Sciencemadness Discussion Board

Workup is degrading chemical?

Xylitol - 11-8-2018 at 00:57

So I've done this reaction several times to produce the chemical Emylcamate:

Trifluoroacetic acid, Sodium Cyanate, and 3-methyl-3-pentanol react in DCM to form Emylcamate (3-methyl-3-pentanol carbamate).

I won't go into too many details unless they may prove necessary later.

Anyway, here is my problem. It seems like I was only able to successfully produce the chemical twice, but most of the times have failed during the workup. The problem is that as soon as any base (I was using NaHCO3) is added to neutralize any excess acid, it ends up reacting with the chemical itself to form something else. I can see the little crystals flying apart as they react with the base. The same thing will happen with even just water alone.

Sometimes I get lucky and I think this is when I add the exact right proportions of the reactants and this way, I do not work up at all and just proceed to crystallization in ethanol and water and it works fine. The problem is that this is nearly impossible to achieve.

I want to know if I am doing something wrong because I want to be able to do the proper workup if necessary and not have it degrade the chemical.

Sulaiman - 11-8-2018 at 02:23

Is it that your product will not crystallise at low pH
or that your product does not exist at low pH ?

unionised - 11-8-2018 at 03:35

If the material is unstable in the presence of water, how could it ever have been used as a drug?