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. 14521-80-3 name is 3-Bromo-1H-pyrazole, 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. 14521-80-3
[00284] To a stirred solution of 5-bromo-1-propylpyridin-2(1H)-one (1.029 g, 4.8 mmol), cesium carbonate (4.655 g, 14.3 mmol), 3-bromopyrazole (0.700 g, 4.8 mmol), in anhydrous DMA (3mL) under argon was added and copper(I) iodide (0.181 g, 1.0 mmol). The mixture was stirred at 120C overnight. After cooling, the mixture was diluted with water and extracted with ethyl acetate (3X20 mL). The combined organics were washed with brine and dried over MgS04. The solvents were dried to evaporation and the residue purified by flash chromatography (0-100% ethyl acetate in hexanes). The pure fractions were collected and dried to give the product as a liquid (320 mg, 24%). LC/MS: [M+l]+ 282.1; 1H MR (300 MHz, CDC13): delta 8.25 (d, J=2.4 Hz, IH), 7.84-7.76 (m, 2H), 7.66 (dd, J=9.9 and 2.4 Hz, IH), 7.56 (dd, J=8.7 and 2.4 Hz, IH) 6.68 (d, J=9.9 Hz, IH), 6.55 (d, J=8.1 Hz, IH), 4.51 (bs, 2H), 3.96 (t, J=7.8 Hz, 2H), 1.87-1.80 (m, 2H), 0.99 (t, J=7.5 Hz, 3H).
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 3-Bromo-1H-pyrazole, and friends who are interested can also refer to it.