Sciencemadness Discussion Board

Simple OrganicDiamines

Sedit - 28-6-2009 at 15:01

I was woundering if anyone had information about this chemical. I have had a very hard time finding anything at all on it and am starting to wounder if it exist in its free none salt state because all I can seem to find information on is its dihydrogen chloride salt.

The preperation of Ethylene Diamine seems that it would be a viable pathway in the reaction of Dichloroethane with ammonia.

ClCH2CH2Cl + 4 NH3 → H2NCH2CH2NH2 + 2 NH4Cl

This was going to be the compound I attempted to synthesis by chlorination of Ethylene Glycol but since I had Dichloromethane on hand I decided to try it with that.

The DCM was added to dilute aq NH3 and with shaking the DCM slowly went away leaving a cloudy mixture. I had a reference stating that the reaction with aq ammonia leads to the dihydrogen chloride product but the reaction stated above from wiki seems to suggest other wise and I can't seem to find the text that I had read this from.

I evaporated the aq mixture to yeild a small amount of tan powder that when mixed with sodium carbonate quickly liquifyed and smelled slightly of fish but since it was done on such a small scale I could not gather anything conclusive. I want to step up and see about doing this with a larger amount but the bulk of a dilute NH3 prohibits that to any real extent and I want to gather much more information before moving forward.

Is it just me or is Google slowly becoming useless for finding good information because no matter what I do I find next to nothing on Methylene Diamine, Diamino Methane, Methanediamine, ect....ect.... I have been able to find sparce information on its salt forms but nothing of its free state.


Here is a little bit of discussion that I could find on its synthesis of the sulfate salt.
http://www.sciencemadness.org/talk/viewthread.php?action=pri...

[Edited on 29-6-2009 by Sedit]

UnintentionalChaos - 28-6-2009 at 15:22

Wouldn't this compound tend to eliminate ammonia in basic environment, forming methanimine? I suspect the main product of the reaction would be hexamine, although some CH2(NH2)2*2HCl may be formed. Secondary amines (used in place of ammonia) would not be able to eliminate in this manner.

[Edited on 6-28-09 by UnintentionalChaos]

Sedit - 28-6-2009 at 16:03

Its a good possibility.
I have the same suspicions as you do about the formation of hexamine as being a product also.

Thing is why would this compound want to eliminate ammonia where as EDA does not? I have seen abstracts while one the prowl for information that stated CH2(NH2)*2HCl being used as a slow NH3 source for the formation of secondary amines so it does release NH3 but im unsure as to the conditions of it. Also would this not be a basic material to begin with?

UnintentionalChaos - 28-6-2009 at 16:17

Quote: Originally posted by Sedit  
Its a good possibility.
I have the same suspicions as you do about the formation of hexamine as being a product also.

Thing is why would this compound want to eliminate ammonia where as EDA does not? I have seen abstracts while one the prowl for information that stated CH2(NH2)*2HCl being used as a slow NH3 source for the formation of secondary amines so it does release NH3 but im unsure as to the conditions of it. Also would this not be a basic material to begin with?


It would eliminate ammonia for the same reason that methylene diol (equilibrium product of formaldehyde in water) eliminates water, but ethylene glycol does not.

Eliminating NH3 in ethylene diamine would form a three membered ring. Eliminating NH3 from methylene diamine gives a nice, happy double bond.

If the "methylene" carbon is extremely acidic, gem-diols and gem-diamines are stabilized. Look at hexafluoroacetone for a good example.

These compounds can be trapped as their salts, because electron pushing needs to occur to eject the second amine as ammonia, and the lone pair on nitrogen is bound up in a bond for ammonium salts.

[Edited on 6-29-09 by UnintentionalChaos]

sparkgap - 28-6-2009 at 16:33

Hmm...

sparky (~_~)

Sedit - 28-6-2009 at 16:42

Yes thats the link that I posted in the opening post. Still that forms the salt and im pretty sure UC maybe correct in it not being a stable compound in its free form. I suspected polymerization to hexamine but he may very well be correct in thinking that methanimine may be the product.

Sauron - 28-6-2009 at 22:35

Look in Beilstein. Look in CRC Handbook. If something that simple and small isn't known, the most likely reason is that it does not exist.

You might have tried MeBr2 or MeI2, lots more reactive than MeCl2 (DCM) If DCM did this at all it would need elevated temp and pressure.

The real methylene building block is CH2O - formaldehyde. And it loves to react with NH3 just usually in more complex ways than CH2(NH2)2 - hexamine for example. See the formaldehyde book in forum library. The title, as Bull Gates would say, is intiotive.

Also there is cyanamide H2N-CN

If that will sit still for reduction

H2N-CH2-NH2

[Edited on 29-6-2009 by Sauron]

querjek - 29-6-2009 at 05:36

Isn't there a risk for polymerization to [CH2-NH-]n?

Sauron - 29-6-2009 at 06:09

I would not be surprised.

Sedit - 29-6-2009 at 08:45

I have had a strong feeling about that also and im pretty sure thats whats taking place because after evaporating the liquid I was left with less solid then expected and after the addition of sodium carbonate the smell was much weaker then expected from a lower amine like Diaminomethane.

Some form of reaction is taking place but I have yet to determine what form and I think I am going to just continue on my original path of Ethylenediamine synthesis instead.

I was thinking of trying to brominate Ethylene glycol simular to Arrhenius iodomethane prep except using NaBr to form Dibromo Ethane and then react that with NH3 to yeild Ethylene Diamine. Sounds like it should work in theory but only time will tell.

PS: Im going to change the name of this threed to organic diamines so I can continue to discuss a working synthesis of Ethylene Diamine. If any of the mods object feel free to slap me around and change the title back. Or better yet if you can think of a more appropriate name feel free.


[Edited on 29-6-2009 by Sedit]

Sauron - 29-6-2009 at 12:18

You can find a general procedure for alkyl bromides and dibromides in Org.Sym. using NaBr and conc H2SO4 (making HBr in situ) treating alcohols and glycols.

Making ethylenediamine is a little pedestrian; I mean, it is a well known compound and AFAIK that is how it is made.

Methylenediamine is more ambitious but a bit of paper chase can take the place of a lot of cut & try. I am reminded of Tesla's famous comment on Edison, q.v.

DJF90 - 29-6-2009 at 13:15

I suspect methylenediamine not to be stable in solution. The gem-diamine has a structure similar to a carbonyl hydrate, but with -NH2 instead of -OH. I would therefore expect the gem-diamine to be in equilibrium with formaldehyde hydrate, as the water present in solution could substitute. Hexamine may also be formed (at eqm. we have both formaldehyde and NH3 in solution, and some methylamine hydrochloride may additionally be formed. If the diamine was formed in anhydrous liquid ammonia and somehow extracted and stored out of contact with alcohols or water then you might be able to isolate methylenediamine. This is just my rationalisation though.

Sauron - 29-6-2009 at 21:26

Liquid NH3 would be ideal but other aprotic solvents could be used along with NH3 (g) to achieve same end.

The question of method is premature IMO until a lit. search indicates whether this compound is known. There ought to be theoretical studies, and either preps, or failed attempted preps.

Sedit - 29-6-2009 at 22:00

I have been doing a bit of hunting with the time I'v had and still even though information of this compound seems sparce outside of its dihydrogen chloride salt I did manage to find this patant that seems to explain why there is not much talk of it.

Methylene diamine ester and method of making same -



Link: http://www.freepatentsonline.com/2290412.pdf

That states exactly what myself and everyone else seemed to suspect in that it is a very unstable creature in the freebase form but gives nothing conclusive that I could see at first glance as to what it destabilized to. Since I have seen mention of the salt being used to deliver a slow steady amount of NH3 to a reaction I'v concluded that the free form of it will more then likely lose the NH3 rather quickly but after that I don't know.

I will keep searching as much as time allows.



[Edited on 30-6-2009 by Sedit]

not_important - 29-6-2009 at 22:14

It is known

http://cameochemicals.noaa.gov/chemical/20647

and for sale

http://www.sigmaaldrich.com/catalog/ProductDetail.do?N4=6677...

http://www.mpbio.com/product_info.php?products_id=221241


not much lit on it, a possible useful related paper is
http://pubs.acs.org/doi/abs/10.1021/ja00757a042



Methylene diamine ester and method of making same
US patent 2290412



Likely routes would include reacting an alkali metal salt of phthalimide with CH2Br2, or


CH3NO2 + NaOMe => CH2(NO2)Na , + Br2 => CH2(NO2)Br , + NaNO2 => CH2(NO2)2 , then reduction of the -NO2 groups under conditions that inhibit polymerising of the diamine.


Sedit - 29-6-2009 at 22:35

Fe/HCl reduction should be able to reduce he Dinitro compond and yeild the stable Dihydrogen chloride. Since Sigma Aldrich list its storage temperature as 6 deg C then it may just be best to perform this reduction under cold conditions I would think.

I have already put in a request for that exact paper in hopes that I can find out what it destabilizes to form.

Sauron - 29-6-2009 at 22:59

Here is Ullmann's dump

Note that methylenediamine is not mentioned. Also note that oligomerization i a problem even with the ethylene compound,

8. Diamines and Polyamines

8.1. Diamines

8.1.1. 1,2-Diaminoethane (Ethylenediamine)
)

Production. 1,2-Diaminoethane is mainly produced by treating ethylene dichloride (EDC) with aqueous or liquid ammonia at about 100 °C in the liquid phase [236]. This so-called EDC process has been modified frequently [237]; the reactant ratio, product recycle, pH, reactor geometry, temperature, and pressure control the product mix. Byproducts include the higher oligomers diethylenetriamine (DETA), triethylenetetramine (TETA), and tetraethylenenpentamine (TEPA). An unavoidable coproduct of the EDC process is the amine hydrochloride, which must be neutralized with caustic soda, lime, or other bases to form, e.g., sodium or calcium chloride. Ethylenediamine is either extracted or distilled from the aqueous stream after neutralization. If deemed necessary, the higher amines can be recycled to optimize EDA production and vice versa. About two-thirds of the installed ethylenediamine capacity still relies on the EDC process.
A second process is the reaction of monoethanolamine with ammonia and hydrogen over a nickel or cobalt catalyst at 20 MPa and 150 – 230 °C [238]. The yield of 1,2-diaminoethane is 74 %, based on an ethanolamine conversion of 93 %. Byproducts are mainly DETA and piperazine, but also aminoethylpiperazine (AEP) and hydroxyethylpiperazine (HEP). The monoethanolamine process has cost advantages over the ethylene dichloride process, circumvents chloride disposal, and prevents the formation of chlorinated hydrocarbons. Lower amines can be recycled to increase the amount of higher ethanolamines; cyclic products are much more abundant than in the EDC process. Product distribution is dependent on reactant ratio, temperature, pressure, and conversion. Recently, nickel – rhenium catalysts have often been employed [239], but many other nickel catalysts with different promoters have also been suggested, for instance, Ni – Re – B supported on alumina [240] or Ni – Co – Cu – Re – B on silica [241].
A third important and very cost effective production process is the reaction of ethylene oxide with ammonia [242], as developed by Berol (now Akzo) in Sweden. Among the byproducts of this process are DETA, piperazine and di- and triethanolamine. Union Carbide has recently brought a similar process into operation. The production of diaminoethane by the reaction of formaldehyde with hydrocyanic acid, ammonia, and hydrogen [243], of chloroacetyl chloride with ammonia [244], and by hydrogenation of aminoacetonitrile [245] are of lesser importance.
Quality, Analysis, and Storage. The purity of diaminoethane, determined by titration and gas chromatography, is usually above 99 %. For storage, containers made of stainless steel and aluminum are preferred to avoid deterioration of the color number when the product is stored for long periods. Because it is corrosive, EDA should not be stored in containers made of copper, copper alloys, or uncoated iron. Frequently containers made of iron coated with plastics, such as Lupolen (BASF) or phenolic resins, are used for shipping and storing diaminoethane. Tin-lined drums can also be employed. Because the amine is hygroscopic and reacts with carbon dioxide in the air, tanks must be flushed with nitrogen before use. This also avoids discoloration during storage.
Uses. Diaminoethane is mainly used in detergents, resins, crop protection agents, paper chemicals, lubricants, and pharmaceuticals. The chelating agent ethylenediaminetetraacetic acid (EDTA) and its salts are important products, in particular in the United States. They are made by reaction of EDA with formaldehyde and hydrogen cyanide or sodium cyanide together with an excess of sodium hydroxide. Tetraacetylethylenediamine (TAED), which is obtained from EDA, is used in the detergent industry as a cold-bleach activator. It has become the fasted-growing EDA product in the last years. Hydroxyethylethylenediamine is also converted into chelating agents. Several nitrogen-containing surfactants are produced from fatty acids and EDA or aminoethylethanolamine, available from EDA and ethylene oxide. Nonreactive polyamide resins produced from EDA and diacids also consume large amounts of EDA. They find use as adhesives and for printing inks.
The zinc and manganese salts of ethylene-bisdithiocarbamic acid, obtained from EDA, are used as fungicides (maneb, mancozeb, zineb or metiram) and have a significant market. Other fungicides based on EDA are known, e.g., those of the imidazoline type.
The EDA-derivative N,N-ethylene bis(stearamide) (EBS) has lubricating properties and is used as a mold-release agent, for the processing of thermoplastic resins, in paper coating, wire production, etc. EDA is also used for gasoline and lubricant additives and for surfactant production.
Diaminoethane – polyester condensates that are hydroxymethylated with formaldehyde can be used as plasticizers for phenol – formaldehyde resins [246]. The use of condensates of diaminoethane, epoxides, and urea as nitrogen-containing polyol components for the production of polyurethane foams is proposed in [247]. The addition of EDA to viscose fiber spinning baths is said to improve the tensile strength of the fiber [248]. In the wet spinning of polyurethane fibers, diaminoethane is a rapid-action curing agent [249]. The incorporation of diaminoethane into diisocyanate – polyester prepolymers results in useful polymers for the production of elastic polyurethane fibers [250]. Ethyleneurea derivatives prepared from diaminoethane are used for textile finishing. Diaminoethane is employed as a stabilizer for rubber latex. In the mineral oil industry, diaminoethane can act as a stabilizer for halogen-containing high-pressure lubricating oils [251] and, in the form of Schiff bases with ketones, is also used as a metal deactivator [252].
Economic Aspects. Ethylenediamine and its homologues are large-scale chemical products. The global demand for ethyleneamines in 1998 was estimated at 250 000 t [253]; capacities are around 340 000 t/a. The European market is ca. 100 000 t/a with an annual growth rate of 3 – 4 % [254]; the U.S. market has a similar size, and the Japanese is ca. 15 000 t/a. Major producers are Union Carbide, Dow, Akzo Nobel, Tosoh, BASF, and Bayer. In the United States and Japan, the ethylenediamine market is smaller than that of the higher ethyleneamines, and vice versa in Europe.


[Edited on 30-6-2009 by Sauron]

DJF90 - 30-6-2009 at 04:53

Heres the article not_important cited:


Attachment: Methylene derivatives....pdf (711kB)
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Sauron - 30-6-2009 at 05:09

Hate to tell you but I posted that paper in Refs for sedit yesterday. And as far as I can see it is a useless potentiometric study of distantly related systems and of no preparative significance at all. I only gace it to him because he asked for it.

Nicodem - 30-6-2009 at 06:02

gem-Diamines are stable compounds in the form of their salts or amides. The methylenediamine sulfate can be prepared from HCHO, NH3 and H2SO4 (see the attached paper: JACS, 70, 3659-3664). Its diformamide (HCONH)2CH2 can be prepared from HCONH2, HCHO and H2SO4 (see Chemische Berichte, 97, 297 - 298), and this can be hydrolysed to methylenediamine sulfate.

Attachment: The Reaction between Formaldehyde and Ammonia.pdf (769kB)
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[Edited on 30/6/2009 by Nicodem]

Sauron - 30-6-2009 at 09:22

Wow. A whopping 13% tield amounting to < 500 mg.

Still I suppose it's like a dog walking on its hind legs. It isn't that the dog does it well but that the dog can do it at all.

Formatik - 30-6-2009 at 14:21

Methanediamine Beilstein reference is 1 [I] 306, [II] 648. I don't have those. Though Beilstein 1 61 does mention heating CH2Cl2 with alcoholic NH3 to 100-125° forms (CH2)6N4; heating CH2Cl2 with aqueous NH3 to 200° forms HCl, HCOOH, and CH3NH2.

Sedit - 30-6-2009 at 15:08

So it does form Methylamine then Formatik?
I thought alot about it being a novel MeNH2 synthesis after UnintentionalChaos mentioned the possible formation of Methyleneimine but could not figure an efficiant way other then neutralizing with HCl and fractional crystalizing to seperate the Ammonia Chloride and Methylamine. Since I did not want to waste HCl not knowing if it formed or not I did not attempt it.

Its good to know thank you Formatik. Do you have a link to the given reference?

Sauron - 30-6-2009 at 17:17

DCM amd aq NH3 @ 200 C will be a pressure reaction, and looks to me like HCl, MeNH2 and HCOOH can only form N-methylformamide hydrochloride under those condirions.

CH2Cl2 + NH4OH -> HCONHCH3.HCl + HCl

which does not tell the whole story since excess base will make NH4Cl and free the formamide base while excess acid would drive the reverse reaction to formic acid and MeNH2.HCl

not_important - 30-6-2009 at 19:18

Quote: Originally posted by Sauron  
Wow. A whopping 13% tield amounting to < 500 mg.


But cheap materials, not too difficult to preform, and the K2CO3 should be mostly recoverable.

Formatik - 30-6-2009 at 20:02

Quote: Originally posted by Sedit  
So it does form Methylamine then Formatik?
I thought alot about it being a novel MeNH2 synthesis after UnintentionalChaos mentioned the possible formation of Methyleneimine but could not figure an efficiant way other then neutralizing with HCl and fractional crystalizing to seperate the Ammonia Chloride and Methylamine. Since I did not want to waste HCl not knowing if it formed or not I did not attempt it.

Its good to know thank you Formatik. Do you have a link to the given reference?


Beilstein's Handbuch can be found in big uni libraries. Volume 1 of the last printed edition (4. Auflage) is on google books or archive.org, or in a link in my profile. I don't have the supplements. There might also be the option of accessing Beilstein Crossfire at an uni. The references for those reactions are given by Beilstein. I still haven't considered if the older editions might not have some info.

Sauron - 30-6-2009 at 21:55

Almost the complete Hauptwerk (4th Auflage) that is, Bands 1-16 which is everything but the ten or so volumes on heterocyclic systems, were digitized by titan and posted on the Russian forum, with links given ub References - I know because I downloaded them. I have them on a CDR. Maybe a DVD I don't recall.

This is the Beilstein Main Work covering the lit. through 1910.

The five supplement sets are organized in same fashion and extend coverage till IIRC c 1970 but alas no one has seen fit to scan them - a daunting undertaking that would be!

Sedit - 1-7-2009 at 10:47

Ok I just want to make sure I have all my ducks in a row hear before I attempt this again hopefully later tonight. Even though I am not getting what I was expecting I have gained an interest in this reaction due to the fact of it being a 'novel' Methylamine and Formic acid synthesis.

When the DCM reacts with (aq)NH3 the products are HCl, Formic acid, and Methylamine. The Methylamine will most surely react with the HCl and go into solution as the hydrogen chloride salt but I can't help but wounder about what Sauron said about the formation of formamide or ammonia formate at the very lest. It seems like there are many factors at work here and since I know next to nothing about figureing up the way the equilibrium should work I will have to assume that the majority of product will be MeNH2*HCl and Formic acid.

I am in a toss up of if I should generate the (aq)NH3 directly prior to reacting it with the DCM or generate it when DCM+H2O are already together. More then likely will not make much difference but my main concern is how to reflux this without loss of NH3. What is the azeotrop of NH3+H2O so that the NH3 stays in solution even though its being refluxed if at all possible. I am also annoyed by the fact that excess NH3OH will raise the PH and free any MeNH2 from its salt and generate additional chloride.

Work up:
I would think the best way would be to heat until the PH drops to a steady place near neutral from the consumption of NH3 into the salts.

Distill the fluids and titrate distillate to try and figure out the formic acid concentration.

Weight remaining salts and test melting point ect..ect..

If all seems well I would think that freeing the formed MeNH2 and feeding it into water(MeOH?) and titrate should give me a round about value of the MeNH2 made also in the reaction.



Any thoughts, or other ways I could go about trying this and determining what is formed?

[Edited on 1-7-2009 by Sedit]

Nicodem - 2-7-2009 at 00:05

Quote: Originally posted by Sedit  

I am in a toss up of if I should generate the (aq)NH3 directly prior to reacting it with the DCM or generate it when DCM+H2O are already together. More then likely will not make much difference but my main concern is how to reflux this without loss of NH3. What is the azeotrop of NH3+H2O so that the NH3 stays in solution even though its being refluxed if at all possible. I am also annoyed by the fact that excess NH3OH will raise the PH and free any MeNH2 from its salt and generate additional chloride.

What are you talking about? What methylamine? What reflux? To get a redox reaction going you need to heat the mixture way beyond the CH2Cl2 boiling point! Do you use an autoclave or not?

Sedit - 2-7-2009 at 08:54

The Methylamine was one of the products of the high temperature reaction but you have made your point about the autoclave I ignorently overlooked it because of the appeared reaction at lower temperature. Since I do not have an autoclave and be damned if im going to stopper up anything and just heat that can not be tested.

However there appears that some reaction takes place even at room temperatures with stirring so im left to wounder what the products formed are. Some equilibrium that can not make it all the way to the right without the high temperatures or what?

Here is what I have observed so far by just mixing and shaking and evaporating. It did not go as planed hence the reason I started this threed because the information on what I thought would form is just not there.

When the Dichloromethane and (aq) ammonia are mixed together the DCM appears to be consumed and the solution goes cloudy. Initial thoughts where that there where sufficants in the Ammonia because I would expect a formed salt solution to be clear. I evaporated some of the original Ammonia solution but it evaporated cleanly with no residue like I would expect with sufficants. Then there was the issue of DCM's solubility in H2O so the same bulk of non ammonia H2O was added to some DCM and shaken just the same yet it quickly droped to the bottom leaving a clear solution completely different then when shaken with (aq)Ammonia.

The cloudy solution was then evaporated on a low heat at first to see if DCM left the solution boiled out but there was no sign of it and the solution retained its cloudy consistency all the way to the end of its evaporation leaving behind a small amount of light tan powder that did not appear to be enough for the amount of DCM used to begin with. Excess NH3 could be smelled when the solution was first heated making me wounder how any salt could be formed due to the high PH enviroment yet there was something left behind that acted like an amine by liquifying when added to sodium carbonate/NaOH (trace NaOH because the sodium carbonate came from waste NaOH that was left out to react to the elements. Used for throw away experiments to not waste the cleaner reagents I have) and the slight smell of fish could be detected simular to the alkylamine smell of epoxy hardener.

I understand that this is not all scientific but thats why I wanted to repeat this again under better controled conditions.

Improvments to rule out as much contamination and variables as possible will include refluxing the DCM in activated carbon and redistilled to make sure that there is no contamination in the DCM getting in the way. It appears to have cleared it up a bit but since it was clean looking to begin with its hard to tell.
Also I want to generate a higher concentration of (aq)NH3 to rule out DCM just going into solution normaly and im looking for the solubility of DCM in a high PH enviroment.
Higher heat to push any equilibrium that may setup further to the right. Since I do not have an autoclave I plan on packing the condenser with glass wool within reason to build slight pressure and reach a little higher temperature.

I hope all this clears up what my intentions and reasoning behind them is. Keep my sig in mind because if I knew what the hell I was doing I wouldn't have half as much fun doing it:D

~Sedit