2 results about "Methylphosphate" patented technology

Compounds of the Formula (I), pharmaceutical compositions comprising compounds of the Formula (I), and their use for treating or preventing cancer: (I)

The invention discloses a preparation method of 3-(difluoromethyl)-1-methyl-pyrazole-4-carboxylic ester and difluoropyrazole acid, which comprises the following steps: reacting 3-(difluoromethyl)-1H-pyrazole-4-carboxylic ester with a first methylation reagent in a methyl phosphate solvent to obtain dimethyl pyrazolium cation salt, and reacting the dimethyl pyrazolium cation salt with a second methylation reagent to obtain the 3-(difluoromethyl)-1-methyl-pyrazole-4-carboxylic ester. And then under the action of a second methylation reagent and a nitrogen-containing reagent, 3-(difluoromethyl)-1-methyl-pyrazole-4-formate is obtained. The preparation method provided by the invention has the advantages of low isomer content, no need of high-temperature and high-vacuum distillation for isomer separation, and simple post-treatment, the methylation reagent and the methyl phosphate solvent can be recycled and repeatedly used for synthesis of the target product difluopyrazole acid, the raw material cost is reduced, and the preparation method has the advantage of environmental protection, and is suitable for industrial production.