Study On Synthesis Of 1,2,4-triazolo"1,5-a" Pyrimidine-2-sulfonylamide As Herbicide

This dissertation is mainly about the discussion and study of the herbicides of l,2,4-triazolo[l,5-a]pyrimidine-2- sulfonylamide,With the post-cycling route, two N-substituted aryl-5,7-dimethyl -1,2,4-triazolo [1,5-a] pyrimidine-2-sulfonylamide and two N-substituted aryl-5,7-dimethoxyl-1,2,4-triazole[l ,5-a]pyrimidine-2-sulfonylamide compounds were synthesized as examples. At the same time ,the principal reaction conditions were optimized to obtain the better yield, the general way of synthesis of the compounds of l,2,4-triazole[l,5-a]pyrimidine-2-sulfonylamide with post-cycling route was concluded.In this dissertation, the pre-cycling route of this kind of compounds was also studied primarily ,and two important possible intermediates were prepared ,such as 2-benzylthio-5,7-dimethy- l,2,4-triazole[ 1,5-a] pyrimidine (DBMZP) and 2-benzylthio-7-hydroxy-5-methyl-1,2,4-triazole[l,5-a]pyrimidine (BHMZP).In an addition,the synthesis of BDMZP was fully elaborated and optimized,and obtained higher yield.The synthesis of 5-amino-3-mercapto-l,2,4-triazole (AMZ) which is the starting material of the l,2,4-triazole[l,5-a]pyrimidine-2-sulfonylamides was also studied,the yield is higher than the highest yieldever reported.The structure of the final-products were all proved by means of IR,1HNMR, and element analysis.