Oxycyanation Of Unsaturated Bond And C-H Alkylation Of Heteroarenes

C-C and C-O bonds are two ubiquitous bonds in nature.The construction of such bonds is among the central task of organic chemistry research.In this thesis,C-C or C-O bonds are efficiently constructed via the difunctionalization of carbon-carbon unsaturated bonds with inexpensive copper-catalysis,and also via C-H alkylation of heteroarenes promoted by a Br?nsted acid.There are three chapters in this thesis.Three-component oxycyanation of alkenes: Oxycyanation of unactivated alkenes and styrenes has been accomplished for the first time here.This reaction is enabled by aryl diacyl peroxides and copper-catalysis.Aryl diacyl peroxides serve as the oxygen source and internal oxidants and trimethylsilyl cyanide serves as the cyano source.This reaction is suitable for both terminal and internal alkenes,and features mild conditions,readily available chemical reagents,and good functional group compatibility.Further transformations to amides and tetrazoles have been studied to showcase the potential utilizations of the products.Asymmetric 1,4-oxycyanation of 1,3-enyne to chiral multi-substituted allenes: Catalytic asymmetric 1,4-difunctionalization of conjugated enynes via allenyl radicals is unprecedented.The copper-catalyzed asymmetric 1,4-oxycyanation of 1,3-enynes has been accomplished for the first time here.Aryl diacyl peroxides serve as the oxygen source and trimethylsilyl cyanide serves as the cyano source.The corresponding tetra-substituted chiral allenes were obtained in up to 92% ee.This reaction might proceed via allenyl radical intermediates.C-H alkylation of heteroarenes: A metal-free,Br?nsted acid protocol for Minisci CH alkylation of heteroarenes using alkyl peroxides as the alkylating reagents and internal oxidants simultaneously has been demonstrated.A series of alkyl substituted heteroarenes could be readily achieved by the C-H alkylation with moderate to good yields.A possible mechanistic pathway is proposed,which suggests that the alkyl radical might add to heterocycles,and then rearomatization happens to form the products.