摘要:
The present invention provides a process for making 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole. The process includes the steps of reacting methyldithiocarbazinate with trifluoroacetic acid to form a mixture of 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole and 2,5-bis-(methylthio)-1,3,4-thiadiazole and selectively removing the 2,5-bis-(methylthio)-1,3,4-thiadiazole by acidifying the mixture.
摘要:
The present invention provides a process for making 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole. The process includes the steps of reacting methyidithiocarbazinate with trifluoroacetic acid, in the absence of phosphorus trichloride, to form a mixture of 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole and 2,5-bis-(methylthio)-1,3,4-thiadiazole. Further, the process of the present invention includes selectively removing the 2,5-bis-(methylthio)-1,3,4-thiadiazole by acidifying the reaction mixture, and then separating the aqueous and organic phases.
摘要:
The present invention provides a process of making 2-(methylthio)-5-(trifluoromethyl)-1,3,4-thiadiazole. The process includes the steps of (a) reacting methyldithiocarbazinate with a molar excess of trifluoroacetic acid; and (b) removing the water and excess trifluoroacetic acid. Water and excess trifluoroacetic acid are preferably removed via distillation.
摘要:
Disclosed herein is an improved process for preparing a thiophosphoryl chloride comprising reacting sulfur with a phosphorous trichloride, the improvement comprising a catalytic amount of a tertiary amine catalyst.
摘要:
Disclosed herein is an aqueous process for preparing high yields of methyl dithiocarbazinate by reacting carbon disulfide and hydrazine in an effective ratio, in an aqueous medium to form hydrazinium dithiocarbazinate salt followed by methylating the hydrazinium dithiocarbazinate with methyl bromide.
摘要:
The invention is directed to a process for producing a stable, low odor S,S,S-tributylphosphorotrithioate having a level of dibutyl disulfide of 0.3% by weight or less. The process broadly includes the steps of a) reacting S,S,S-tributylphosphorotrithioite with an oxidizing agent to produce a crude S,S,S-tributylphosphorotrithioate, b) treating the crude product with sodium bisulfite to decompose any excess oxidizing agent, c) adding a caustic solution having a caustic concentration of from 25 to 50% by weight directly to the reaction mixture of step b), the addition of said caustic solution being stopped once the total caustic concentration is less than 10% by weight and once the pH is constant, and d) phase separating S,S,S-tributylphosphorotrithioate from the mixture of step c).
摘要:
Disclosed herein is a process for preparing a phosphorodichloridodithioate comprising reacting a mercaptan with a phosphorus trichloride and sulfur in the presence of an amine catalyst.
摘要:
Disclosed herein is a process for preparing high yields of methyl dithiocarbazinate by reacting carbon disulfide, hydrazine and a base in an aqueous medium, in an effective ratio to form a dithiocarbazinate salt followed by methylating the dithiocarbazinate salt with methyl bromide.
摘要:
Substituted 4-amino-1,2,4-triazine-5-ones are purified to remove unwanted N-isomers by maintaining the crude product at a temperature of from about 55.degree. C. to about 70.degree. C. in the presence of a hydroxide, preferably an alkali metal hydroxide for at least 0.5 hour.
摘要:
The present invention provides a process for making sulfoxides from sulfides. The process includes the step of selectively oxidizing a sulfide utilizing a perborate or a percarbonate as an oxidizing agent.