ammonium isocyanate
Hazard to Others
Posts: 124
Registered: 13-7-2009
Location: USA - Midwest
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chiral resolution of L-alanine
Does L-alanine form enantiopure crystals that can be seperated out easily, or are more complicated techniques required to seperate out the opitical
isomers? If more complicated techniques are required, does anyone know of/ have a reference to such a procedure or an analogous one that may be
adaptable?
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garuda
a.k.a. Sauron
Posts: 17
Registered: 30-7-2009
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You seem confused.
L-alanine by definition is the natural amino acid
D-alanine is the other stereoisomer. thar does not occur in nature.
Neither needs to be resikved,
DL-alanine is the racemate and would need to be resolved.
So you night want to rethink your query
There are three methods of resoltion
1. Form a compound of the racemate with a isomer of a chiral compound, and you can now separate the two possible combinations into purer forms by
fractional crystallization.
2, Enzymatically separate the stereoisomers
3. Chiral chromatography.
It is rare that a racemate forms large crystals of isomers that can be separacted physically.
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ammonium isocyanate
Hazard to Others
Posts: 124
Registered: 13-7-2009
Location: USA - Midwest
Member Is Offline
Mood: sick
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What I meant was could racemic alanine be seperated out inot the D- and L- isomers. Sorry for the vagueness. I was particularly interested in
L-alanine because it is the naturally occuring isomer.
I found the answer to my query in the book Chiral Analysis (Marianna A. Busch, 2006). As it turns out, (R)-alanine will form distinct crystals in the
presence of a small amount of (R)-theonine. I know that the R- and S- notation is not always the same as the D- and L- one, but it isn't really
important because I don't have a particular use for the compound, just thought it would be kinda interesting to try.
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