Chemical Forums

Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: redfox on April 03, 2008, 09:03:19 AM

Title: Theobromine - why does it dissolve in acid or base, but not water?
Post by: redfox on April 03, 2008, 09:03:19 AM

The title pretty much says it all.

Theobromine dissolves easily in acid or base, but it poorly soluble in water
at pH 7.

Is it because it's zwitterionic and needs something that is a definite electron
withdrawing/donating group to attach to it?

That sounds about right, but I'm not entirely sure.

Thanks! :)

Title: Re: Theobromine - why does it dissolve in acid or base, but not water?
Post by: Arkcon on April 03, 2008, 09:57:22 AM

Can you look at the structure, and make some guesses.  Maybe post a drawing as a .gif  and talk about it?

Title: Re: Theobromine - why does it dissolve in acid or base, but not water?
Post by: redfox on April 06, 2008, 03:01:57 PM

Ok, here's the structure. There are no atoms requiring addition or removal of electrons so it won't easily react with something neutral. It'll only react when something comes along that substitutes or adds somewhere there's a double bond. Is there anything else to say about it? What are technical terms I should be using instead of what I've just said?
I'm a bit new at all this:(

Title: Re: Theobromine - why does it dissolve in acid or base, but not water?
Post by: ARGOS++ on April 07, 2008, 08:28:58 AM

Dear Redfox;

With your Assumption of your Question: “ZwitterIon” you are very close, even if the term “ZwitterIon” in this case may not be the absolute adequate notation.

The “Imide ‘Proton’” has a quite acidic character, and also one of the other “Amines” can be protonated to a certain amount.
For that you may read on:   "Imide (http://en.wikipedia.org/wiki/Imide)”.
(Also the same Page in German.)

And for the quite “stronge” Relatedness to “Imidazoles” see on: "Imidazole (http://en.wikipedia.org/wiki/Imidazole)”.

I hope it may be of some help to you.

Good Luck!
                    ARGOS⁺⁺