These common heterocyclic compound, 14508-49-7, name is 2-Chloropyrazine, 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. Quality Control of 2-Chloropyrazine
Under nitrogen protection,To a solution of 2,2,6,6-tetramethylpiperidine (72.8 g, 516.3 mmol)In 500 mL of dry THF solution,N-BuLi (346 mL, 553.7 mmol, 1.6 mol / L THF) was slowly added dropwise at -78 &After completion of the reaction, the reaction mixture was warmed to 0 C and the reaction was continued for 20 min.The reaction mixture was then cooled to -78 C,A solution of 2-chloropyrazine (50 g, 436.3 mmol) in THF (100 mL) was added dropwise to the reaction mixture,30min plus finished,The color of the reaction mixture changed from light yellow to dark brown,The reaction was continued for 10 min at -78-0 degC.DMF (84 ml, 1092 mmol)Was dissolved in THF (50 mL) dropwise dropwise into the reaction mixture,Control the reaction system temperature at -70 ~ -78 ,10min plus finished,The reaction was stirred at -78 C for 2 h.To the reaction mixture was then added MeOH (800 mL)To the reaction mixture, NaBH4 (33 g, 868 mmol) was added portionwise,After the addition, the reaction mixture was allowed to rise to room temperature and stirring continued for 2 h,TLC shows the raw material reaction is complete,The reaction solution was quenched with saturated NH4Cl,DCM (1 L x 3) was extracted three times,The organic phase was washed with water,Anhydrous Na2SO4 fully dried,After vacuum evaporation, the residue was purified by silica gel column (PE / EA = 100/1 to 5/1) to give 60 g of the title compound
The synthetic route of 2-Chloropyrazine has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Chengdu Beite Pharmaceutical Co., Ltd.; Chengdu Hai Borui Pharmaceutical Co., Ltd.; Li Yingfu; Huang Haoxi; Liu Guanfeng; Chen Tonghun; Ren Junfeng; Su Zhonghai; (96 pag.)CN106831787; (2017); A;,
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