Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 5203-77-0, name is 1,3-Dimethyl-1H-pyrazol-5-ol, A new synthetic method of this compound is introduced below., category: pyrazoles-derivatives
2.5 g (0.022 mol) of 1,3-dimethyl-5-hydroxypyrazole,Toluene 30mL into the three bottles,9.0 g of triethylamine (0.09 mol) was added with stirring.Ice bath control temperature of 5-10 ,A toluene solution of 6.3 g (0.022 mol) of 2-methanesulfonyl-4-trifluoromethylbenzoyl chloride was added dropwise,Control the reaction temperature does not exceed 15 ,Drop finished,Remove the ice bath,The reaction was stirred at room temperature for 30 min,TLC detection reaction (ethyl acetate: petroleum ether = 4: 1, GF254, UV color)After the reaction is complete,2-methyl-2-hydroxypropanenitrile (0.2 g)Stirring slowly warming to 45-50 C reaction,TLC detection reaction (ethyl acetate: petroleum ether = 2: 1, GF254, UV color)After the reaction is complete,Was added 9.0 g (0.023 mol) of N-ethanesulfonyl-N- (4-trifluoromethoxyphenyl) bromoacetamide,Control temperature 60-65 C Reaction 8hr,After completion of the reaction, the mixture was cooled and added with 50 mL of water.The organic layer was separated and washed with saturated brine. The solvent was recovered to dryness and the residue was separated by column chromatography to give 7.1 g of the desired product, 48.1%
The synthetic route of 5203-77-0 has been constantly updated, and we look forward to future research findings.