I am doing a flash column with hexane. There are two overlapping spots in TLC even in Hexane (Rf ~ .4) , and as a result, I am getting mixture. I tried using a long column, but still some mixture comes.
I have tried cyclohexane solvent for the TLC, still the separation is not good.
Dear Saayak,
You can try reverse phase flash chromatography. Using water and ACN as mobile phase.
If you can't get pure product so you can used different buffer like Formic acid, TFA, Ammonium Bi-Carbonate.
Best of Luck.
Maybe you don't need lower elution power - try to play with selectivity by addition of some modif. to your eluent like THF or dioxane. Otherwise you need to change the stat. phase. Maybe there is no need to sqitch to RP ( does your analytes are soluble in water?). You can use NP with NH2 or CN stat. phases.
Regards
G
Hi Saayak,
if your desired compounds contain methoxy groups, you can accelerate them selectively by using THF in various amounts. That's an old trick but it works.
Regards
Markus
Hi Mr Vivekshinh,
Thanks for the answer. I currently so not have a RP flash column. Also, my compound is not soluble in water, its very nonpolar.
Hi Mr Halay,
Thanks for the answer! I have tried combinations of Hex:EtOAc, and only in Hex do I see the slight difference in Rf. DCM and methanol are all too polar and there seem no separation.
Saayak
Dear Mr Boczkaj and Mr Christ,
Thanks for the insight. I will try those conditions with THF and dioxane!!!
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