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
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)+.
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Article; Xu, Yu-Ling; Lin, Hong-Yan; Ruan, Xu; Yang, Sheng-Gang; Hao, Ge-Fei; Yang, Wen-Chao; Yang, Guang-Fu; European Journal of Medicinal Chemistry; vol. 92; (2015); p. 427 – 438;,
Pyrazole – Wikipedia,
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