Sciencemadness Discussion Board

How selectively remove Boc group (compound also has a phthalimide group)?

Romanosow - 14-10-2014 at 03:34

Can somebody help me? In my compound i have three phthalimide and Boc-amine groups. How i can remove the Boc group from my compound?

Chemosynthesis - 14-10-2014 at 10:42

Could you please post the SMILES of your chemical in question? We can use [SMILES.] and [/SMILES.] code without the periods inside brackets. I would suggest trying Zn/HCl.

edit
If that doesn't work, perhaps AcOH in EtOAc, though I don't get RSC pubs or know your substrate so this may not be appropriate.
J. Chem. Soc., Chem. Commun. 1979, 495-510



[Edited on 14-10-2014 by Chemosynthesis]

AvBaeyer - 14-10-2014 at 20:52

The standard reagents for removing Boc groups are anhydrous trifluoroacetic acid and 4 M HCl in ethyl acetate (anhydrous), both reagents being used at or below room temperature. The first gives the TFA salt, the second gives the HCl salt. The phthalimide should be stable to both reagents. Check out one of the protecting group books widely available to those who look.

AvB

Romanosow - 19-3-2015 at 00:27

Thanks! I solved my problem using TFA in dichlormethane with 5% water. 4M HCl also work, but forms some byproducts.