Visible Light Induced Difunctional Hetero‐Annulation of Unsaturated C−C Bonds

Abstract

AbstractHeterocyclic scaffolds are beneficial structural architects in a wide range of pharmaceuticals, agrochemicals, biological and also functional materials. In this regard, several investigations have been performed to synthesize them. Among these, visible light‐induced difunctionalization cyclization strategy provides attractive solutions by adopting greener routes, breaking the monopoly of conventional thermal processes. A review on these methodologies is also desirable as unsaturated aliphatics, especially alkenes are one of the cheapest feedstocks available. They offer diverse options and modifications to generate different products, including heterocycles, which are highly sought after due to their applications in various sectors. To account for the advancements in this strategy, we summarized the visible light induced difunctionalization strategies that directly lead to the synthesis of heterocyclic scaffolds from unsaturated C−C bonds. We have categorized the relevant reaction schemes into four mechanistically distinct sections namely (i) Two component oxidative annulations (ii) Radical mediated annulations (iii) Polar radical crossover annulations and (iv) Three component oxidative annulations.