Amines Do Not Undergo Substitution or Elimination Reactions

Although amines, like alkyl hahdes, alcohols, and ethers, have an electron-withdrawing group bonded to an sp carbon, amines do not undergo substitution and ehmination reactions. 

Protonating the amino group makes it a better leaving group, but not nearly as good as a protonated alcohol, which is almost 14 units more acidic than a protonated amine. 

Therefore, unlike protonated alcohols, protonated amines cannot undergo substitution and elimination reactions. 

Although they cannot undergo substitution or elimination reactions, amines are extremely important organic compounds. The lone pair on its nitrogen allows an amine to react as both a base and as a nucleophile. 

Amines are the most common organic bases. We have seen that protonated amines have pK values of about 11 and that protonated anilines have pK values of about 5 (Sections 2.3 and 8.15). Neutral amines have very high pK values. For example, the pK of methylamine is 40. 

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