Light on the Horizon: Current Research and Future Perspectives in Flow Photochemistry

Synthetic organic photochemistry is a powerful tool for creating both natural products and molecules with high structural complexity in a simple way and under mild conditions. However, because of the challenges in scaling-up, it has been difficult to apply a photochemical reaction in an industrial process. Flow chemistry provides an opportunity for better control over the conditions of the reaction and, additionally, improved reaction selectivity and enhanced reproducibility. Taking into account that significant interest has focused on the use of flow photochemistry as a method for the synthesis of heterocycles and its applications in target-oriented synthesis over the past few years, the aim of this review is to highlight recent efforts to apply flow photochemistry methodology to diverse reactions as a greener and more scalable process for the pharmaceutical and fine chemical industries. Additionally, the review highlights future perspectives in the development of scale-up strategies, combining photochemical reactions in the continuous-flow multistep synthesis of organic molecules, which is of interest for scientists and engineers alike.