madscientist
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Carboxyl amines
I have been intrigued for a while with the idea of carboxylic amines. They would be produced by the reaction of a peroxycarboxylic acid with ammonia
solution; this forms the peroxycarboxylic acid ammonium salt. That immediately decomposes into a carboxylic amine. The carboxylic amine seems to be
less stable than the peroxycarboxylic acid that the carboxylic amine was derived from. Wow... there is a lot I have to say on this topic that I have
discovered (I have had to figure everything out on my own; I have been unable to even find a mention on carboxylic amines anywhere, not even in my
1500 page organic chemistry college text or many thousand paged chemical dictionary). One important tid-bit of information is the reaction of 27.5%
hydrogen peroxide solution with 10% ammonium hydroxide solution: it is very gradual; very tiny bubbles form slowly and stream up to the surface. I am
not sure if the bubbles are composed of nitrogen gas or oxygen, for hydrogen peroxide decomposes readily in an alkaline solution.
Dicarboxylamine (COONH2)2
This would theoretically be produced by the reaction of peroxalic acid with ammonia solution. However, peroxalic acid is exceedingly unstable; an
aqueous solution of peroxalic acid will fizzle and foam when stirred. Because of this, I knew the only chance of success was to have the peroxalic
acid formed and immediately reacted with the ammonia. I will list every experiment on it that I can remember doing. I concluded that dicarboxylamine
is too unstable to be worth considering using; it seems to be even more unstable than peroxalic acid.
1) I placed 10g (COOH)2 in a beaker. I then added 27.5ml 27.5% H2O2 solution. I then added 30ml of 10% ammonium hydroxide solution (that would
translate into approximately 4.86% ammonia solution). I then added 2ml of concentrated H2SO4. Immediately the beaker began foaming furiously, as the
oxalic acid was converted into peroxalic acid, then ammonium peroxalate, then dicarboxylamine, then carbon monoxide water and nitrogen gas. It was
decomposing upon formation.
This provided other important information: the formation of a peroxycarboxylic acid requires the presence of the sulfate ion; it does not require the
presence of sulfuric acid. However, I would continue to typically use sulfuric acid, for because of its chemical properties, it works more effectively
as a catalyst. If I decided not to use sulfuric acid, I used magnesium sulfate.
2) I did the same experiment as experiment #1, except that I substituted the 2ml of concentrated sulfuric acid with a gram of magnesium sulfate. My
sulfuric acid is high in selenium content, and so it is brownish yellow, making it difficult to observe color changes. This time however all of the
reactants were colorless. The solution, while foaming, became a urine-yellow color (I'm assuming that is the color of dicarboxylamine); but by the
time the foaming had subsided, it had become relatively colorless again. This reaction was slightly slower than when sulfuric acid was used, due to
the ionization of hydrogen sulfate as opposed to magnesium sulfate.
Acetic amine CH3COONH2
This time I produced the peroxycarboxylic acid first, then reacted it with the ammonia solution.
1) I poured 10ml of 27.5% H2O2 solution into a beaker. I then added 55ml of 5% CH3COOH solution. To this I added 2ml of concentrated H2SO4. I let this
reaction continue for about three hours (industry allows the reaction to continue for ten days for the purpose of achieving maximum yields). I then
slowly poured 57ml of 4.86% ammonia solution into the beaker. The temperature rose quickly from about 18 degrees Celcius to about 45 degrees Celcius.
This is evidence that acetic amine was formed (no bubbles but evolution of heat means that the following equation occured: CH3COOONH4 --} CH3COONH2 +
H2O). (note: for some reason this board isn't allowing me to use the symbol usually used to create an arrow...) The rate of bubble formation was about
eight times higher than when 27.5% H2O2 solution and 4.86% ammonia solution is mixed. When stirred violently with a stirring rod, the solution began
to fizzle, and foam if I stirred for long enough.
From this I can deduce that acetic amine is also too unstable for use.
Citric amine C6H11O7N3
This seems to have a chance of being stable enough for use.
1) I placed 5g of citric acid in a beaker. To this I added 10ml of 27.5% H2O2 solution. I then added 1ml of concentrated sulfuric acid. I let this
react for four hours (once again, to achieve maximum yields the reaction must be allowed to continue for several days). I added 10ml of 4.86% ammonia
solution, and the temperature literally JUMPED (as in during a time frame of under two seconds) 30 degrees Celcius (from 20 degrees Celcius), and
visible wisps of ammonia gas began to form. I immediately placed the beaker in an ice bath. I continued to *slowly* add another 47ml of 4.86% ammonia
solution (I added slightly more than originally planned to account for the ammonia lost earlier). Bubbles formed extremely slowly, even more slowly
than when 27.5% H2O2 solution is mixed with 4.86% ammonia solution. The rate of bubble formation changed little when stirred violently.
Now for information on harvesting a carboxyl amine.
I will write the instructions for citric amine. First one would procede to evaporate off all traces of water. One would then be left with a mixture of
citric amine, ammonium sulfate, and ammonium citrate crystals. To extract the citric amine, one would place the crystals in a beaker of acetone,
adding acetone until the crystals are no longer dissolving further; then pouring the mixture through a filter. The filtered liquid should be
evaporated off. What is deposited by the evaporating acetone is citric amine.
I weep at the sight of flaming acetic anhydride.
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Polverone
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Given that you cannot find literature references for these compounds, how do you know what is happening/what you are making? For example, when you add
sulfuric acid to a mixture containing aqueous ammonia, hydrogen peroxide, and an organic acid, and you observe a reaction, how do you KNOW that carbon
monoxide and nitrogen are coming off? I don't really see why amines should be forming at all. If you make some percarboxylic acid, I would expect the
addition of ammonia to form an ammonium salt of the acid, not an amine. Like in your second reaction, you're trying to form peracetic acid and then
react that with ammonia, right? Why shouldn't there be a straightforward acid-base reaction that results in ammonium peracetate (or if that is
unstable, ammonium acetate)? But perhaps this is my ignorance of organic chemistry showing and you will shortly enlighten me. For that matter, I would
expect the sulfuric acid you're using to catalyze things to suck up any ammonia (being a stronger acid than your intermediate compound) unless you
somehow purified your percarboxylic acid or used a considerable excess, in which case you still have massive purity problems.
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madscientist
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The formation of the amines would actually be the result of an acid base reaction. The ammonium peroxycarboxyl salt would be formed; it oxidizes
itself immediately forming the carboxyl amine and water. I don't have time right now to offer evidence and an explanation for how I know that's what
happens. I believe the carboxyl amines are too unstable; i believe that tertinary organic nitrides are being formed (that's why all of the solutions
of carboxyl amines bubble for a little while).
I weep at the sight of flaming acetic anhydride.
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PHILOU Zrealone
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2NH3 + 3H2O2 --> N2(g) + 6H2O
An increase of T is normal in your case and is absolutely no proof of carboxamide formation since H2SO4 conc is present in your mix adding NH4OH will
result in acid base neutralisation what heats a lot!
NH4-O-O-CO-CO-O-O-NH4 --> NH2-O-CO-CO-O-NH2 + 2 H2O
NH2-O-CO-CO-O-NH2 --> N2(g) + 2H2O + 2CO(g)
CH3-CO-O-O-NH4 --> CH3-CO-O-NH2 + H2O
CH3-CO-O-NH2 -->( CH3-CNO + H2O) --> CH3-CO2H + 1/2 N2(g)
A good idea would be to do this experiment with a good cooling (much below 30°C), with no H2SO4- use MgSO4 instead!
Stoechiometry is important here!
*10g H2C2O4 is 0,111 mole and thus contain 0,222 mole of H(+) since it is a diacid!
*27,5ml of H2O2 27,5% means approx 7,57 g pure H2O2 or 0,223 mole (you indeed need twice the amount to peroxydise two acid sites/molecule).
*30ml NH3 10% means approx 3g pure NH3 or (0,176 mole) and you need 0,222 (so some 6,16 ml more NH3 solution!).
Also a good idea would be to first see if MgSO4 is stable with H2O2 since many metalic cation decompose H2O2!
Also as a final remark, better use all ingredients cold and as concentrated as possible (to keep as much water solvant out) if you ever want to
isolate (if it is possible) a solid intermediate of carboxamide.
So better use NH3 dry gas (made by solid NH4NO3 + solid NaOH) bubbled into the peracid solution made by the action of 50%H2O2 on the 100% acid (with
an excess of peroxyde).As a catalyst you could also use dry Mg persulfate (or Na persulfate).
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madscientist
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So, a peroxycarboxylic acid can be prepared by reacting a carboxylic acid with hydrogen peroxide in the presence of sodium persulfate or magnesium
persulfate? If so, could ammonium persulfate be used instead? I can get ammonium persulfate easily, but I would have to prepare my own sodium
persulfate or magnesium persulfate.
Something that I remember occuring in the past: I remember that after allowing a solution of mostly (COOOH)2 (it hadn't been peroxidized for long
enough) to react with an excess of NH3 solution. There was a pale yellow solid that remained after evaporation. I believe the yellowish color could be
accounted for because of the brownish color of my sulfuric acid. I plan to soon prepare some clear sulfuric acid, so I will be able to observe color
changes and eliminate impurities for delicate reactions. The solid didn't seem to have the properties of (COONH4)2. I propose that it is NH4OOC-(C=O)-
(C=O)-COONH4. This is my postulated series of reactions for how this compound could be formed:
(COOH)2 + H2O2 --(H2SO4)--> HOOC-COOOH + H2O
HOOC-COOOH + 2NH3 --> NH4OOC-COOONH4
NH4OOC-COOONH4 --> NH4OOC-COONH2 + H2O
NH4OOC-COONH2 --> [NH4OOC-CO] + H2O + 1/2(N2)
2[NH4OOC-CO] --> NH4OOC-(C=O)-(C=O)-COONH4
I weep at the sight of flaming acetic anhydride.
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PHILOU Zrealone
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Of course you could use NH4 persulfate!
But the only thing I don't know for sure, is that does NH4(+) stands the H2O2, I guess well!
Normally to get carboperoxyacids one would use 100% H2O2 and 100% H2SO4 to get a 87% solution of H2SO5 in water!This is then added cold to the 100%
carboacid!This acid is also used to transform some amines in nitrocompounds via peroxydation of the amine!
With 33% H2O2 and 100% H2SO4, you can only reach 66,5% H2SO5 in water!
If you have NH4 persulfate, use it!
It would be again more wise to insert dry NH3 gas under cooling in the peracid (to avoid introducing more water)!
H2SO4 can trun brown indeed and make your product colored!
What do you mean by: the compound din't seem to display the properties of ammonium oxalate?
It has or it hasn't the properties!What tests did you perform?
NH4OOC-(C=O)-(C=O)-COONH4 is one of your postulated compound
Following:
HO2C-CO2H + H2O2 -(H2SO4)-> HO2C-CO3H + H2O
HO2C-CO3H + 2NH3 --> NH4O2C-CO3NH4
NH4O2C-CO3NH4 --> NH4O2C-CO2NH2 + H2O
NH4O2C-CO2NH2 --> [NH4O2C-CO] + H2O + 1/2 N2
2[NH4OOC-CO] --> NH4OOC-(C=O)-(C=O)-COONH4
But unfortunately, a sequence of 3 CO next to each other doesn't exist long!
-CO-CO- exists in glyoxal or in oxalic acid.
-CO-CO-CO- is very unstable especially if
HO-CO-CO-CO-OH --> HO-CO-CO-H + CO2
HO-CO-CO-H --> CO2 + CH2=O + HO-CO-CH2OH + HO2C-CO2H
So a sequence of 4 is rather unthinkable (unlikely).It would eather loose CO2 or CO to go lower in -CO-!
Also one of the first reaction is:
HO2C-CO3H --> HO2C-OH + CO2 --> H2O + 2CO2
because CO-CO bond is strong reducer and O-O bond is strong oxydiser!
HO-CO-CO-O-OH will not survive long (especially in hot/basic or sunlight conditions) You need cold place, pure concentrated chemicals, dry NH3, strong
cooling!
If you suspect radical process like
NH4O2C-CO2-NH2 --> NH4O2C-CO° + H2O + 1/2N2
and then
2NH4O2C-CO° --> NH4O2C-CO-CO-CO2NH4
NH4O2C-CO-CO-CO2NH4 --> NH4O2C-CO2NH4 + 2 CO
It can aswel be directly:
NH4O2C-CO2-NH2 --> NH4O2C° + H2O + 1/2N2 + CO
2 NH4O2C° --> NH4O2C-CO2NH4
What leads to the same compounds independantly from the way we look to the problem!
PH Z
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PHILOU Zrealone
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Ah yes!
Also about percarbo acids:
R-CO-O-CO-R + H2O2 --> R-CO2H + R-CO3H
Starting from 100% H2O2, you end with 50% peracid solution that is hard to separate from its unperoxydised brother (vaccuum distillation)-but big
risks of explosions especially with low molecular weight acid like acetic or formic!
Formic acid has a perfect OB and is an isomer of carbonic acid H2CO3 (HO-CO-OH)!
HCO3H (H-CO-O-OH)--> H2O + CO2 + heat
PH Z
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