Recent advances in the synthesis of indoles and their applications

Abstract

Indoles are very important heterocyclic scaffolds and they continue to attract substantial attention due to their presence in biologically active compounds, pharmaceuticals, agrochemicals, and functional materials. Therefore, there is a constant need to discover methods that allow for the production of indole molecules. This review thoroughly investigates the key advancements in the synthesis of indoles reported over the past two years (May 2023 to April 2025), emphasizing innovative methodologies that provide substantial conceptual breakthroughs. This review covers methodologies that enhance efficiency and enable divergent synthetic routes to access a variety of indoles, while also providing useful perspectives for their future applications. This review provides a comprehensive account of the recent literature. Notably, methodologies such as acid and base-promoted cyclizations, metal-catalyzed reactions, and photo- and electro-catalyzed techniques are examined for their significant contributions to reshaping the synthetic landscape of indoles. Through detailed exploration of these techniques, this review seeks to shed light on their underlying mechanisms, applications, and impact, thereby advancing the understanding of evolving strategies in indole chemistry.