Electric Literature of 5203-77-0, 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. 5203-77-0 name is 1,3-Dimethyl-1H-pyrazol-5-ol, 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.
General procedure: Intermediate 7 (4mmol), dissolved in dry dichloromethane (60mL), and PCl5 (4.2mmol) were added and stirred at room temperature for 1h. The solvent was moved out under reduced pressure to afford acid chloride, the acid chloride was then dissolved in dry CH2Cl2 (60mL), Then 1-methyl-1H-pyrazol-5-ol (4mmol) and Et3N (4.8mmol) were added to the above solution, and stirred for a further 18-24hat room temperature. After adding dichloromethane (30mL), the resultant mixture was washed sequentially with 2N hydrochloric acid (100mL), saturated NaHCO3 and saturated NaCl and dried over Na2SO4. The rest of the solution was evaporated in vacuum and purified by silica gel column chromatography using gradient elution of ethyl acetate/hexane (V:V = 1:2) to obtain the desired intermediate 8 as a write powder (30%-70%). 4.1.10 1-methyl-1H-pyrazol-5-yl3-methyl-2-oxo-1-propyl-2,3-dihydro-1H-benzo[d] imidazole- 5-carboxylate Yield: 45%. m.p. 107-108C. 1H NMR (600MHz, CDCl3) delta 8.01 (dd, J=8.4, 1.2Hz, 1H), 7.77 (d, J=1.2Hz, 1H), 7.48 (d, J=1.8Hz, 1H), 7.10 (d, J=8.4Hz, 1H), 6.20 (d, J=1.8Hz, 1H), 3.92 (t, J=7.2Hz, 2H), 3.80 (s, 3H), 3.51 (s, 3H), 1.91-1.71 (m, 2H), 1.00 (t, J=7.8Hz, 3H). EI-MS (m/z): 314.18 (M)+.
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 1,3-Dimethyl-1H-pyrazol-5-ol, and friends who are interested can also refer to it.