1,1′-Carbonyldiimidazole and Mechanochemistry: A Shining Green Combination

The application of mechanical forces to enable a chemical reaction, also known as mechanochemistry, is actually experiencing an impressive renewal of interest among the chemists community. One major advantage of this approach in organic synthesis lies in the possibility to run essentially solvent-free reactions. In recent years, some research groups have combined these types of solvent-free processes with the use of an eco-friendly reagent: 1,1'-carbonyldiimidazole (CDI). Thus, a wide range of molecules, including carboxylic acids, amines, and alcohols, could react efficiently with CDI under ball-milling conditions. By providing a vast array of products (amides, carboxylic acids, esters, ureas, hydantoins, etc.) in an efficient, fast, user-friendly, and green manner, this approach presents all the prerequisites to soon become a first choice methodology for all organic chemists. The reasons for the past and future successes of this combination are summarized, analyzed, and discussed herein.