In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 5203-77-0 as follows. Application In Synthesis of 1,3-Dimethyl-1H-pyrazol-5-ol
a. 1.22 g (10.9 mmol) of 1,3-dimethyl-5-hydroxypyrazole and 1.1 g (10.9 mmol) of triethylamine are dissolved in 75 ml of acetonitrile and treated at 0 C. with 3.5 g (10.9 mmol) of 2-chloro-4-methylsulfonyl-3-(oxazol-5-yl)-benzoyl chloride in 50 ml of acetonitrile. Stirring is continued at 0 C for 1 hour, and 4.45 g (44 mmol) of triethylamine and 0.61 g (7.2 mmol) of acetocyanohydrin are subsequently added dropwise at room temperature. The solution is stirred at room temperature for 12 hours. For working up, the mixture is first treated with dilute hydrochloric acid and extracted using methyl tert-butyl ether. The ether phase is then extracted using 5% strength potassium carbonate solution. After the aqueous phase has been acidified with hydrochloric acid, the product is extracted from the aqueous phase using ethyl acetate. The ethyl acetate phase is dried using sodium sulfate and concentrated. This gives 1.2 g of crude product which is purified by column chromatography. This gives 0.4 g (27% of theory) of 1,3-dimethyl-4-[2-chloro-4-methylsulfonyl-3-(oxazol-5-yl)-benzoyl]-5-hydroxy-pyrazole, m.p.: 236-241 C. The compound shown in the table which follows is obtained by a similar method:
According to the analysis of related databases, 5203-77-0, the application of this compound in the production field has become more and more popular.