One-step ammonium picrate?

[roux]

I was thinking...if it's possible to nitrate phenol without sulfuric acid and only nitric acid, could the nitric acid be replaced with ammonium nitrate? If it could be done it would leave TNP and an excess of ammonium hydroxide. The ammonium hydroxide would react with the TNP and make ammonium trinitrophenoxide.

[roux]

I was thinking...if it's possible to nitrate phenol without sulfuric acid and only nitric acid, could the nitric acid be replaced with ammonium nitrate? If it could be done it would leave TNP and an excess of ammonium hydroxide. The ammonium hydroxide would react with the TNP and make ammonium trinitrophenoxide.

[roux]

I was thinking...if it's possible to nitrate phenol without sulfuric acid and only nitric acid, could the nitric acid be replaced with ammonium nitrate? If it could be done it would leave TNP and an excess of ammonium hydroxide. The ammonium hydroxide would react with the TNP and make ammonium trinitrophenoxide.

[The_Duke]

Good idea, and worthy of a discussion too, but let me get this straight. You don’t want to use H2SO4 and you don’t want to use HNO3, so you are going to simply add NH4NO3 to Phenol and hopefully the reaction will produce TNP and then from there the reaction will progress to form Ammonium Picrate, is this right?

I don’t think it will work exactly like that, I would try using HCl, NH4NO3 and Phenol in one pot, it just might work (But it might not). I’m not sure if there will be any major side reactions while using HCl.

One step Ammonium Picrate, I like the sound of that. :)

[The_Duke]

Good idea, and worthy of a discussion too, but let me get this straight. You don’t want to use H2SO4 and you don’t want to use HNO3, so you are going to simply add NH4NO3 to Phenol and hopefully the reaction will produce TNP and then from there the reaction will progress to form Ammonium Picrate, is this right?

I don’t think it will work exactly like that, I would try using HCl, NH4NO3 and Phenol in one pot, it just might work (But it might not). I’m not sure if there will be any major side reactions while using HCl.

One step Ammonium Picrate, I like the sound of that. :)

[The_Duke]

Good idea, and worthy of a discussion too, but let me get this straight. You don’t want to use H2SO4 and you don’t want to use HNO3, so you are going to simply add NH4NO3 to Phenol and hopefully the reaction will produce TNP and then from there the reaction will progress to form Ammonium Picrate, is this right?

I don’t think it will work exactly like that, I would try using HCl, NH4NO3 and Phenol in one pot, it just might work (But it might not). I’m not sure if there will be any major side reactions while using HCl.

One step Ammonium Picrate, I like the sound of that. :)

[Boomer]

"it would leave TNP and an excess of ammonium hydroxide"

With hydroxide in excess, the nitric would combine with it, instead of forming TNP. Or better phrased, why should the AN split into ammonia + nitric, to have the ammonia combine with the weaker picric acid? (I know it is not that weak, just hardly soluable.)

If you add sulfuric or HCl, the AN does split, but with these acids present, no picrate will form.

This one-step synth will stay a dream I fear. You can make it a one-pot synth though. Make TNP the usual way, or by weak nitric alone, then add excess ammonia. Separate by crystallisation, or use the dried picrate/AN mix as-is (if no sulfuric was used).

[Boomer]

"it would leave TNP and an excess of ammonium hydroxide"

With hydroxide in excess, the nitric would combine with it, instead of forming TNP. Or better phrased, why should the AN split into ammonia + nitric, to have the ammonia combine with the weaker picric acid? (I know it is not that weak, just hardly soluable.)

If you add sulfuric or HCl, the AN does split, but with these acids present, no picrate will form.

This one-step synth will stay a dream I fear. You can make it a one-pot synth though. Make TNP the usual way, or by weak nitric alone, then add excess ammonia. Separate by crystallisation, or use the dried picrate/AN mix as-is (if no sulfuric was used).

[Boomer]

"it would leave TNP and an excess of ammonium hydroxide"

With hydroxide in excess, the nitric would combine with it, instead of forming TNP. Or better phrased, why should the AN split into ammonia + nitric, to have the ammonia combine with the weaker picric acid? (I know it is not that weak, just hardly soluable.)

If you add sulfuric or HCl, the AN does split, but with these acids present, no picrate will form.

This one-step synth will stay a dream I fear. You can make it a one-pot synth though. Make TNP the usual way, or by weak nitric alone, then add excess ammonia. Separate by crystallisation, or use the dried picrate/AN mix as-is (if no sulfuric was used).

[simply RED]

Tricks are for kids ...

[simply RED]

Tricks are for kids ...

[simply RED]

Tricks are for kids ...

[roux]

I really don't see how if TNP can be formed by a hydrogen cation and a nitrate anion, yet not from an ammonium cation and a nitrate anion.

Also, I don't think it's possible for a nitro group bonded covalently to a benzene ring could revert back to a nitrate ion.

[roux]

I really don't see how if TNP can be formed by a hydrogen cation and a nitrate anion, yet not from an ammonium cation and a nitrate anion.

Also, I don't think it's possible for a nitro group bonded covalently to a benzene ring could revert back to a nitrate ion.

[roux]

I really don't see how if TNP can be formed by a hydrogen cation and a nitrate anion, yet not from an ammonium cation and a nitrate anion.

Also, I don't think it's possible for a nitro group bonded covalently to a benzene ring could revert back to a nitrate ion.

[kingspaz]

'I really don't see how if TNP can be formed by a hydrogen cation and a nitrate anion'

Roux, this is not how it works. The mechanism of nitration for phenol relies on the formation of the NO2+ species. This species is noramlly generated by the interaction of HNO3 and H2SO4. It can then take part in electrophilic substitution of the hydrogens of phenol on positions 2,4 and 6, since these are the positions activated by the -OH groups presence on te benzene ring. This is a common reaction mechanism covered in any good organic chemistry text book.

[kingspaz]

'I really don't see how if TNP can be formed by a hydrogen cation and a nitrate anion'

Roux, this is not how it works. The mechanism of nitration for phenol relies on the formation of the NO2+ species. This species is noramlly generated by the interaction of HNO3 and H2SO4. It can then take part in electrophilic substitution of the hydrogens of phenol on positions 2,4 and 6, since these are the positions activated by the -OH groups presence on te benzene ring. This is a common reaction mechanism covered in any good organic chemistry text book.

[kingspaz]

'I really don't see how if TNP can be formed by a hydrogen cation and a nitrate anion'

Roux, this is not how it works. The mechanism of nitration for phenol relies on the formation of the NO2+ species. This species is noramlly generated by the interaction of HNO3 and H2SO4. It can then take part in electrophilic substitution of the hydrogens of phenol on positions 2,4 and 6, since these are the positions activated by the -OH groups presence on te benzene ring. This is a common reaction mechanism covered in any good organic chemistry text book.

[Blackout]

Adding ammonium nitrate to phenol will just yield a mix of AN and phenol with no reaction. I believe sulfuric acid acts as a catalyst, H+.

[Blackout]

Adding ammonium nitrate to phenol will just yield a mix of AN and phenol with no reaction. I believe sulfuric acid acts as a catalyst, H+.

[Blackout]

Adding ammonium nitrate to phenol will just yield a mix of AN and phenol with no reaction. I believe sulfuric acid acts as a catalyst, H+.

[The_Duke]

Adding ammonium nitrate to phenol will just yield a mix of AN and phenol with no reaction. I believe sulfuric acid acts as a catalyst, H+.

Blackout,
The sulfuric acid reacts with the Phenol to form Phenolsulfonic acid to which the nitro groups are later introduced with the help of heat as a "catalyst", each addition of a new nitro group to the benzene ring requiring a higher reaction temperature than the previous.

Sulfuric acid DOES NOT act the way you are suggesting by simply donating “H” ions to the reaction like it does for AP.

[The_Duke]

Adding ammonium nitrate to phenol will just yield a mix of AN and phenol with no reaction. I believe sulfuric acid acts as a catalyst, H+.

Blackout,
The sulfuric acid reacts with the Phenol to form Phenolsulfonic acid to which the nitro groups are later introduced with the help of heat as a "catalyst", each addition of a new nitro group to the benzene ring requiring a higher reaction temperature than the previous.

Sulfuric acid DOES NOT act the way you are suggesting by simply donating “H” ions to the reaction like it does for AP.

[Sylla]

Mixing phenol and ammonium nitrate will just yield nothing. But there are many other ways to produce ammonium picrate.

Some times ago I successfuly produced it in gaseous-solid phase which is of great interrest since he who want ammonium picrate doesn't have to boil off a solution of picric acid and ammonium hydroxide.

Basically, once you have dried picric acid you suspend it over a stream of dry ammonia and after a few minutes you will notice a full color change from pale yellow to bright yellow-orange.

The main problem with picric acid is to get it dry when you make it from sulfuric acid. I recommend preparing a saturated solution of potassium or sodium picrate by adding potassium/sodium carbonate to picric acid in a few ml of water until no CO2 evolves anymore. Then, add water until everything is dissolved. Then, add the correct amount of conc HCl so that only picric acid is formed and the potassium hydrogenosulfate stay in the solution. Filter the picric acid, wash it a few water and let dry.

You will notice that the new crystals are only slightly soluble in acetone and the ammonium picrate made from it detonate by flame. The crystals loose their property to detonate by this mean after a few days. This is probably due to a modification in the structure of the molecule to a more energetic form as it happens with TNT and styphnic acid (the famous "red" forms).

No tests have allowed me to guess the formation of a new compound so it should be plain ammonium picrate...

But still, you will always need sulfuric acid to make trinitrophenol (which is not pure picric acid).

[The_Duke]

You will notice that the new crystals are only slightly soluble in acetone and the ammonium picrate made from it detonate by flame. The crystals loose their property to detonate by this mean after a few days. This is probably due to a modification in the structure of the molecule to a more energetic form as it happens with TNT and styphnic acid (the famous "red" forms).

Yes, the different forms are called Keto-Enol tautomers, very interesting stuff.

You can read more from Wikipedia; Keto-enol tautomerism (http://en.wikipedia.org/wiki/Keto-enol_tautomerism)