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Myrol
December 5th, 2004, 11:45 AM
Hi Folks! I've searched some time around the forum, but I was unable to find useful data about the preparation of Amines, the sort doesn't play a role :)

Ok, my background to open this Thread is mainly Ethylene Diamine......PLX type Explosives are very promising for Guys like me wich have 5Liters pure Nitromethane handy :D :D but no sensitizer! After seeing Axt 700ml PLX Blast I was so out of the House that I ordered 5Liters NM and want now an Amine!

NM could be sensitized with a lot stuff, Ammonia, Aniline, Ethylene Diamine, Methyl Amine, Propylene Diamine, Triethylamine, Propylene Triamine, Diethylamine and so on......well but what would you say how can I make mainly Ethylene Diamine without applying pressure on Dichloroethane and Ammonia-mix? I have 1Liter 72% Perchloric Acid in my stock, Ethylen Diamine dinitrate and the Diperchlorate are strong Explosives, thats also a reason to make EthDiAm! I can order it from Merck etc. but thats inpertinent expensive (65 for 1,5Liters :o ). Aniline is easy without much effort preparable, but I'm lacking Benzene to make Mari Ban Oil (Nitrobenzene) and then Aminobenzene!

Some Ideas are very recommed, because I'm planning a big Blast on Silvester with 1,5Liters PLX, Aerex, Ammex or whatever (Ammex is my Name for AMmonia-nitroMEthane-eXplosive, just a little changed from Aerex).

tom haggen
December 5th, 2004, 01:18 PM
I have a synthesis for ethyl, diethyl, and triethylamine. But it uses ethyl bromide and a concentrated ammonia and ethanol mixture under pressure. It sounded like you didn't want to use this type of reaction. But I will upload the file anyways.

vurr
December 5th, 2004, 03:05 PM
urea/carbamide is an amine.
also hexamethylenetetramine..
(if those can be used for NM)
what about ordering aniline?? should be cheaper

Marvin
December 6th, 2004, 06:32 PM
The amine needs to be a strong base. Maybe ethanolamine would work, its commonly used as a developer for home electronics boards.

FUTI
December 7th, 2004, 07:28 AM
you can use hexamethylentetraamine for amine synthesis through alkylation with some alkyl-halogenide (you get ammonium salt) and after it decomposing the adduct to obtain primary amine, formaldehyde and ammonia.
I like ethanolamine idea, it is good to try it.

Myrol
December 7th, 2004, 12:53 PM
Hmm, Ethanolamine sounds good. Do I need Chloroethanole and Ammonia to prepare it or are there some other maybe faster ways? Perhaps I'll try first some Ammex as an Explosive and later if it works good I invest some effort in REAL Amines. Thanks for replying, Has someone a book wich describes the posibillity of makinbg Ethylene Diamine via basic hydrolysis of Ethylene Urea? Its a ringmolecule with nearly finished but hidden Ethylene Diamine in the molecule! I calculated a bit and it COULD work to hydrolize it, but my first attempt was confusing.....Ethylene Diamine should smell very close to Ammonia....so I didn't know if I have made Ammonia water or the Diamine! I'll try to freeze it, if it gets solid under 8,5C it should be the Diamine.....if not its waste (Ammonia water)

Mendeleev
December 31st, 2004, 12:16 AM
Basically any primary, secondary, or tertiary alkylamine can be synthesized by reacting an alkyl halide with ammonia under anhydrous conditions, but this reaction is better for secondary and tertiary amines because you would have to use a huge ratio of ammonia to alkyl halide to get a primary amine, something like 20 to 1. Methyl amine can easily be made by by hydrolyzing hexamine. The reaction was pioneered by Organikum and goes something like 100 g hexamine dissolved in 100 mL water is added to about 325 mL 31% HCl and 130 mL ethanol, refluxed at 70-90 C for a 2-3 hours, then the ethyl formate distilled off, and the flask contents concentrated, preferably under vacuum, to give a yellow sludge wihch is extracted with IPA, and the IPA boiled off to give methylamine hcl. People have claimed to get 120 g methylamine hcl from 100 g hexamine in this reaction.

Marvin
December 31st, 2004, 01:06 PM
The alkyl halide will always produce a mixture of primary, secondary, tertiary and quaternary, and since more highly substituted amines react faster the excess of ammonia needs to be huge for a primary, and for secondary and tertiary attempts are just going to produce a mess.

General methods for pure primaries are available, like the gabriel synthesis.

"Methyl amine can easily be made by by hydrolyzing hexamine. The reaction was pioneered by Organikum "

Call me picky but this was pioneered by Eleusis on the internet in the mid 90's and widely known since then. Unless that is, I'm missing something apart from the chemists that developed the reaction in the late 19th and early 20th centurys that is.

The_Duke
January 1st, 2005, 09:31 PM
You can heat Ethylene Glycol (antifreeze) with H2SO4 (drain cleaner) and sodium chloride to produce ethylene dichloride, and then you must reflux this with strong household ammonia cleaner to get Ethylenediamine. You can also use Ethylene glycol and HCl to make Ethylene chloride, and then make a Diamine from that. :cool:

Mendeleev
January 2nd, 2005, 01:56 PM
Eleusis did pioneer the general reaction, but he was obscure about the benefits of adding alcohol to the mix, at least I found out from Organikum's posts that ethanol helps even though I had read Eleusis's procedures. I don't know anyway...

Marvin
January 2nd, 2005, 09:28 PM
The Duke,
I think making ethylene dichloride from the glycol has been discussed before without a convincing resolution. Making the chlorohydrin needs anydrous HCl and high temps or yeilds are very low, and the second alcohol group does not replace under normal conditions.

Zeitgeist
January 4th, 2005, 02:09 AM
Some 2-part epoxy adhesives have large concentrations of tertiary amines in the hardener, it has been used to sensitise NM before.

Jome skanish
January 24th, 2005, 03:11 AM
Wonder how is ethylenediamine manufactured on the industrial level.

Only route I can think of is via ethylene dichloride and ammonia. But how could ethylene dichloride be made? Acetylene + HCl?

FUTI
January 24th, 2005, 08:08 AM
But how could ethylene dichloride be made? Acetylene + HCl?

No! Addition of HCl on acetylene gives geminal dichloride. Better route would be ethene and chlorine (I guess dilution is needed?).

Jome skanish
January 27th, 2005, 05:58 PM
Geminal? Never heard of that compound, what formula does it have?

Perhaps electrophilic substiution could be prevented by choosing the right solvent. But I dont know much about solvents. Or the other chloro-compound could be separated by destillation.... but the procedure seems to be a bitch requiring a lot of advanced equipment.

Damn I cant find how industri does it either.

EDIT: Perhaps something like one of these could be used. http://ocean.otr.usm.edu/~leleuter/organic/amine1.html

Mumble
January 27th, 2005, 06:55 PM
I've heard that dibromoethane is prepared fairly simply by ethylene glycol, sulfuric, and Na/KBr. Perhaps this would be a better solution to the chloride problem. I know that the bromide seems to attach better than the chloride ion, so perhaps going the bromide route would be easier than chloride. At least I have heard this. I've seen many people say it is hard to make ethylene dichloride, but many posting success of ethylene dibromide. I know it shouldn't theoretically be this way though. Na/KBr may not be nearly as cheap as NaCl, but it is not that over bearily expensive. It is available as a pool chemical. I think it was around $7-8
a pound.

As a side note, I don't think that the Ethylene dichloride + household ammonia method will work very well for EDA. All the water will kill the reaction. I've found a reference to it's manufacture and it says that the less water the better. Liquid ammonia is best, but that is a bit hard to get and requires pressure apparatus. There was a mention of a much more feasible solution. It said that strong reflux of ethylene dibromide and a methanol solution of ammonia would yield ethylene diamine. The methanol solution wouldn't be too hard to prepare. I'll try and get the exact link tommorow when I am at school where the page is stored(I hope).

Marvin
January 28th, 2005, 01:38 AM
Jome,

Its an old school chemistry term indicating both substituants are on the same carbon, as opposed to adjacent ones (being vicinal). The abreviations more commonly seen are vic and gem.

Markovnikov rules apply to the addition of HCl to chloroethene which is the theory behind FUTI's point.