Navigating the functionalization of unactivated alkenes via visible light photocatalysis

Direct functionalization of unactivated alkenes has emerged as a highly effective strategy for the rapid construction of multi-functional, complex molecular architectures from simple, abundant chemicals. This area of research has garnered increasing attention and continues to be a focus of contemporary chemistry. Recent years have witnessed substantial advancements driven by the discovery of photocatalysis and the expansion of activation strategies, which have led to the discovery of novel transformations and the refinement of established reactions. In this review, we provide a comprehensive overview of the visible-light photocatalytic functionalization of unactivated alkenes, with a particular emphasis on key reactions and mechanistic insights into transformations via hydrofunctionalization, difunctionalization and functionalized alkene retention. Furthermore, we discuss the recent progress, ongoing challenges and emerging opportunities in this significant field, highlighting the synthetic utility and potential for future applications.