I have general question, I am currently working HEDTA selective bromination on alcohol group but I have issuses in extracting, isolation and even analyzing the reaction by TLC because compound is only soluble in water at rt. So Please suggest me the exact reaction condition for TLC and product Isolation or literature on selective bromination in presence of acid and amine groups.
Re: Selective Bromination on HEDTA, organic reaction
Are you sure you're getting your product? If it's only soluble in water, how have you analyzed? Perhaps by diluting into methanol and putting on Mass Spec to confirm product peak formation?
What else have you tried for solubility? Perhaps DMF or acetic acid? Bromination should still work fine in those solvents. Bromination would form a mixed product in water if you're trying to brominate an alkene, for instance, because water is nucleophilic. DMF and acetic acid are not, but they are polar. I would try your product in those.
I've had things soluble in water before and I could do a TLC plate by letting the plate dry after spotting. I would dry it in a glassware oven or leave under a closed fume hood for overnight evaporation of the water. Depending on product stability, of course. Once the TLC plate is dry, you should be able to run it. If you can run it, you can purify it. Depending on yield needs, I've used preparative TLC before and gotten excellent purity but low yields. I was making interesting amides for medicinal purposes, so purity was my ultimate goal.
Lauren E. Ragle, PhD Chair-Elect | Chemical Society of Washington Assistant Professor | PBPM Program The George Washington University Pronouns: she/her/hers https://smhs.gwu.edu/postbac-premed/