Visible light-mediated synthesis of 1,3-benzothiazoles: A comprehensive review

Photoredox catalysis has emerged as a powerful tool in organic synthesis, revolutionizing how chemists approach challenging bond-forming reactions. The importance of 1,3-benzothiazoles lies in their diverse roles in medicinal chemistry, materials science, and industrial applications, due to their stability, bioactivity, and versatility as building blocks. This review represents the most comprehensive work to date on photochemical methods for synthesizing 1,3-benzothiazoles, covering developments in this field from 2009 to 2024. It is organized by the types of starting compounds and discusses synthetic strategies for the target compounds alongside proposed reaction mechanisms. Notably, many established light-driven methods are photocatalyst-free and typically conducted under visible light (CFL, white, green, or blue LED) at room temperature. By exploring a range of synthetic methods, this review not only deepens our understanding of benzothiazole synthesis but also inspires possibilities for future advancements. We hope this review will motivate chemists to pursue new, environmentally friendly methods for synthesizing these and related biologically significant sulfur heterocycles.