i want to separate my product which is aromatic amine from acetic acid which is used as solvent . i used about 20ml of the acetic acid as solvent.
Acidify your reaction mixture with small excess of water solution of strong mineral acid /HCl, H2SO4.../. Aromatic amines /weak bases/ will form salts with the acid and are not volatile. Distill CH3COOH at moderate temperature and in a deep vacuum /Rotavap distillation/. Instead of rotavap separation of CH3COOH its extraction from the mixture with diethylether or THF may be an option.
Another approach dwells in neutralization of CH3COOH with dilluted NaOH and extraction of aromatic amines with diethylether, benzene or toluene, tetrahydrofurane etc.. Ionized sodium acetate will stay in its water solution and amines will pass into organolayer.
Good luck.
Note: if your amine are oxidation sensitive, work in an inert environment, e.g. N2
Acidify your reaction mixture with small excess of water solution of strong mineral acid /HCl, H2SO4.../. Aromatic amines /weak bases/ will form salts with the acid and are not volatile. Distill CH3COOH at moderate temperature and in a deep vacuum /Rotavap distillation/. Instead of rotavap separation of CH3COOH its extraction from the mixture with diethylether or THF may be an option.
Another approach dwells in neutralization of CH3COOH with dilluted NaOH and extraction of aromatic amines with diethylether, benzene or toluene, tetrahydrofurane etc.. Ionized sodium acetate will stay in its water solution and amines will pass into organolayer.
Good luck.
Note: if your amine are oxidation sensitive, work in an inert environment, e.g. N2
If you think, your aromatic amine will not get soluble in water then you can just try the precipitation in cold water, acetic acid will get soluble in water and your amine will precipitate out
A way could be to dilute with water and bring to ph 9, followed by extraction in organic solvent, and water removal with MgSO4....
Kindly remove the acetic acid from the reaction mixture under reduced pressure using rotary evaporator. Then add water and bring the pH about 8-9 by adding sodium bicarbonate slowly
Assuming that your aromatic amine is not water soluble, dilute your reaction mixture with diethyl ether (20 ml, or dichloromethane), then wash the reaction mixture with water several times (20ml x 3). As you know acetic acid is very soluble in water. Then wash the ethereal layer with sodium hydrogen carbonate solution once, water once, dry (MgSO4) and evaporate.
Remove the big part of acetic acid by distillation at rotavapor. when you will have few mL inside your flask, add water and ypur product should be precipitate.
Generally during grignard raection excess Mg is quenched by acetic acid. It can be applied for ur reaction as the Mg & Acetic acid react fast to form mag Acetate which is soluble in water.
Before that ensure ur product is not ppt as acetate salt.
aromatic compound is part of organic compound, and most of organic copound is volatile so for separation that aromatic compound with acetic acid can be carried out by distillation, then you can continue with extraction process with water solution for remove residual acetic acid, and for finishing to remove residual water you can use CaCl2
I agree with Suggestion from Luigi Grassi.
If you are okay with acetate salt then simply you can co-distill the reaction mass with toluene using rotavap
In my opinion the second suggestion from Prof. Rastislav Solar will be the best one for solving this problem.
If an amine is present in an acidic medium, it is most likely to be in the form of a salt of the acid. Neutralisation of the acetic acid with a strong base like NaOH will liberate the free amine. Now this amine can be nicely extracted with diethyl ether. Acetic acid, in the form of sodium acetate, will also remain in the aqueous medium.
Pass the mixture through a basic resin column which should be able to retain the acetate and release the amine for recovery
U can add magnesium , which will turn into magnesium acetate and can proceed for column.
Remove the acetic acid under reduced pressure and bring the pH to 7 followed by extraction with diethyl ether.
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