Ultrasound-promoted metal-catalyzed synthesis of heterocyclic compounds of medicinal interest

Abstract

In the last decade, sonochemistry has become an interesting field of research in both organic chemistry and pharmaceutical industry. It is well known that sonochemical effects are derived from a phenomenon known as acoustic cavitation, that is, the formation, growth, and implosion of microbubbles inside a liquid. These effects induce high temperatures (near 5000K) and very high pressures (around 1000 atmospheres) inside such cavities, while shock waves at the interface and bulk liquid are largely responsible for enhanced mass and energy transfers. By virtue of the effects mentioned above organic synthesis of heterocycles, assisted by ultrasound irradiation, constitutes a convenient way to accelerate and improve the synthesis of a great number of compounds with analgesic, antipyretic, antiinflammatory, antibacterial, and fungicidal properties. Moreover, it is important to mention that other heterocyclic compounds have been used in cancer treatment, cardiovascular disease, type 2 diabetes, migraine, and anxiety; also can be used as anticonvulsants, sedatives, and hypnotic agents. The present chapter is focused on ultrasound-promoted metal-catalyzed synthesis of heterocyclic molecules reported between 2000 and 2019.