BC orgo- Why are amines soluble in the organic layer?

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pedtoothdoc

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quick question, I was watching mikes video on acid base extraction and he talks about extracting a carboxylic acid from an amine and says that you should deprotonated the carboxylic acid so it moves to the aqueous layer and then the amine should separate into the organic layer. I was confused as to why the amine would separate into the organic layer. I though that since they are basic and can hydrogen bond, they too should move into the aqueous layer. Any explanations would be greatly appreciated! :)

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And why are protonsted carboxylic acids separated into the aqueous layer? They have -oh bonds that should form h bonds with water, right?
 
the way i always think of it is, carboxylic acids are "acids" (have acidic protons) and are water soluble. On the other hand, Amines do not have acidic protons, and amines are known to be very strong bases in o chem. (they also have R groups which outnumber the nitrogen and are nonpolar in nature, thus another reason amines aren't usually very water soluble)

as you can deprotonate a carboxylic acid and dissolve it in polar solution, you cannot do the same with an amine. Since you can isolate your acid in the polar solution, you have "extracted" it from your basic, organic solution containing the amine with its non polar R-groups. you have now separated your CA and amine into two distinct solutions and these can be separated in separate test tubes with a pipet.

I hope this helps!
 
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