Reference of 52773-23-6, These common heterocyclic compound, 52773-23-6, name is 1-(1,3-Dimethyl-1H-pyrazol-4-yl)ethanone, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
General procedure: To a solution of compound 1 (40 g, 258 mmol) in THF (480 ml)was added Et3N (39.3 ml, 283 mmol) and TMSOTf (51.3 ml,283 mmol) dropwise at 0 C over 1 h. The mixture was stirred atsame temperature for 1 h. To a reaction mixture was added NBS (50.5 g, 283 mmol) at 0 C over 10 min. The mixture was stirred at same temperature for 20 min. After quenching with water, the resulting mixture was extracted with EtOAc. The combined organic extracts were washed with water and brine, dried over MgSO4, filtered,and concentrated. To a solution of crude material in EtOH (600 ml) was added thiourea (19.61 g, 258 mmol) at room temperature.The mixture was refluxed for 1 h. After cooling to room temperature,EtOH was concentrated until about half volume. To are sulting mixture was added sat. NaHCO3 solution (500 ml) and H2O (300 ml) at room temperature. The mixture was stirred at same temperature for 30 min. The resulting solid was filtered and rinsed with H2O. The residue was purified by crystallization (EtOAc/hexane = 1/5) to afford 2 (49.9 g, 91.7%)
The synthetic route of 52773-23-6 has been constantly updated, and we look forward to future research findings.
Reference:
Article; Tsuno, Naoki; Yukimasa, Akira; Yoshida, Osamu; Suzuki, Shinji; Nakai, Hiromi; Ogawa, Tomoyuki; Fujiu, Motohiro; Takaya, Kenji; Nozu, Azusa; Yamaguchi, Hiroki; Matsuda, Hidetoshi; Funaki, Satoko; Yamanada, Natsue; Tanimura, Miki; Nagamatsu, Daiki; Asaki, Toshiyuki; Horita, Narumi; Yamamoto, Miyuki; Hinata, Mikie; Soga, Masahiko; Imai, Masayuki; Morioka, Yasuhide; Kanemasa, Toshiyuki; Sakaguchi, Gaku; Iso, Yasuyoshi; Bioorganic and Medicinal Chemistry; vol. 25; 7; (2017); p. 2177 – 2190;,
Pyrazole – Wikipedia,
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