Study On Lewis Acid-catalyzed Synthesis Of Polysubstituted 1-sulfonyl-1H-pyrazole

Pyrazole structure unit extensively exists in natural products,drugs and functional materials.Because of its important synthetic research value,the construction of pyrazole has been a hot topic for organic chemistry and pharmaceutical workers.This paper is divided into two parts:In the first chapter,the application of the multi-substituted pyrazole and the recent related synthesis methods are briefly summarized.In the second chapter,we studied the cyclization reaction of toluene sulfonyl hydrazone and 2-(dimethylamine)malonitrile catalyzed by lewis acid.which is highly efficient for the synthesis of 1-sulfonyl-1H-pyrazole.The method is based on the readily available hydrazone compound and 2-(dimethylamine)malonitrile.According to the synthesis of a series of multisubstituted pyrazole compounds has been achieved in the moderate to excellent yields.