A few days ago, when I contacted the sales person from D-L Chiral
chemicals who is selling tartaric acid derivatives as resolving
agents, if they have resolving agents for  acids, he said their
tartrates can also be used for that purpose. I want to know can acidic
resolving agents (such as D or L dibenzoyl tartaric acid) be used to
resolve an acidic compound?

In principle, yes, as you're introducing a measure of
diastereoselectivity into the pot, and the two diastereomers may have
sufficently different properties to enable easy separation.

Usually however, you tend to use chiral bases, like brucine or
sparteine to resolve acids, if you want I can try and dig out some
references from the literature addressing this sort of point.

Stephan

Stephan,  I asked the guy from www.dlchiral.com to give me a
literature, he showed me this < J. chem. Soc. Chem. Commun. 1996,
1983>. If you have high interests to dig this topic (using chiral acid
to resolve racemic acids), please do so.  BTW, why don't you answer
the question and get paid?.

If only it were that simple (getting paid). Unless google have changed
their model, and I've missed it, only select accounts can act as
official answerers and get paid for answering questions. The relevant
link <URL:http://answers.google.com/answers/faq.html#becomeresearcher>
seems not to have changed for over a year or so.

The paper you've been cited looks OK, although for some reason my
authenication at the RSC site isn't working at present (so I can't see
the fulltext). Initially I thought that the tartrates may interact
though the hydroxyl groups and form selective bonds or complexes in
that part of the coordination sphere, but as the compounds mentioned
are derivatised there I'm not sure if this is the best way forward.

I'll try again later to see if I can get the paper :)

Fogassy seems to have done quite a bit of work in this area, so probably knows best.

Dear Sir,

We regularly manufacture and supply Tartaric Acid based Resolving Agents namely,

1. Di-para-Toluoyl-L-Tartaric Acid
2. Di-para-Toluoyl-D-Tartaric Acid
3. Dibenzoyl-L-Tartaric Acid
4. Dibenzoyl-D-Tartaric Acid

Purity and Optical resolution of above compounds are very important
criteria to select a supplier for resolving agents.The material is
hygroscopic in nature so, prolonged storage should be avoided.

More details can be provided if required.

Thanks

Sandip Shah