The C-N And C-S Bond Formation Via Electrooxidation Reaction

Carbon-hydrogen(C-H)bond is the most important chemical bond for organic compounds and it is widely found in various components.The construct of C-C and CX(X=N,O,S,P,etc.)bonds from C-H bonds are ideal methods,which shown high atom-and step-economy.How to convert the C-H bond into a C-C bond or a C-X(X=N,O,S,P,etc.)bond with highly efficient and highly selective has been attract much attention in organic synthesis.Recently,the electrochemical anode oxidative reaction has emerged as a powerful and promising strategy for the construction of C-X bonds.As we known,the electrochemical reaction conditions would avoid the pollution problem of using exogenous additives,such as metal-catalyst and strong oxidants.From the first application of the electrochemical to drive nonspontaneous organic reactions was disclosed in 1830 s by Faraday,many groups have developed a variety of methods for the formation of C-N and C-S bonds under electrochemical reaction conditions.This paper reviews the latest developments in this field,and conducts related research work around the electrochemical anodic oxidation of C-H functionalization reactions of anilines.The main research work is as follows:(1)Traditionally,the C-H amination reactions are achieved by transition metal catalyst.However,these methods usually suffer from significant drawbacks and narrow substrate ranges.We have reported a highly para-selective amination of anilines with phenothiazines for producing various functionalized 10-aryl-10H-phenothiazines by anode oxidative strategies.The oxidative amination reaction proceeds electrochemically at room temperature in moderate to good yields(up to 97%),thereby avoiding the use of transition metal catalyst and oxidizing reagents,with excellent functional group tolerance and broad substrate scope.(2)Diarylsulfones,in particular,are found in a wide range of pharmaceutically active molecules and nature products,which exhibit intriguing biological properties.Traditionally,these valuable compounds are synthesized by oxidation of sulfides,Friedel-Crafts sulfonylation of arenes,or transition metal catalysed cross-coupling reactions.However,most of these methods require expensive transition-metal catalysts,stoichiometric amounts of oxidants and/or relatively high temperature.Based on the electrochemical anodic oxidation strategy,we have achieved a C-H sulfonylation reaction of a substituted aniline with a sodium sulfinate as a sulfonylating reagent and an electron as an oxidizing agent.The reaction proceeds efficiently under mild(room temperature),transition-metal-and chemical oxidant-free conditions for producing oor p-amino arylsulfones and diarylsulfones.