Yield:66666-63-5 59.5 g

Reaction Conditions:

with dihydrogen peroxide in N,N-dimethyl-formamide at 15 - 35; for 1 h;Reagent/catalyst;Temperature;Solvent;

Steps:

1-3 Example 1:

Add 420g of N,N-dimethylformamide into a 1000ml clean four-necked bottle, start stirring, add 100.0g of methylmercaptothiadiazole when the temperature is lowered to 15 °C. After stirring and dissolving, 310ml of 30% hydrogen peroxide solution was added dropwise, and the process control temperature did not exceed 35 °C. After observing the precipitation of crystals, the dropwise addition of hydrogen peroxide solution was stopped, and the temperature was controlled at 30-35 °C and stirred for 30min. Then continue to add the remaining hydrogen peroxide solution dropwise, after the dropwise addition, the temperature is controlled at 30-35 °C and stirred for 30 minutes, then the temperature is lowered to 5 °C, the crystals are grown for 30 minutes, and then filtered, and the filter cake is dried under reduced pressure at 60 °C for 3 hours in an oven. After reaching a constant weight, 59.5 g of the target product was obtained. After testing, the purity (HPLC) of the target product of this example, methylmercaptothiadiazole dimer, was 97.9%. The target product prepared in this example was detected by MS and NMR, and it was confirmed that its structure was an impurity of the methylmercaptothiadiazole dimer of the present invention.

References:

CN114478433,2022,A Location in patent:Paragraph 0023-0030