Electrochemically Enabled Dehydrogenative Annulation Of Alkenes With Diols And Cyclization Cascades Of Nitrogen-Centered Radical

Dehydrogenative annulation reactions are among the most straightforward and efficient approach for the preparation of cyclic structures.However,the applications of this strategy for the synthesis of saturated heterocycles have been rare.In addition,reported dehydrogenative bond-forming reactions commonly employ stoichiometric chemical oxidants,the use of which reduces the sustainability of the synthesis and brings safety and environmental issues.In this thesis,we introduce an organocatalyzed electrochemical dehydrogenative annulation reaction of alkenes with 1,2-and 1,3-diols for the synthesis of 1,4-dioxane and 1,4-dioxepane derivatives.The combination of electrochemistry and redox catalysis using an organic catalyst allows the electrosynthesis to proceed under transition metal-and oxidizing reagent free conditions.In addition,the electrolytic method has a broad substrate scope and is compatible with many common functional groups,providing an efficient and straightforward access to functionalized 1,4-dioxane and 1,4-dioxepane products with diverse substitution patterns.Furthermore,the generation of alkylamide nitrogen-centered radicals and the subsequent cyclization cascades were preliminarily studied on the basis of the arylamide nitrogen-centered radicals carried out by our research group.Through the oxidation of alkylamides directly under metal-free and oxidant-free conditions,without the need of pre-functionalization,the cyclization cascades of alkenes and alkynes to synthesize a series of useful isoquinolinone structural compounds are introduced.The research of this part of work is still undergoing.