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Topic: Why does amines react with nitrous acid differently than other acids?  (Read 2148 times)

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Offline magdi_gamal

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I mean why is it that the common formula for amines reacting with acids is...
RNH2 + HX  :rarrow:  RNH3+X-

But when amines react with nitrous acid it goes like this even though that nitrous acid is also a bronsted acid?
C2H5NH2 + HNO2  :rarrow:  C2H5OH + H2O + N2

Offline Archer

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Re: Why does amines react with nitrous acid differently than other acids?
« Reply #1 on: March 29, 2014, 03:17:21 PM »
How stable is HNO2?

Draw out the full structure of HNO2 how might an amine primarily react with this? What about if HNO2 degrades, what are the degradation products? How might these react with a 1° aliphatic amine?
« Last Edit: March 29, 2014, 03:29:45 PM by Archer »
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Offline AlphaScent

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Re: Why does amines react with nitrous acid differently than other acids?
« Reply #2 on: March 29, 2014, 10:12:55 PM »
I thought primary amines and nitrous acid give azides?
If you're not part of the solution, then you're part of the precipitate

Offline AlphaScent

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Re: Why does amines react with nitrous acid differently than other acids?
« Reply #3 on: March 29, 2014, 10:16:26 PM »
whoops..I meant diazide..big difference
If you're not part of the solution, then you're part of the precipitate

Offline Archer

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Re: Why does amines react with nitrous acid differently than other acids?
« Reply #4 on: March 29, 2014, 11:56:16 PM »
I thought primary amines and nitrous acid give azides?

They give diazonium salts and they are relatively stable if they are aromatic amines.

If they are aliphatic 1° amines, however,  they tend to lose N2 leaving a carbocation to pick up some water, eliminate a proton or pick up a halide.

CCC[N+]#N   :rarrow:  N2 + CC[cH2+]
“ I love him. He's hops. He's barley. He's protein. He's a meal. ”

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Offline Archer

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Re: Why does amines react with nitrous acid differently than other acids?
« Reply #5 on: March 30, 2014, 12:08:56 AM »
Aromatic diazomium compounds are more reliable so one can get a wider range of FGI's than aliphatics. I guess this is why this reaction for converting R-NH2 into R-OH
“ I love him. He's hops. He's barley. He's protein. He's a meal. ”

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