Improved process for converting 2- (methylthio) -5- (trifluormethyl) -1,3,4-thiadiazole (tda) to 2- (methylsulfonyl) -5- (trifluormethyl) -1,3,4-thiadiazole (tda sulfone)

摘要

Invention Patent: B "PERFECT PROCESS FOR THE CONVERSION OF 2- (Methylthio) -5- (TRIFLUORMETYL) -1,3,4-THYADIAZOLE (TDA) TO 2- (METHYLSULFONYL) -5- (TRIFLUORMETYL) -1 , 3,4-THYADIAZOLE (TDA SULFONA) "D. The present invention provides a process for making thiadiazole sulfones. In particular, the present process is applied to make 2- (methylsulfonyl) -5- (trifluormethyl) -1,3,4-thiadiazole by applying catalytic oxidation in the presence of a suitable oxidizing agent. The catalyst system applied for the oxidation reaction is a mixture of glacial acetic acid and a tungsten catalyst. The tungsten catalyst is preferably chosen from the group consisting of sodium tungstate, potassium tungstate and tungstic acid.