Etherification was carried out between aromatic -OH group and alkyl chloride in the presence of ethanolic KOH. The precursor is a bulky dye compound that consists of an aromatic -OH group and an ester group.
When the reaction stopped, I tried to remove the excess KOH by extraction. The product can only extracted by ethyl acetate (cannot be extracted by DCM, CHCl3, diethyl ether, toluene). However, strong acetic acid smell was detected in the extracted layer after the solvent was evaporated.
I tried to directly recrystallized the product in ethanol after the reaction, no crystal was formed but an oily layer emerged beneath the ethanol.
Is there any suggestion to remove these KOH and unwanted inorganic by-product after etherification?
one question:
why are you using ethanolic KOH when you could use a nonnucleophilic base like potassium carbonate? after reaction is done, potassium carbonate can be removed by water wash and your product can be extracted by Ethyl acetate
not quite sure about the acetic acid smell but if you are producing acetic acid somehow, acetic acid can be removed by rotavapping with hexanes (forms azeotrope).
If you have already done it, and now you need to remove it, you can try to use CO2 to convert KOH to KHCO3 which should precipitate in ethanolic solution and than you can wash it as Greg Petruncio recommended.
After reaction complete remove ethanol under reduced pressure and dilute with ethylacetoacetate. Inorganic will precipitate. Seperate out.
Keep your reaction mixture on ice bath and neutralised it with 5N HCl. After neutralisation you get separated layer. You may directly separate or you can extract it with ethyl acetate.
To remove the KOH from ethanolic etherification without using extraction method , neutralize the reaction mixture obtained after reflection by treating with 2N HCl to PH=7 , organic layer separates out.Extract organic layer with chloroform or dichloromethane. Removal of Organic layer under vacuum will give ether.
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