Heterocycle Synthesis via Decarboxylative Cyclization Methods

Carboxylic acid compounds are important structural units that exist widely in nature; the only byproduct in the decarboxylation process is carbon dioxide, which is non‐flammable, non‐toxic, and easy to remove. Therefore, decarboxylative reactions are of great importance in synthetic chemistry. Heterocyclic compounds are important backbones that constitute a variety of biologically active molecules; therefore, research into the development of new synthetic tactics for heterocyclic derivatives based on decarboxylative cyclization is of great interest. In this paper, we describe metal‐catalyzed, visible light‐driven, electrochemically enabled, decarboxylative cyclization reactions, as well as other types, that have been rapidly developed in the past five years; moreover, for some of these methods, we discuss the scope of their application and the mechanism of the reaction.