Electrocatalytic Reaction Of C-H Bond Activation To Construct Indole Bromide And Carbazole

A large number of C-H bonds generally exist in the chemical structure of organic matter,and the functionalization of carbon-hydrogen bonds is the focus of organic chemistry research.The traditional methods of carbon-hydrogen bond activation and functionalization are carried out at high temperatures,requiring transition metal catalysts and chemical oxidants.These methods will cause environmental problems.Organic electrochemical synthesis is a green and environmentally friendly new technology.It is a cross field of organic chemistry and electrochemistry.It uses electrons instead of chemical oxidants or reducing agents to achieve the oxidation and reduction of organic compounds.It is a green synthesis method.The new technology of organic electrochemical synthesis is mainly used to explore the new methods of organic compounds transfer of electrons on the electrode surface.In the solution,positive and negative ions interact with organic molecules,chemical energy and electrical energy are mutually converted,breaking old bonds and generating new bonds.Organic electrochemical synthesis reduces pollution from the source,so it has become a very practical tool in the field of organic synthetic chemistry.This paper mainly studies the method of constructing C-Br/C-N bond under electrochemical conditions.The dissertation consists of two main parts:The first part of the study is the C-H bond bromination reaction of electrocatalytic oxidation of indole.Under mild reaction conditions,a simple and sustainable method for electrochemical oxidation of bromine negative ions to form bromine positive ions was developed.Using tetrabutylammonium iodide and ammonium bromide as bromine sources and acetonitrile as a solvent,electrolysis was carried out with a constant current of 2 m A,and the yield of 3-bromoindole was 82%.Avoid the use of transition metal catalysts and chemical oxidants during C-H bond bromination.It is worth noting that graphite rods are used as electrode materials.The graphite rods are commercially available and cheap,easy to obtain,and reusable.This method achieves 3-bromoindole synthesis with excellent yield and regioselectivity.The second part of the research is electrochemical C-H bond dehydroamination reaction.This part reports an environmentally friendly method for electrochemical dehydrogenation of C-H bonds,which is widely used to construct carbazole moieties.This method obtains carbazole compounds with a yield of 81%,expands 35 substrates,including 5 new compounds,and obtains 4 alkaloids by deprotection.Preliminary studies indicate that the dehydroamination of synthetic carbazoles is a free radical process.Compared with traditional ion pathways,the absence of transition metals and external oxidants highlights the greenness and sustainability of the method.