Solvent-free preparation of amides from acids and primary amines under microwave irradiation

Synthesis of amides via pyrolysis of the salts obtained by mixing neat primary amines and carboxylic acids were realized under solvent-free conditions within short times and appreciable yields under microwave activation. The evident specific non-thermal microwave effects are attributed to polarity increase during the course of the reaction, due to development of a dipole in the transition state.