Sciencemadness Discussion Board

citric acid and its products

underground - 17-11-2013 at 22:34

I was wondering if it is possible to do a tetranitrate salt of citric acid (Attachment) as it is going to have 4 hydroxyl groups.

1.JPG - 20kB

[Edited on 18-11-2013 by underground]

DubaiAmateurRocketry - 17-11-2013 at 23:11

I wonder if You can make the COOH to become C(NO2)3 by HNO3/H2SO4.

dangerdog - 17-11-2013 at 23:58

The structure you have drawn is not a salt but the ester(s)

underground - 18-11-2013 at 00:17

Quote: Originally posted by dangerdog  
The structure you have drawn is not a salt but the ester(s)


Yes, you have right, i will correct it

[Edited on 18-11-2013 by underground]

Metacelsus - 18-11-2013 at 06:56

No, what you drew is not an ester. It's an acyl nitrate.

And also, I doubt you will be able to form a stable nitrate salt of (protonated) citric acid.

underground - 18-11-2013 at 09:30

Quote: Originally posted by Cheddite Cheese  
No, what you drew is not an ester. It's an acyl nitrate.

And also, I doubt you will be able to form a stable nitrate salt of (protonated) citric acid.


So any help should be really welcome

Praxichys - 18-11-2013 at 12:49

Acyl nitrates are very unstable species and only exist in equillibrium with their hydrolosys products.

http://pubs.acs.org/doi/abs/10.1021/jo00912a020

In that paper, a mixture of acetic anhydride and 99% HNO3 were combined, and as a solution they behave like acetyl nitrate.

Since "citric anhydride" still has a hydroxyl and since water reverses the reaction, combined with the oxidizing nature of pure HNO3, I will venture to guess it will be nearly impossible to prepare the tetranitrate ester of citric acid. Even if it was prepared, it would rapidly become unusably hydrolyzed in air.

Boffis - 18-11-2013 at 16:58

Citric acid only contains one OH group so I think that the best you can hope for is a mono-nitrate ester, which I have not heard of but check out Beilstein and see if its there.

However, I don't hold out much hope because conc sulphuric acid converts citric acid to so called acetone-dicarboxylic acid (there are numerous references to this on this web site and Org. Syn.) and fuming nitric acid oxidizes and nitrate the latter via a complex series of reaction into furoxan-dicarboxylic acid or rather better the diethyl ester of acetone-dicarboxylic acid to the diethyl ester of furoxan-dicarboxylic acid (I can provide quite a few reference here too if anyone is interested). The same product can be obtained by nitration ethyl acetoacetate. One has to wonder what you would get nitrating triethyl citrate (OTC cosmetic ingredient)

underground - 18-11-2013 at 22:11

Quote: Originally posted by Boffis  
Citric acid only contains one OH group so I think that the best you can hope for is a mono-nitrate ester


What do you mean, i can see four

2.JPG - 8kB

dangerdog - 18-11-2013 at 22:57

Quote: Originally posted by underground  
Quote: Originally posted by Boffis  
Citric acid only contains one OH group so I think that the best you can hope for is a mono-nitrate ester


What do you mean, i can see four



There is only 1 OH group, the others are carboxylic acids.

Boffis - 19-11-2013 at 17:07

Thank you Dangerdog! At least there one switched on chemist out there.

The "OH" on the carboxylic acid groups act as a discrete unit, as though the two oxygens are identical; presumably the hydrogen is free to move between two.

underground - 19-11-2013 at 22:19

Quote: Originally posted by dangerdog  

There is only 1 OH group, the others are carboxylic acids.


Really interesting, i did not know that, so you have right, there is only one OH group that you can nitrate!!

3.JPG - 6kB

underground - 19-11-2013 at 22:25

Dangerdog it looks like there are several bonds that they can be nitrated except OH groups, like from toluene to trinitrotoluene, but why only those 3 C-H groups can be nitrated and the rest of them not ?

Also what else kind of ponds can be nitrated ?

[Edited on 20-11-2013 by underground]

4.JPG - 35kB

DubaiAmateurRocketry - 19-11-2013 at 23:03

Quote: Originally posted by underground  
Dangerdog it looks like there are several bonds that they can be nitrated except OH groups, like from toluene to trinitrotoluene, but why only those 3 C-H groups can be nitrated and the rest of them not ?

Also what else kind of ponds can be nitrated ?

[Edited on 20-11-2013 by underground]


It can,

http://en.wikipedia.org/wiki/Hexanitrobenzene

C6H3(NO2)3 → C6H3(NHOH)3 (partial reduction)
C6H3(NHOH)3 → C6(NO2)3(NHOH)3 (nitration)
C6(NO2)3(NHOH)3 → C6(NO2)6 (oxidation)

However you need different routes.

underground - 19-11-2013 at 23:48

Quote: Originally posted by DubaiAmateurRocketry  
Quote: Originally posted by underground  
Dangerdog it looks like there are several bonds that they can be nitrated except OH groups, like from toluene to trinitrotoluene, but why only those 3 C-H groups can be nitrated and the rest of them not ?

Also what else kind of ponds can be nitrated ?

[Edited on 20-11-2013 by underground]


It can,

http://en.wikipedia.org/wiki/Hexanitrobenzene

C6H3(NO2)3 → C6H3(NHOH)3 (partial reduction)
C6H3(NHOH)3 → C6(NO2)3(NHOH)3 (nitration)
C6(NO2)3(NHOH)3 → C6(NO2)6 (oxidation)

However you need different routes.


This is benzene, not toluene

What about octonitronaphthalene

[Edited on 20-11-2013 by underground]