Visible Light-catalyzed Radical Addition And Cyclization Of Glycine And 1,3-enyne To Construct Polysubstituted Pyrroles

Pyrroles,an important class of five-membered nitrogen-containing heterocyclic compounds,are widely present in biologically active molecules and are useful building blocks in natural products and materials science.The construction of pyrrole compounds has aroused a research upsurge in the field of organic synthetic chemistry,and it is very important to develop novel,effective and convenient synthetic strategies.However,there are relatively few reports on the synthesis of valuable and highly functionalized3-azaarylpyrroles,probably due to the difficult synthesis of starting substrates or the limited tolerance of reactive functional groups when the corresponding positions of pyrroles are substituted by aza compounds.Visible light-driven organic transformations have attracted extensive attention due to their mild reaction conditions,green environmental protection,and simple process.Based on the advantages of visible light catalysis and the importance of the pyrrole framework,we propose a functional group-directed strategy based on the radical process by exploiting the electronic properties of azaarenes and the high reactivity of radicals.Under the photoredox catalytic system,we obtained a series of valuable 3-azaarenes-substituted multi-substituted pyrroles.The reaction has the advantages of simple and easily available raw materials and high synthesis efficiency.Since the types of azaarenes and other substituents can be easily changed,this reaction has well functional group compatibility and a wide range of substrates,up to 81examples.Controll experiments and computational simulations of density functional theory（DFT）explain the reaction mechanism and the important role of Na H₂PO₄ as an additive.