Sciencemadness Discussion Board

Decarboxylation of threonine or isoleucine for potentially useful solvent

Eddygp - 20-5-2018 at 07:28

First, this out of the way: why threonine?
1) two chiral centres of which one will be preserved.
2) the resulting product melts at under 2ÂșC so it would be a useful solvent.
The decarboxylation of threonine would afford (R)-1-aminopropan-2-ol as a single enantiomer.

My idea is that using this solvent to carry out certain reactions, a certain degree of enantioselectivity would be obtained. However, this effect would be very small (perhaps 10%ee at most).
However, most importantly beyond anything else is that the solubilities of different enantiomers would be different, which would allow recrystallisation of enantiomers from a racemic mixture. The effect might be rather small for some molecules, but I can imagine that if done sufficiently carefully, single enantiomers could potentially be separated.

What do you think? Would (R)-1-aminopropan-2-ol be useful as a solvent? And to what extent would it allow recrystallisation of enantiomers?

Just realised isoleucine would also afford a single enantiomer product with a wide liquid temperature range.

For any other aminoacid, the only way to preserve any chirality would be reduction and this is harder for home chemist purposes.

[Edited on 20-5-2018 by Eddygp]

Boffis - 25-5-2018 at 00:35

Hm, seems like a reasonalbe idea and there is plenty of information about decarboxylation of amino acids on this site. Why don't you have a go and let us know how you get on. I can see threonine being a bit of a problem at elevated temperatures with a tendency to cyclitize to a pyrazine derivative.