Question

what is the purpose of each of the extractions (washings) the crude product? In other word, what is removed upon washing with (a) water (b) sodium bicarbonate and finally (c) ammonium chloride. The experiment I did is amide synthesis from carboxylic acid and amine and using EDCl with catalyst DMAP and DMF. By doing the extraction. I dilute my reaction mixture with 40 ml of water, pour the contents into separatory funnel. Then add approximately 20 mL of ethyl acetate and cap the funnel and do the extraction. do this step three times and collect the aqueous layer and organic layer. and then wash organic layer by using sodium bicarbonate and ammonium chloride. This is experiment detail.

Answer 1

PAGE NO Water Water can potentially remoue water soluble impurities from on Organic lawn The following are the common materiales that can be removed with a water wash unconsumed acid or base many ionic salts, and compound that can hydrogen bond with water I have an Oxygen or nitrogen atom) 00 Sodium bicarbonate (1) Remowing alkaline material Sometimes the organic layer, when derived from acidic solution should be washed with soduim Bicarbonate. salt formed in this reaction is water soluble and will be flushed out with aqueous phase 2) Keeping the ag. A organic layer separat as sodium bicarbonate helps to decreasi the solubility of Organic layjer into aqueous laya satwiated ionic solution may be used to dec: The solubility of Dug: comp in aqueous layer, allowing - more of compound to dissolve in organic layer 9f desired polt can hydrogen bond with water I is relatively small, it may be difficult to keep it in organic layer when partitioning, with ag. phase

PAGE NO Howeverequilibrium can fauowe the organic layes of all aqueous washes contain high cone of cons like NHull.