From: Roux, Stephane (RouxS$##$corning.com)
Date: Wed Apr 26 2000 - 10:59:41 EDT
Hi,
Anionic weak-exchanger resin will do the trick if you need a pure sample.
first equilibration with NaCl,
then sample elution with NaCl or CH3CO2-Na+
advantage : separation of mono acids from diacids,
finally : extraction at pH 1 or desalting with sephadex G-10 from sigma (elution with distilled water)
Stephane Roux
> ----------
> De : Micha> ł Kędzierski[SMTP:micked$##$ichp.waw.pl]
> Date : mercredi 26 avril 2000 16:41
> A : Multiple recipients of list orglist
> Objet : ORGLIST: Bisarylmethanes from deactivated aromatic compounds
>
> Hello,
>
> I am looking for the answers to the following questions:
>
> 1. Does anyone know some convenient method for preparation of
> bisarylmethanes
> of general formula X-Ar-CH2-Ar-X, where X is an deactivating,
> meta-directing group
> (like sulfonic or phosphonic acid). ?
>
> The second question is relative to the first one:
>
> 2. Searching Beilstein I have found some examples (e.g. for benzoic
> acid), where reaction with formaldehyde
> leading to bisarylmethanes was carried out in the concentrated
> sulfuric acid medium.
> The products were precipitated by the addition of water.
> But how to separate water soluble bisarylmethanes containing
> phosphoric or phosphonic acid groups
> (quite strong acids , pKa about 1 and 2, respectively) from its
> solutions in concentrated sulfuric acid ?
>
>
> Thank you in advance for any suggestions
>
> Michal Kedzierski
> Industrial Chemistry Research Institute,
> ul.Rydygiera 8, Warsaw, Poland
>
>
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>
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