Carbodiimides activate carboxyl groups to form highly reactive O-acylisourea intermediates. These intermediates can then react with amines to form stable amide bonds. The general process involves three main steps: 1. Activation of the carboxyl group by the carbodiimide. 2. Formation of the O-acylisourea intermediate. 3. Reaction of the intermediate with an amine to form an amide bond, releasing urea as a by-product.
