Sciencemadness Discussion Board

turn calcium 3-hydroxy-3-methylbutyrate into 3-hydroxy-3-methylbutanoic acid

orgcstudent - 20-4-2014 at 06:50

Hello, I have spent some time on this forum and it has helped me before in the past. I have some questions about a reaction, sorry if this has already been covered :)



I want to turn calcium 3-hydroxy-3-methylbutyrate into 3-hydroxy-3-methylbutanoic acid.


I've found out that this could happen with a "single substitution reaction" by adding an acid with a pKa lower than 4.8. but Ive heard the HMB free acid itself is likely to condense to undesirable beta-methylacrylic acid. Is this true, can it be avoided. If so how? Also would tartaric acid be the best acid to use? I have access to a pretty wide range of acids that I could use so if tartaric acid isnt best, what would be?


Any info or links to something helpful will be appreciated, thanks!!

orgcstudent - 20-4-2014 at 16:16

hhm?? I should have put this in O. chem section.

[Edited on 21-4-2014 by orgcstudent]

thesmug - 20-4-2014 at 16:39

Yes

Crowfjord - 20-4-2014 at 16:46

This probably should have gone in beginnings, but here is my take:

If I were to try this, I would make a water solution of the calcium salt and acidify with dilute (1 or 2 M) HCl, keeping the reaction cool, with stirring. I don't think that elimination would be a big deal, but I could be wrong. This is why we experiment! :)

As for isolation, I'm not sure. Is the acid water-soluble?

orgcstudent - 20-4-2014 at 17:38

OK.. I know I can experiment and I will. I was just wondering if anyone has any insight on it. What about it condensing to beta-methylacrylic acid?


Thanks for the input :D

[Edited on 21-4-2014 by orgcstudent]

Crowfjord - 20-4-2014 at 17:58

The "condensation" you mention is actually an elimination or dehydration reaction, which I mentioned. I don't think that it should be much of an issue, as long as temperatures are kept low and dehydrating conditions are avoided. You might be able to extract with a solvent like ethyl acetate, but I'm not sure, as I can't find solubility data at the moment.

orgcstudent - 20-4-2014 at 18:02

Thank you so much.

orgcstudent - 20-4-2014 at 18:05

Use ethyl acetate to extract the 3-hydroxy-3-methylbutanoic acid from the water after it is acidified?

orgcstudent - 20-4-2014 at 18:09

Im not sure if its water soluble.

Crowfjord - 20-4-2014 at 18:09

That's the idea, yes. Then evaporate the ethyl acetate to recover the acid. This is, of course all based on the assumption that the acid is more soluble in ethyl acetate (or maybe another organic solvent) than acidic water.

orgcstudent - 20-4-2014 at 18:23

:)

[Edited on 21-4-2014 by orgcstudent]

Crowfjord - 20-4-2014 at 18:41

Told by whom? Is this a school assignment? It probably has to do with pKa, but it's hard to know without more information.

Etaoin Shrdlu - 20-4-2014 at 18:43

Where are you being told this? One of those is the right acid to use, or all of them are? If it's the latter I'd guess so the end product would still be food-grade. Please don't sell this to people.

orgcstudent - 20-4-2014 at 18:50

Im looking for patents and more info online but there really isnt much.

[Edited on 21-4-2014 by orgcstudent]

Etaoin Shrdlu - 20-4-2014 at 19:07

If it's schoolwork complete with a list of acids to pick from, they should have given you all the information you need to solve the problem already. Go back to your books.

orgcstudent - 20-4-2014 at 19:10

:P

Etaoin Shrdlu - 20-4-2014 at 19:15

Quote: Originally posted by orgcstudent  
:P


"HMB free acid itself is likely to condense to undesirable beta-methylacrylic acid"

Alas there is no "dirty look" smiley.

orgcstudent - 20-4-2014 at 19:28

Thank you :)




[Edited on 21-4-2014 by orgcstudent]

[Edited on 21-4-2014 by orgcstudent]

Bert - 20-4-2014 at 21:24

Kind of like this thread?
Quote:



Remove calcium from calcium beta-hydroxy-beta-methylbutyrate

« on: April 08, 2014, 02:33:55 AM »

Does anyone know of a way to separate the calcium part from calcium beta-hydroxy-beta-methylbutyrate (calcium HMB) so that we would be left with β-Hydroxy β-methylbutyric acid (HMB free acid)?

Calcium HMB is a sport supplement, but recent research has shown that the free acid form of HMB is superior. Therefore I would like to find out if it's possible for a home chemist to perform the conversion.

To be clear, to go from this:


Calcium 3-hydroxy-3-methylbutyrate: http://en.wikipedia.org/wiki/Calcium_beta-hydroxy-beta-methy...

to this:


3-hydroxy-3-methylbutanoic acid: http://en.wikipedia.org/wiki/Beta-Hydroxy_beta-methylbutyric...

It was suggested to me that citric acid might be used, but I don't have a clue if that would work.

Can anyone help?




There's no chance you would sell a home made organic chemical to body builders who would consume it, is there? Because a number of people asking how to produce popular chemicals such as dinitro phenol have had their threads sent to detritus recently.

If it's purely for your personal use, might suggesting "sensible diet & reasonable exercise" convince you to not to home manufacture biochemicals to mess with your OWN metabolism/endocrine system?

I know that last suggestion sounds old fashioned- "I'm so old, I can remember when I wasn't behind the times!"

[Edited on 21-4-2014 by Bert]