What reaction results in the formation of an amide?

1 Answer
Sep 3, 2016

#RC(=O)X + 2H_2NR rarr R(C=O)N(H)R + HX*H_2NR#

Explanation:

As shown, this is the amine equivalent to the esterification reaction. An acid halide is treated with 2 equiv of amine, 1 equiv forms the #(O=)C-N# bond, the other equiv sops up the liberated #HX# as the ammonium salt. (If the amine were expensive, I could use just the 1 equiv. and use #Et_3N# as the base.)

Alternatively (and less likely) you may mean the formation of amido, #""^(-)NH_2# anions:

#2NH_3 rightleftharpoons NH_4^(+) + NH_2^-#.

This equilibrium operates in liquid ammonia, and is precisely equivalent to the acid/base equilibrium that water undergoes:

#2H_2O(l) rightleftharpoons H_3O^+ + HO^-#