Synthesis Of Electrochemical Oxidation Of C-H Sulfonation And C-H Amination

Conventional methods for carrying out carbon–hydrogen functionalization are typically conducted at elevated temperatures,and rely on expensive catalysts as well as the use of stoichiometric oxidants.All of these approaches give rise to a significant amount of toxic reagent waste.However,electroorganic synthesis is an attractive technique with huge synthetic potential.since dangerous and toxic redox reagents are replaced by electric current,and the overall energy consumption is reduced.Although the electrochemical step is usually just one part of a multi-step sequence,it constitutes a key process for the generation of a variety of reactive intermediates.In addition,it provides a means whereby unstable or hazardous reagents can be produced in situ and allows reactions to be carried out under mild conditions.Therefore,organic electrochemistry often provides interesting and useful alternatives to conventional synthetic methods and constitutes a useful tool for the organic chemist.And in the laboratory and industry have a very wide range of applications,is a very mature field of organic synthesis.In this paper,a new understanding of electrochemistry,the advantages of electrochemical synthesis and the development of C-S/C-N bonding reactions in electrochemistry are described,and the sulfonation of C-H and the cross-coupling reaction of C-H/N-H by electrochemical methods are described in detail.The main achievements of this paper are as follows:1.An efficient and environmentally benign electrochemical oxidative radical C–H sulfonylation of arenes/heteroarenes was developed in this work.A series of significant diarylsulfones were prepared under mild catalyst-and exogenous-oxidant-free reaction conditions,which efficiently avoid the issues of desulfonylation or over-reduction of sulfonyl groups.2.Under metal catalyst-free and exogenous-oxidant-free conditions,a series of C-3 aminated imidazo[1,2-a]pyridines were synthesized by electrochemical intermolecular oxidative C–H/N–H cross-coupling.Furthermore,by using a catalytic amount of ferrocene as the mediator,electrochemical intramolecular oxidative C–H/N–H cross-coupling for the synthesis of 10H-benzo[4,5]imidazo[1,2-a]indole derivatives has also been accomplished.