What is carbonyl diimidazole?

Carbonyl diimidazole (CDI) is a chemical compound with the formula (C3H3N2)2CO. It is a white crystalline solid that is used as a coupling reagent in organic chemistry. CDI is soluble in organic solvents and reacts with a variety of functional groups, including amines, alcohols, and carboxylic acids, to form amides, esters, and peptides. Its reactivity and stability make it a popular choice for peptide synthesis. It is also used as an acylating agent and a dehydrating agent in organic reactions. CDI may cause eye and skin irritation upon contact and should be handled with care.