Study On Direct Amidation Of Carboxylic Acids With Nitroarenes

N-arylamides are an important class of organic compounds that are widely found in pharmaceutical and pesticide chemicals.Consequently,the development of new reactions for the rapid and efficient preparations of densely functionalized amides is particularly significant and could offer valuable applications.In recent years,the reduction coupling reaction of using cheap and easily available nitroarenes instead of amines as the source of amino groups has attracted widespread attention.In this thesis,we studied the direct reductive coupling reaction based on nitroarenes and carboxylic acids,which could offer a straightforward and expedient synthesis of a broad array of N-arylamide compounds.In this reaction,the carboxylic acid was initially activated in situ under the activation by triphenylphosphine and iodine,followed by addition of reductive nitroarenes in situ and performs one-pot amidation conversion with the activated carboxylic acid.The corresponding intermediate did not need to be isolated during the reaction.The reaction is simple and concise,giving a wide range of N-aryl amides in good to excellent yields（up to 95%）.51 N-arylamide compounds have been synthesized,including three N-arylamide-based drug analogs and pesticide active ingredients.All the compounds prepared were characterized by ¹H NMR and ¹³C NMR spectroscopies,and new compounds were further characterized by high-resolution mass spectrometry（HRMS）.Moreover,the plausible reaction mechanism was proposed based on control experiments.