, leading e.g into toilette
buchner filter

Add in THIS order: (depends on your available flasksize)

(Version1)   
600g Hexamine + 400g H2O + 2100 ml Muriatic Acid    or

(Version2)    
200g Hexamine + 133g H2O + 700ml Muriatic Acid   or   

(Version3)   
128g Hexamine + 85g H2O + 450ml Muriatic Acid      

Note: you must add the water before adding the HCl, or Ammoniumchlorid will separate immediately in your flask, lowering the yield.

Step1:

Set up for reflux, place a tube from the vacuumadapter on top of the condenser down the sewer (ie toilet) so that the smells won’t be a problem.  Slowly heat e.g. on a steam bath (flask in a pot full of water) until the flask temp is around 100C.  If you heat too fast, the exothermic reaction will take off and heat up to 110C which isn’t a problem, just heat slowly. Then keep stiring at around 100C for 6 hours.

Step2:
Then change setup for distillation.  Distil half of the liquid away and cool to room temp.
This crashes out the ammonium chloride.  When cool, vacuum filter (can’t be done without a buchner filter) the solution and eventually save the ammoniumchlorid for further use.

Step3:
Then distill the filtrate (at atmospheric pressure) until the flask liquid temperature reached 150-160C. Immediatly pour the flask liquid into a sealable container.  When cool, the methylamine.hcl will solidify.

Vacuum filter the solid with your buchner, forget washing the crystals with chloroform or acetone - its a waste of time.  Wash the crystals (while in the buchner) with icecold ethanol.  Suck some air through the buchner filter to remove some residual ethanol and place wet crystals in a sealed container.  You can now use these filtered crystals as is if you like (but make sure you allow for the extra weight due to the alcohol, or dry them on a tissue for a couple of minutes.
The ethanol wash does take some methylamine.hcl with it, but it also takes the dimethyl and trimethyl crap as well.  You can distill off the ethanol, heat again and get a second – of course smaller – amount of meam.hcl .

Molar yield should be above 80%.

This is really easy, i did it several times and never failed . so don't be stupid, buy some methylamine from a chem supplier - and get busted!

greetings :)

Organikum

  • Guest
Dr Feelgood, thanks! You show again how one...
« Reply #122 on: August 06, 2004, 08:08:00 PM »
Dr Feelgood, thanks! You show again how one single idiot can destroy a whole thread easily.

Dumbass!
80% molar yield? Not only dumbass but either incompetent or a liar too.

fuck you.
ORG


psytech

  • Guest
haha dr
« Reply #123 on: August 06, 2004, 08:30:00 PM »

armageddon

  • Guest
well
« Reply #124 on: August 06, 2004, 09:24:00 PM »
You can distill off the ethanol, heat again and get a second – of course smaller – amount of meam.hcl

Yup - And if you use this "smaller amount" and process it further, you indeed will end up with a 8% molar yield of pure methylamine hydrochloride, which upon gassing it into ice-cold MeOH would result in 6% being taken up maybe - but your 80% yield is in no way comparable with others, as it tells us the yield of NH4Cl/CH3NH3Cl mixture you obtained...


I get the impression that the standard hex/HCl method evolves apparently lots of toxic fumes - at least up to date, no bee using the hex/HCl method was able to realize the difference between this patented procedure and theirs, and many try to sell their alcohol-less methods as being of more advantage...
Must be some nasty stuff these folks are breathing!  ;D


...BTW are the 80% molar yield calculated from hexamine?? With the equation 1 Hexamine + HCl -> 6 HCHO + 4 NH4Cl, this makes little sense! When you divide your 80% through 4, you will get 20% yield calculated from the NH4Cl you used - more realistic if your product was indeed only methylamine hydrochloride - which I seriously doubt...

(really sad)


Oh, and you can as well use the following procedures, as long as you don't post about it in this "methylamine from hex WITH alcohol"-thread...

https://www.thevespiary.org/rhodium/Rhodium/chemistry/methylamine.chemhack.html


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


https://www.thevespiary.org/rhodium/Rhodium/chemistry/eleusis/zwit.menh2.html


https://www.thevespiary.org/rhodium/Rhodium/chemistry/methylamine.html


https://www.thevespiary.org/rhodium/Rhodium/chemistry/methylamine.acetamide.html


https://www.thevespiary.org/rhodium/Rhodium/chemistry/methylamine.pdc.html



(couldn't resist)  :P


Greetz A


armageddon

  • Guest
please..
« Reply #125 on: August 11, 2004, 12:16:00 AM »
To all doubting bees and especially Abacus: if you really want to discuss any differences between this procedure and the "Vogel's" standard procedure in public, you should consider that I never wanted to accuse anyone using the Vogel's method, nor did I say it wouldn't work for making methylamine suited for a "Osmium style" Al/Hg reductive amination of certain ketones! I merely think that the talked-about patent has its own advantages, and in my opinion the patented procedure is one of the easiest ways for making pure methylamine I ever saw. And to give proof of this, I tried to work out a procedure that challenges the claimed advantages (low rxn temp, no overalkylation, no gas evolution). In no way did I claim it being the perfect way of making methylamine. I even miscalculated the ratios of reactands, and used an excess of formaldehyde, in case you didn't notice. And evidently, still no overalkylation happened... guess why?

I just don't understand why the fact that there might be another usable method repeatedly results in the belief that I would want to offend anyone with liking it..

And if it was of interest to me, I would've opened a new thread about the advantages of the Vogel's procedure time ago - believe me!

Post 310000

(Rhodium: "Everybody at the Hive always wait for someone ...", Chemistry Discourse)
 ;)
(BTW I'm almost sure that the reaction time could be shortened by using a vigreux, due to higher rxn temp. while still allowing for a sharp separation of educt and product..)

A


biffman

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How can you not love this thread?
« Reply #126 on: August 11, 2004, 04:43:00 AM »
First off, thanks lugh for that link for the ID tests.  Since I no longer have access to a USP I have been waiting for a compound ID reference site, so it is much appreciated.
 And thanks for hanging in there armageddon now that the bitch slap with abolt seems to have gone by the wayside (for the moment anyways).
  Personally SWIM never had a problem with Vogel's (or obtaining MeAm for that matter previously) but caution is always a good plan and SWIM thought that the exploration of other avenues is not only warranted but also fun.
  When SWIM has an endless supply of Ammonium Chloride as well as formaldehyde certain other considerations come into play, but none are too important if you don't have to worry about precursor depletion.  Experiment is not only king but also entertaining.
  Sassy supply however is another matter nowdays.
  Thanks for all the input everyone.

placebo

  • Guest
New Hex method. Thoughts...
« Reply #127 on: August 11, 2004, 05:25:00 AM »
New Hex method.
Thoughts...
4:1 molar ratio of HCL to Hexamine
4 mol HCl + 1 mol hexamine = 6 mol form and 4 mol NH4Cl = 1.5:1
Standard Vogel procedure is -
500gm 35% form  = 6.16 mol
250gm nh4cl     = 4.67 mol = 1.32:1
Therefore: for 4 mol of NH4Cl (x1.32) there should be 5.28 mol of formaldehyde. So for the 6 mol of fomaldehyde, the NH4Cl should be 4.55 mol.
New Org Patent ratio is -
"17 parts of 40% formaldehyde, 7 parts of 96% alcohol and 8 parts of ammoniumchloride"
170gm 40% form = 2.26 mol
80gm NH4Cl     = 1.50 mol = 1.51:1
70gm EtOH      =
As stated above, Hex and HCl gives us 1.5:1 already, 0.2 mol more then Vogel.
Why add the extra NH4Cl and why the extra water?
Surely the ratio as stated in the patent is by mol not weight, but Org stressed it was by weight. Should it be...
1278gm 40% form = 17 mol
427gm NH4Cl     =  8 mol = 2.13:1
322gm EtOH      =  7 mol
This would be different to the Vogel procedure in that there is an even larger excess of formaldehyde:NH4Cl to drive the reaction faster while having the ethanol to control DiMeam production.
This makes more sense, it also means that by adding more NH4Cl, surely you are defeating the purpose of the patent. As I understand the formaldehyde must be in excess to drive the reaction. If one were to have it in 1:1 ratio, nothing would happen?

How much NH4Cl should be recovered?

Some bee performed the reaction at these ratios following DBD's and Org's example...

Methylamine...
140gm Hexamine x 5 = 700
42gm  NH4Cl    x 5 = 210   (Org 28gm)
170gm EtOH     x 5 = 850   (Org 140gm)
420gm 35% HCl  x 5 = 2100

The hexamine, EtOH and NH4Cl were added to a RBF, followed by the HCl. Heat and mag-stirring was applied on a mantle. It was then refluxed for 3 hours. STP distillation was started and ethyl formate collected, first at 67c and then lowering to 40c (Therefore despite 3 hour reflux, ethyl formate was only just being produced) and slowly rising again until the water was coming over. The heat was turned up and water was distilled until volume reduced by half. Then the flask was cooled to room temperature and the solids were filtered (~600gm NH4Cl recovered- ~11mol). The water in the remaining mixture was then vacuum distilled .......methylamine is still being worked up.
Results to follow.
It is also noted that it is not faster.
It is also noted that any hex->Meam procedure is a pain in the ass compared to Vogels form/NH4Cl procedure which is easier, faster, cleaner alas the bee has no formaldehyde.


armageddon

  • Guest
nope - parts by weight
« Reply #128 on: August 11, 2004, 07:27:00 AM »
As I understand the formaldehyde must be in excess to drive the reaction. If one were to have it in 1:1 ratio, nothing would happen

That's puzzling, because I don't think formaldehyde has to be present in larger excess - why do you think a 1:1 ratio would result in nada? I would rather guess that with the Vogel's method, a healthy excess of HCHO is necessary to get things going, whereas with alcohol, the LeChtelier principle accomplishes that, through pushing the (ever-present) equilibrium between unreacted formaldehyde/ammoniumchloride/alcohol->reacted methylamine/formic acid/ethylformate to the right..

And the patent says: "17 parts by weight of 40% formaldehyde solution, 8 parts by weight ammonium chloride and 7 parts by weight 96% alcohol" ("Gewichtsteile" is parts by weight) - so Orgy was absolutely right with his proportions, and the patent uses exactly the same amounts like the Vogel's method (0.01 mol difference  ;) )...

Greetz A


placebo

  • Guest
That's fine if it's by weight, I just worked...
« Reply #129 on: August 11, 2004, 07:34:00 AM »
That's fine if it's by weight, I just worked out both weight and mol for my own understanding. I don't speak german. :)
But it aint the same ratio as Vogel as you can see.
My point is it has an even higher ratio of formaldehyde then vogel.
Secondly, by using hex instead of form/NH4Cl you get the exact ratio as the patent suggests, so why add NH4Cl?
If you add NH4Cl then you are defeating the purpose of the patent.
Are you not?


That's puzzling, because I don't think formaldehyde has to present in larger excess - why do you do a 1:1 ratio would result in nada?



If that were the case, why is it always done?
I guess you don't understand this reaction as well as you think, despite your rants. Not to say I do, but I've read a shitload on it and that is my understanding.




armageddon

  • Guest
really
« Reply #130 on: August 11, 2004, 07:51:00 AM »
I guess you don't understand this reaction as well as you think, despite your rants

I guess you are just about to start becoming insultive... ;)

...do YOU understand exactly why there obviously has to be an excess of formaldehyde? My guess would be that Vogels method uses an excess to be able to start things - the patent inventors just copied these ratios (common sense back in those those days) without questioning them, as they were approved to work fine...

On the other hand - they postulated the following overall reaction scheme:

      2 HCOH + NH4Cl + C2H5OH ---> CH3NH2*HCl + H2O + HCOOC2H5

Explains the amount of formaldehyde used - although the reaction scheme is rather simplified...

If you add NH4Cl then you are defeating the purpose of the patent.
Are you not?


170 grams of 40% w/v formaldehyde meaning 68g formaldehyde = 2.2644023mol
80 grams NH4Cl = 1.4956066mol

still 1.51:1 formaldehyde:ammoniumchloride - wierd, as the patent says that an excess of ammonium salt generally favors primary amine formation, whereas excess formaldehyde leads to dimethylamine formation..

I wonder what they meant with this! (?)

Someone should try to run this reaction twice using same conditions, only one time with no additional NH4Cl, and the other with enough NH4Cl to make for a healthy excess over formaldehyde - should reveal which ratios are really favorable!

Greetz A


placebo

  • Guest
If you edit your post then state it.
« Reply #131 on: August 11, 2004, 07:54:00 AM »
If you edit your post then state it.
Now to answer your edit, you just prove my point.
You insinuate that the NH4Cl is added to bring the ratio back to that of Vogel, and I'm asking why you would change the ratio that is stated on the patent? (The ratio which is already available in hex)
Secondly if an excess of formaldehyde was not necessary then why don't you add enough NH4Cl to make the molar ratio 1:1 ie.
170gm 40% form = 2.26 mol
80gm NH4Cl     = 1.50 mol + 0.76 mol = 40.69gm

I am just trying to understand this and I don't think your qualified to read my statements and questions let alone answer them. No offence.


placebo

  • Guest
Yes I already did the math... see above.
« Reply #132 on: August 11, 2004, 07:59:00 AM »
Yes I already did the math... see above.
Vogel... 1.3:1
Patent.. 1.5:1
Hex..... 1.5:1
Org & evervyone adds NH4Cl, why?
[edit]Is it bringing the ratio to 1:1?
I guess it does
100 hex gives 60 form and 40 NH4Cl so an extra 20 NH4Cl makes it 1:1
So I guess those Farben kids didn't spend a whole lot of time optimising the patent.


armageddon

  • Guest
reasons for ratios
« Reply #133 on: August 11, 2004, 08:10:00 AM »
OK I edited my post - your problem if you answer within five minutes... :)

there are two possibilities:

1. Excess formaldehyde normally would result in overalkylation - other story if you use alcohol to avoid it. And therefore the patent uses more formaldehyde than Vogel's, with the intention to push yields of primary amine and get back less unreacted NH4Cl.

2. They just wanted to show that even with excess formaldehyde, only monomethylamine is formed - in conrast to the standard hex/HCl method...


The example they give in the patent indeed doesn't use excess NH4Cl - but nevertheless it is stated that doing so favors monoalkylation!

I am just trying to understand this and I don't think your qualified to read my statements and questions let alone answer them. No offence

Well you are free to have your own opinion about my qualification - as long as you don't insult me by bragging about it in public (you just did so again)..

A


armageddon

  • Guest
those Farben kids were PhD's... *lol*
« Reply #134 on: August 11, 2004, 08:15:00 AM »
So I guess those Farben kids didn't spend a whole lot of time optimising the patent.

Probably. They just give an example, and leave it to the intelligent reader to make conclusions from the claims and modify their given example...

See also

Post 519651

(Lego: "How reliable is the patent literature?", Chemistry Discourse)
 ;)

How about just giving it a try? Experiment is king...
Maybe with using excess NH4Cl and trying to collect all ethylformate below 50°C to check if the patent could be optimized? That would bring this thread forth...

Greetz A


placebo

  • Guest
Re: I am just trying to understand this and I...
« Reply #135 on: August 11, 2004, 08:40:00 AM »

I am just trying to understand this and I don't think your qualified to read my statements and questions let alone answer them. No offence

Well you are free to have your own opinion about my qualification - as long as you don't insult me by bragging about it in public (you just did so again)..



Sorry, I tend to do that when people respond to me with statements that show how little they read of my post.

With the old methods the extra formaldehyde is necessary to drive the reaction. You suggest that the EtOH (and subsequent removal of ethyl formate) does this. If, with Org's added NH4Cl the ratio is 1:1, one would think some excess is necessary to start it. But some of you have already had good results.

So far I see no increase in speed (possibly longer) and dimeam is never a problem in any procedure if done correctly. Yeild will tell... coming soon.




armageddon

  • Guest
another reason
« Reply #136 on: August 11, 2004, 09:08:00 AM »
As you don't like edited posts, Placebo - here's another new one..

Another reason why Vogel's and the standard hex/HCl method use excess formaldehyde: due to high rxn temperatures, a lot of it decomposes to formic/carbocxylic before being able to act on any ammonium ions, therefore excess is needed.

Still doesn't explain the ratios used in the patent - 1.5x excess, although said oxidation shouldn't occur at all - as alcohol is used to avoid this...

Wierd.

But if the statement "oxidation of formic to carboxylic acid is suppressed by adding ethanol to rxn" (said oxidation would result in overalkylation) is correct, there would be no need to use excess formaldehyde, and the use of additional NH4Cl should present no problem but rather result in higher yields (while still not allowing for dimethylation AND keeping rxn temp low) - and in fact the yields are better when more ammonium chloride is used.


What we know so far is:

1. Additional ethanol results in lower rxn temp and no dimethylamine being formed

2. Excess ammonium chloride gives better yields than excess formaldehyde (calculated from aldehyde!) when using this patent

3. Reaction time is lengthened with alcohol


Its up to you to make guesses. IMO the alcohol makes sense when excess formaldehyde is used - but excess NH4Cl is only desirable when rxn temp is kept low, which is also accomplished by the use of EtOH - somewhat contradictory...

A


abacus

  • Guest
I agree placebo
« Reply #137 on: August 11, 2004, 12:59:00 PM »
SWIM carried out seperate experiments to explore this idea of using alcohol.

Experiment 1.  Usual method as done many times

1 mole hex
4 moles HCL in 32% solution
NO addition of NH4CL, not needed in my opinion (I agree with placebo on that)
100mls water (to stop solution being saturated)

Reaction time of 6 hours at 100DegC (water bath).
Reduced to half volume by atmospheric distillation and cooled (vogel workup, except vac not used).
NH4CL that precipitated was filtered.
Liquid again distilled until 160DegC mother liquid temp
Cooled, which formed a solid.
Solid crushed up and vac filtered, washed with ice cold ethanol, acetone and recovered methylamine.hcl dried

Filtrate again heated, cooled, and crystals collected.

Finally left with a concentrated syryp that refuses to crystalise which, correct me if i'm wrong,  Vogel states as being mostly trimethylamine
 
So, recovered colourless methylamine.hcl (with insigificant impurities IMHO) that dissolves completely in cold alcohol.  EDIT, I mean room temp methanol, and hot ethanol.

Yields range from 60-80% w/w based on starting hexamine.

Experiment 2.  Same as above, except with the additon of ethanol

1 mole hex
4 moles HCL in 32% w/w solution
NO extra NH4CL added
3 moles ethanol
100mls water

Heated to reflux for a couple hours (bath temp around 75DegC), then the formed ethyl formate was distilled out.  Once that had stopped, heated to around 100DegC for another 4 hours.

Then exact same work up as previous experiment

Yield of dried methylamine.hcl ( as opposed to the product contained in Orgys picture in this thread) was 55% w/w based on starting hex

Conclusion

Adding ethanol made temp control easier.

Less gas, slower reaction, but somewhat more pleasent.

Yield was if anything worse, following the vogel type workup as normally done, and written, by SWIM

Last point

Do you think it's possible that some bees doing IPA extractions, simply boil the IPA away and then claim that the hardened mass is their yield.  Whereas others then crush up said solid, filter, wash and dry?? which would explain some discrepancies IMO.

;)

Abacus

armageddon

  • Guest
I don't agree placebo - but anyway..
« Reply #138 on: August 11, 2004, 04:23:00 PM »
Nice! Some useful, informative post!

Now we just need someone who does the same with an excess of NH4Cl, and everything is tested out and we can all decide which procedure may be the best one... ;)

About your test of dissolving your product in MeOH or EtOH: Merck index says that ammonium chloride is soluble in both (although maybe just very slightly), so a better test would surely be using anhydrous iPrOH or even better t-BuOH or something similar...

Your syrup is supposedly diMeAm - trimethylamine cannot be formed under these conditions. They both form hydrochlorides though, so the fact it doesn't crystallize doesn't classify it as trimethylamine.

And you can in fact just boil the IPA away and claim that as your yield, if you used the IG-farben patent (with vac filtering and some acetone rinse for better drying maybe), as the procedure doesn't produce any di- or trimethylamine if done right (which you did AFAICS) - remember the hinsberg and nitrous acid test?  ;)  Therefore the IPA xtractions should only contain MeAm*HCl and HCl in traces...

[EDIT] Just realized that you wrote:4 moles HCL in 32% w/w solution - I don't know, maybe your HCl differs from mine; but usually the strength is stated as percent weight/volume (i.e. 1 liter 31.45% HCl contains 314.5 grams) - but it shouldn't make any big difference[/EDIT]

Greetz A


abacus

  • Guest
I knew you'd say that
« Reply #139 on: August 12, 2004, 10:26:00 AM »
I mistakenly omitted some information that I assumed we all knew. 

I forgot to point out that experiments involving washing the recovered methylamine.hcl with DCM and/or chloroform AND then evaporating the solvent to look for the dimethylamine residue, showed there was NO such residue, so no dimethylamine was ever formed in the reaction IMHO.

Other bees have also reported such findings, if you want, UTFSE and you'll find such agreement from others. 

As I said, I assumed we all knew this and took it for granted by now. ;)

HCL strength is stated in either w/w or w/v, depends on manufacturer, point is, make allowances to get 4 moles per mole hexamine.

Abacus