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not_important
International Hazard
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Yes, 99% will work. It's difficult to keep the lower alcohols drying than 99%.
I've seen a suggestion that the drying of amine hydrochlorides be finished in the alcohol they will be purified with. Drop the salt into the alcohol,
add some second solvent that will azeotrope with the alcohol+water, and fractionate until no more water comes over while returning the 2nd solvent to
the still pot during the drying.
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Sauron
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Dimethylamine is employed in the making of GA tabun nerve agent.
So the governments are a wee bit paranoid about it.
Rather simpleminded to embargo something so easily made.
Just like pinacolyl alcohol. From redn of pinacolone itself from the prosaic old pinacol-pinacolone rearrangement. Starting with acetone. Are they
going to ban acetone?
Sic gorgeamus a los subjectatus nunc.
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Antwain
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You know, I could be wrong, but I believe that the reagent bottle of NEt3 at uni is kept dry by the addition of an ungodly huge amount of KOH. They
just warned us not to pour that stuff at the bottom into our reactions. Would the addition of a non complexing hydrophilllic base such as NaOH or KOH
to the above amines dry them?
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not_important
International Hazard
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| Quote: | | Would the addition of a non complexing hydrophilllic base such as NaOH or KOH to the above amines dry them? |
It's not so much a "non-complexing base" as using something non-acidic, NaSO4 would done for a preliminary drying of an amine for example. KOH is a
decent drying agent, and is obviously non-acidic. The complexing issue is important in most cases.
However the methylamines are gases at SPT, so you'd be using a different arrangement to dry them, or drying them in a solvent in which case the
interaction of the solvent and strong base needs to be considered.
As for the drying mentioned earlier in the thread, much of the discussion has been on isolation the amine hydrochlorides from the ammonium chloride
byproduct. For that you don't want to use anything alkaline, nor acidic enough that it would compete with the HCl for the amine or ammonia.
While aqueous solutions of amine salts can be evaportated and dried by further heating, it often is convenient to evaportate until you have a almost
dry mush that is still reasonable easy to scape out of the container, rather than hard mass of fused amine salt. Thus the suggestion to finish drying
the salt in an alcohol solution using azeotropic removal of water. Given the large amount of NH4Cl in the product, starting with an aqueous solution,
slowly adding alcohol which will cause some NH4Cl to precipitate out, and then drying the solution by distilling away the water might be a good way to
keep amine salts from being trapped in the ammonium chloride.
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cal
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Methylamine HCL
I used a stainless steel 3" x 12" sanitary grade pipe bomb for this and other reactions. It is best to put it in the ground in a earth charcoal fire
furnace which is covered with dirt in case it does split from the pressure. This type of pipe withstands 1750 lbs psi. at 250 C.
I must tell you though that the formaldehyde and ammonia chloride method is much easier and safer to do. I made three batches in one 12 hour period
and obtained a pound of crystals. Wash them with chloroform and centrifuged  them. You can make the chloroform from bleach and acetone and the centrifuge
out of a 3/8 drill and a wood wheel.
Quote: Originally posted by Sauron  | One of the hassles in preparing methylamine hydrochloride and/or methylamine base is seperating it from the significant amount of ammonium chloride or
NH3 always present in the mix resulting from the reaction of ammonium chloride and formaldehyde.
As we have seen in the Anhydrous Ammonis from Urea thread, NH3 forms solutions with some salts, notably CaCl2, corresponding to hydrates. These are
solids (in some instances) with definite ratios of NH3 to salt such as CaCl2.4NH3 and CaCl2.8NH3 and these are designated as ammines or ammoniates.
I am wondering whether methylamine behaves similarly? |
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buzzoff
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Huh? Methylamine? Common, common chemical. Very, very restricted sales in the US. It's nice to work with the gas, if you can get it. Most can't.
If you are going to have Methylamine around the lab, it would be best if you have a very good reason for having it.
Easy to produce it from Nitromethane. Though expensive.
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Magpie
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I would think so. But Walter says the commercial aqueous solution, an HCl I imagine, is worth $15,000/gal. That sounds like BS to me. 
The single most important condition for a successful synthesis is good mixing - Nicodem
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Waffles SS
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I think writer or chemist that advise chemical matter for this serial knows nothing about chemistry.i wonder making methylamine from Hexamine(fuel
tablet)+ HCl is more difficult than making P2P from PPA and thorium nitrate? i think anyone in usa can buy fuel tablet and HCl(muriatic acid) and
there is no need to rob it from train!
[Edited on 23-8-2012 by Waffles SS]
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jon
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i made it that way making methylamine is an art
with the hexamine and paraformaldehyde.
Give me librium or give me meth!
Patrick Henry....
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jon
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here's the thing if you get qauntitative yeild it's not hygroscopic it's white you don't need to purify i got tricks up my sleeve to do exactly this,
when i was pumping out the mdxx stuff long time ago.
Give me librium or give me meth!
Patrick Henry....
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zed
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Umm. The "Breaking Bad" chemistry advice was supplied by government employees.
I think "they" have been reluctant to supply any really progressive chemical procedures. Despite all of Walter's self-professed genius, he relies on
the most mundane reactions to produce his product. The Justice Department doesn't want to provide aspiring speed chemists with useful information.
The show really isn't about chemistry; prices are skewed all out of kilter, and some of the technical information provided isn't quite kosher.
The commercial solution is generally 40% Methylamine base in water.
The show is about moral compromise and all the screwed up things that can happen at the outer edges of society.
[Edited on 26-8-2012 by zed]
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