Harnessing Photochemistry in Natural Product Synthesis: From Strategy to Applications.

Photochemistry and total synthesis are deeply rooted in the history of organic chemistry, each developing independently while also intersecting frequently. Indeed, mild reaction conditions, versatility of transformations, and complementary selectivities to thermal methods make photochemistry an especially powerful tool for the synthesis of complex target molecules. In this Review, we highlight recent examples of total syntheses (from 2020 to 2025) featuring photochemical reactions as pivotal steps. Although the application of photochemistry in total synthesis has been consistently reviewed throughout the past decades, we feel that the wider emergence of photocatalytic methods, together with the continued importance of certain direct irradiation approaches, warrants its own discussion. We hope that our analytical approach and strategic insights will help us to identify cases where photochemical reactions could prove useful, thereby further encouraging their use in total syntheses.