Reference of 912773-21-8,Some common heterocyclic compound, 912773-21-8, name is 2-Bromo-5-chloropyrazine, molecular formula is C4H2BrClN2, 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.
To a suspension of copper (0) powder (244 g, 3877 mmol) in DMSO (5 L) was added ethyl 2-bromo-2,2-difluoroacetate (394 g, 1939 mmol) at RT. The reaction mixture was stirred at RT for 1 h and 2-bromo-5-chloropyrazine (Shanghai Fchemicals Technology Co., Ltd., Shanghai, China) (250 g, 1292 mmol) was added in portion-wise manner. The reaction mixture was stirred at RT for 3 h, and quenched with sat’d solution of ammonium chloride (2.0 L). The mixture was filtered through a celite pad and the filtrate was extracted with ethyl acetate (2 x 2 L). The combined organic layers were dried over Na2SO4 and concentrated under reduced pressure. The residue was purified by silica gel chromatography (0 – 2% ethyl acetate in hexanes) to afford 11a (215 g, 70% yield) as a viscous colorless liquid. 1H NMR (400 MHz, DMSO-d6) _ 9.05 (d, J = 1.4 Hz, 1H), 8.98 (dd, J = 1.4, 0.7 Hz, 1H), 4.39- 4.34 (m, 2H), 1.24 (t, J = 7.1 Hz, 3H).
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2-Bromo-5-chloropyrazine, its application will become more common.
Reference:
Patent; AMGEN INC.; ALLEN, Jennifer R.; BOURBEAU, Matthew P.; BROWN, James A.; CHEN, Ning; FROHN, Michael J.; FU, Zice; LIU, Longbin; LIU, Qingyian; PETTUS, Liping H.; QIAN, Wenyuan; REEVES, Corey; SIEGMUND, Aaron C.; (362 pag.)WO2018/112094; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem