Flash chromatography is a chemical separation technique used to purify chemical mixtures. Because it is a purification technology, the process is also referred to as flash purification.
Challenging separations, we all have faced this vexing problem. You synthesized your compound, analyzed it, and know your molecule is in there, based on LC-MS or TLC. Then, you do some method development using a silica TLC plate and see a major spot with some minor, early-eluting impurities. You think that the purification will be easy only to find that your “purified” compound has some co-eluting impurities. Now what? Should you change solvents or change stationary phase?
In this post, I will show how changing the column media but keeping the same solvents removed a co-eluting impurity in one of my reaction mixes.