At the end of reaction, the mixture was containing a little water and my required compound, dissolved in it. As it was acidic (pH=3), i added aqueous solution of sodium bicarbonate to neutralize it but i could get pH=6, not pH=7. In order to extract my compound from this aqueous solution, i transferred it to a separating funnel and added ethyl acetate as my compound was also soluble in ethyl acetate.At the end of reaction, compound was not extracted appreciably by this method. Furthermore, compound is not soluble in any other solvent except in benzene. I would highly appreciate if you share your expertise for extracting my compound from aqueous solution of NaHCO3.
if your solvent is water and you cant extract with separating funnel you can use Rotary Evaporator.
Rotary Evaporator and Freeze drier work perfectly for aqueous solutions. If you want really get pure substance from the reaction you would want to do column separation or even HPLC. And after concentrate the fraction you collected
dear you have got your answers. if your compound is heat labile than don't use rotary evaporator, otherwise just dry your sample
Dear Maryam Khosravi and Anton Shekhov, I did use Rotary Evaporator but at the end, i got a mixture in solid state containing my required compound along with unwanted salts. So, neither use of separating funnel nor using rotary evaporator did pure my compound appreciably. Because both, my compound as well as salts, are water soluble and i am trying to pure my compound from these salts and the journey toward purity is not yet finished.
to separate from the salts you can even try Size Esclusion chromatography or preparative HPLC.
If your product is not a salt then sometimes you can trap the salts by filtering your compound, dissolved in an appropriate organic solvent, through a short plug of silica, trapping the salts on top of the silica while eluting your product.
I am somewhat confused by what you've written. At first you say it is dissolved in water, later you state it is exclusively soluble in toluene. Some structural information could be useful. If the compound contains acidic protons, try to add 1 M HCl till pH
carbon tetra chloride and benzene which one does not show association in organic phase, cold sod bicarbonate saturated soln used for that.
Disttled organic solvent after separation from aqueous phase.
finally , your compound remains separated .
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