Related Products of 402-61-9, As we all know, there are many different methods for the synthesis of a compound, and people can choose the synthesis method that suits their own laboratory according to the actual situation. 402-61-9 name is 5-Methyl-1H-pyrazole-3-carboxylic acid, This compound is widely used in many fields, so it is necessary to find a new synthetic route. The downstream synthesis method of this compound is introduced below.
23.3 g (0.121 mol) of EDC, 16.4 g (0.121 mol) of HOBt and 26.7 g (0.121 mol) of N’-hydroxy-4-(trifluoromethoxy)benzenecarboximide amide were added successively to a solution of 15.3 g (0.121 mol) of 5-methyl-1H-pyrazole-3-carboxylic acid in 600 ml of anhydrous DMF at RT. The mixture was stirred first at RT for 2 h and then at 140 C. for 5 h. After cooling, the mixture was diluted with 2 litres of water and extracted three times with 1 litre of ethyl acetate each time. The combined organic extracts were washed successively with water and saturated sodium chloride solution. After drying over anhydrous magnesium sulphate, the mixture was filtered and the solvent was removed on a rotary evaporator. The crude product obtained was purified by means of filtration with suction over a suction filter filled with silica gel (eluent: cyclohexane/ethyl acetate 5:1?1:1). The product fractions were combined and the solvent was removed on a rotary evaporator to such an extent that the product just started to precipitate out. The precipitation was brought to completion at RT. By filtration and further concentration of the mother liquor, two fractions of solid were obtained, which were combined and dried under a high vacuum. 19.7 g (52% of th.) of the title compound were obtained in total in this way.1H-NMR (400 MHz, CDCl3, delta/ppm): 10.75 (broad, 1H), 8.24 (d, 2H), 7.34 (d, 2H), 6.81 (s, 1H), 2.46 (s, 3H).HPLC (method A): Rt=4.72 min.MS (DCI, NH3): m/z=311 [M+H]+.LC/MS (method F, ESIpos): Rt=1.27 min, m/z=311 [M+H]+.
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 5-Methyl-1H-pyrazole-3-carboxylic acid, and friends who are interested can also refer to it.