jcbradley's blog

23 Mar

Ideas on disappearing furan in TFA?

Published by jcbradley

We have a problem in synthesizing our anti-malarials that could use some feedback from some organic chemists:

Ever since we isolated our Ugi products, we've been trying to cyclize them to the diketopiperazines. As described by Hulme, we are trying to effect an intramolecular transamidation catalyzed by trifluoroacetic acid (TFA). Instead of dichloroethane we are generally using CDCl3 so that we can monitor the reaction by NMR.

The first step of removing the boc group seems to proceed very smoothly, with the appearance of t-butyl trifluoroacetate at 1.61 ppm within a few minutes or hours, depending on the concentration of TFA. Here is a H NMR from Khalid's EXP070, 13 min after addition of 50% TFA in CDCl3 showing complete deprotection:

11 Feb

Let's work together

Published by jcbradley

I have an organic chemistry lab available to carry out some of the synthetic work that needs to be done. As of this week our lab notebook is available online here http://usefulchem-experiments1.blogspot.com and discussions of our synthetic strategy is made public here http://usefulchem.blogspot.com

Our main focus is currently the synthesis and testing of anti-malarial agents. We would welcome input from the scientists on your team to help us contribute more effectively to this open science project.