Topic: methylamine synthesized ala Bright Star´s:it´s good enough? (Read 1851 times)
The temp climbed up to 108°C over 5.5h. After about 300 minutes a white smoke started filling the distilling flask. This is what we are waiting for, the sublimation of the MeAm.HCl. "Distilling to dryness," means the flask doesn’t have any more water in it. It does not mean, "Boil the hell out of it till everything's crunchy"
Once the smoke appeared, the heat was turned off and the contents were left to cool and solidify for 30 minutes. Sorry, the appearance of the fluid at this point wasn't noted. Once cool, 350mL MeOH was poured into the distillation flask and a reflux condenser was put on the flask (actually, the condenser from the distillation phase can be used, as it is already set up and this isn't a heavy reflux). The heat was turned up again, and the solution was allowed to reflux for about 15 min.
While hot, the solution was decanted into a Pyrex dish (a 1000mL beaker is probably better). Either way, the container was covered with saran wrap and left on the counter for 2 hours until cool. It was then moved to the fridge and left overnight. In the morning the beaker was moved to the freezer for another 2 hours. The crystals were large crunchy flakes, and the remaining fluid had an amberish tint.
the way to keep temps in that range is by reacting it in a boiling saturated solution of table salt it boils exactly 106 i bunged 32 ounce beer bottles to an aspirator and pulled a very gentle vacum if the vacum is to high you will know because it will simply foam out.
that way folks can try to answer (and is prbly why no one has 
)
)Hydrolysis of Hexamine to paraforamide
140g of Hexamine is carefully dissolved in 400mL of Muriatic Acid (31.45% HCl) to which at least 100mL of (preferably) absolute ethanol has been added. Add the hexamine slowly while stirring vigorously and with good ventilation as some nasty fumes are produced. Allow all to stir at room temperature for at least 8 hours but preferably 16. The solution will become turbid within several hours of the initial mixing. I *believe* this is the formation of a formaldehyde trimer of some sort and I suspect that the original equation for the conversion of hexamine into methylamine fragments is therefore incorrect. At any rate, filter off this white precipitate which is obviously not an amine salt due to it being fluffy even in Florida's humidity (almost all simple amine salts are hygroscopic). Finally, remove the excess water, hydrochloric acid and freako volatile products by, ideally, heating the liquid at low to medium heat in a porcelain saucepan. Stove-proof glass would be ideal, but stainless-steel, aluminum and copper are definitely not! The concentration can generally be left unattended for a couple of hours, but try to stick around and babysit it at least the first time so you will have a good idea of how long it takes for your particular stove/pots/etc... Also, the methylamine HCl will form a melt if heated too long at which point it will sublimate off. It will then appear as if it's taking forever for the stuff to concentrate when in fact you are merely boiling your product away. After the concentrated slush has become sufficiently "thick", take it off the heat every so often to see if it doesn't soldify, insuring that the water is mostly gone and that not too much sublimation has occured (some is inevitable and even desireable). The yield of Methylamine HCl should be around 200g as white deliquescent crystals.
d) Notes on the process
If the crystals are opaque white and do not deliquesce quickly in air of average humidity (65% rh), they may be contaminated with some Hexamine or some bizarre polymer. Washing 100g of the crude product with 100mL of Chloroform by stirring in a beaker then filtering, repeated as many times as necessary, will remove Hexamine. Methylamine HCl is insoluble in Chloroform whereas Hexamine is at the rate of 1g to 10mL.
It has been determined that the best batch size is to process 70g of hexamine at a time. This is primarily due to the fact that the amount of heat necessary to boil something increases exponentially with the volume. It seems to normally take 4-6 hours to fully concentrate the methylamine solution with a 70g batch but as much as 16 hours to do 200g. Of course, the solution can be split up among pans to evaporate, but try and keep it at 100g expected yield per pan to get the best tradeoff between time and volumetric efficiency
Hexamine, hcl and reflux does in fact work fine...
Otherwise caffeine in a concentrated lye solution and distill off methylamine. 100gr caffeine has about ~15g methylamine yield.
If you do the reaction in anhydrous ethylene glycol (antifreeze) you can distil off dry methylamine gas.
co2 evolution is visible from the top of the reaction soup ie. no co2 should be seen bubbling from the bottom.
any further questions feel free to ask
