Visible Light Catalyzed Intermolecular [3+2] Cycloaddition To Construct Chiral Cyclopentane Compounds

In recent years,with the continuous development of chemical technology,it has become the goal of chemists to find a simple,mild and pollution-free reaction condition.The storage of sunlight is very rich,and it is green and pollution-free.Photocatalysis can convert solar energy into chemical energy,and then drive the single electron transfer process in chemical reactions to form the active free radicals required in chemical synthesis.Compared with the more demanding reaction conditions in some conventional methods,photocatalyzed reactions have the advantages of mild reaction conditions and high tolerance of functional groups of the substrate.Cycloaddition reactions are a class of highly useful and versatile reactions that are particularly effective for the construction of carbocycles and heterocycles.Two notable examples in this class of reactions are the Diels–Alder reaction and the 1,3-dipolar cycloaddition.Five-membered rings,such as cyclopentanes and the heterocyclic analogs,are another important class of building blocks in organic synthesis.Cyclopropanes are very versatile synthetic building blocks due to ring opening induced by the inherent ring strain.As a structural core,cyclopentane is widely used in many natural products and artificial drugs with biological activity.One of the main approaches to access them is through [3+2] cycloadditions.One particularly attractive strategy for their synthesis is the [3+2] cycloaddition reaction of activated cyclopropanes with olefins.The merging of visible light photocatalysis with [3+2] cycloadditions is primarily achieved by using photocatalysts to manipulate substrates' oxidation states in order to generate the established reactive intermediates in these reactions.This subject uses DPZ(dicyanopyrazine-derived chromophore compound)as a photocatalyst,chiral phosphoric acid as a hydrogen bonding catalyst,visible light induced N-cyclopropyl-3-methoxyaniline ring opening and different types of olefins [3+2] cycloaddition reaction to construct multi-substituted chiral cyclopentane compounds,and achieved high yield and high enantioselectivity.