Microwave-Assisted Synthesis of Acyclic Imides

Abstract

Imides are an important class of compounds found in the structure of many biologically active and natural compounds. Imides are also important starting materials used in the synthesis of many heterocyclic compounds. Therefore, the synthesis of these compounds has attracted considerable attention and several innovative methods have been developed. Herein, the synthesis of acyclic imides has been reported from nitriles and carboxylic anhydrides in the presence of catalytic amounts of p-toluenesulfonic acid (PTSA) or H2SO4 under microwave irradiation. The reaction has proceeded in better yields with PTSA. When sulfuric acid was used, the product was obtained in lower yields since the degradation was increased. This new microwave-assisted method is compared with conventional heating, and the other methods, reported in the literature. The main advantages of this procedure are shorter reaction times, easier work-up, and good yields.