Research On Functionalization Reaction Of Carboxylic Acids

As two important organic molecular skeletons,aryl amines and sulfur-containing carboxylic acid esters play significant roles in both medical and functional materials.Thus,the development of simple,efficient,and green sustainable methods for the synthesis of aryl amines and sulfur-containing carboxylic acid esters has been a hot research topic in synthetic chemistry.Carboxylic acids are widely found in nature,which are readily available and stable compounds.Carboxyl groups are a class of weakly coordinating groups that can direct group to ortho position.In addition,the carboxyl group can also be removed through decarboxylation with the liberation of CO₂.Therefore,both the carboxyl group-directed ortho-C-H bond functionalization and decarboxylation functionalization are effective methods to construct carbon-carbon or carbon-heteroatom bonds.In view of limitation of previously reported functionalization of carboxylic acids（esterification,amidation,carbonylation,decarboxylation,etc.）,such as the use of noble metals as catalyst,harsh reaction conditions,and limited substrate scope.It’s desired to develop the formation carbon-carbon or carbon-heteroatom bond with carboxylic acids as coupling partner under cheap metal catalysis or metal-free conditions.The content in the thesis mainly includes the following parts:1)Low-cost Cu-promoted the decarboxylative amination of aryl carboxylic acids with formamide,urea and N,N-dimethylformamide to prepare corresponding primary,secondary and tertiary amines under oxygen conditions;2)Facile synthesis of methylthiomethyl esters through Pummerer-type rearrangement of carboxylic acids and DMSO under metal-free conditions.