Chemistry Reference
In-Depth Information
diimidazole and imidazole is eliminated. Intermediate C then results from a second
addition-elimination step where imidazole adds to the resulting anhydride species,
and the group being eliminated decomposes to carbon dioxide and imidazole. This
sequence of events is illustrated below using arrow pushing.
Like the mixed carbonic anhydride (intermediate A from Problem 7(a)), the inter-
mediate imidazolide (intermediate C) is an activated carboxy group that can react
with amines to form amides. The addition-elimination mechanism, illustrated
below using arrow pushing, involves addition of an amine followed by elimination
of imidazole.
