Re: ORGLIST: borohydride reduction reaction workup

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From: support$##$cussyn.com
Date: Sun Jul 31 2005 - 16:04:57 EDT


Diogo,

One possible option is to use a strong cation exchange(SCX)
resin to effect 'catch and release' purification.
SCX columns and bulk resin are commercially available from
many sources and will selectively retain amine containing
compounds. This will allow you to selectively elute non-amine
compounds easily with methanol or another appropriate solvent
that the impurities are soluble in. Once you have rinsed out
the impurities you can liberate your amino sugar using dilute
ammonia methanol solution (~1-2M NH3 in MeOH), assuming of
course that your compound is non reactive or stable to dilute
NH3-MeOH. With some resins and amines you can also elute with
acidic solutions to give the amine salt after concentration.
Another option for liberating the bound amine is to elute
with a solution containing a volatile buffer in medium to high
concentration (Ammonium formate, acetate, etc....)

I highly recommend that you consult the manufacturers spec.
sheets for specific conditions, as the capacity and solvent
compatibility may be different from manufacturer to manufacturer.
The variety ofsize and binding capacity has worked well for
small to mediumscale purifications. There are many different
sizes of columns available. See the below links I have
attached for your convenience, this should give you a starting
point. A simple web search for SCX columns will provide you
with a variety of examples.

In cases where the non-amine impurities were otherwise
difficult to
remove, I have used the SCX columns repeatedly with great success!


Good Luck,

BJD


http://argonaut.biotage.com/products/analytical/isolute_spe/pdf/TN106_SCX_SCX-3_StrongCationExch_AqSample.pdf

http://www.biocompare.com/matrix/6659/Strong-Cation-SPE-Columns.html

http://saturn.bids.ac.uk/cgi-bin/ds_deliver/1/u/d/ISIS/20276626.1/ben/cchts/2002/00000005/00000003/art00004/B03BA56BA0B7A2AD112283807382AB5340C48C906D.pdf?link=http://www.ingentaconnect.com/error/delivery&format=pdf
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