A Study On Three-component Radical Cascade Reaction Of Electron-deficient Olefins As Free Radical Receptors Under Light Induction

Photoinduced catalysis has emerged in recent years as a powerful tool to realize chemical transformations via single electron transfer（SET）processes that would otherwise be inaccessible.In particular,when the radical species generated by the visible light photoinduced approach is involved in well-designed cascade reactions,the formation of multiple chemical bonds and the assembly of structurally complex molecules would be secured in a green and economic manner.This protocol might serve to remodel the way of thinking for the preparation of useful pharmaceuticals and complex natural products.However,the radical addition of olefins in series has been accompanied by relatively harsh conditions such as strong redox agents and（transition）metal catalysts in most of the currently reported studies.This article aims at applying a three-component radical addition tandem reaction of dicyano-substituted electron-deficient olefins serve as free radical acceptors at room temperature and induced by 450 nm light.The main contents of the study are as follows:1)Unactivated olefins,sodium trifluoromethyl sulfinate（Langlois Reagent）, and dicyano-substituted electron-deficient olefins,under the conditions of 450 nm Blue LEDs and room temperature,using DMF as the reaction solvent to complete the trifluoromethyl olefin Difunctionalization reaction.This reaction does not require additional photosensitizers,transition metal catalysts,etc.,and the reaction yield can reach more than90%.2)Unactivated olefins,trimethyl azide silane（TMSN₃）and dicyano-substituted electron-deficient olefins,under the condition of 450 nm Blue LEDs and room temperature,using anhydrous acetonitrile as the reaction solvent to complete the azido-substituted reaction of olefins.The reaction does not require transition metal catalysis,the yield is good,the reaction conditions are mild,and the operation is simple and convenient.