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. 24241-18-7 name is 2-Amino-3,5-dibromopyrazine, 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. 24241-18-7
Preparation of compound 36a: 3,5-dibromopyrazin-2-olTo a stirred solution of 3,5-dibromopyrazin-2-amine (30 g, 0.12 mol) in AcOH (300 ml_) was added dropwise cone. H2SO4 (50 ml_) at 15-25 0C. To the resulting solution was then added dropwise a solution of NaNO2 (16.6 g, 0.24 mol) in water (100 ml_) at 10-15 0C during a period of 1.5 h. After the addition, the resulting mixture was stirred at 10-15 0C for 1 h. The reaction mixture was poured into water (3 L) and extracted with EtOAc (1 L x 3). The combined organic layers were washed with saturated NaHCOs (1 L x 3) and brine (1 L) in sequence, dried over Na2SO4 and concentrated in vacuo which gave the title compound 36a as a yellow solid (24 g, 79.4%). 1H NMR (400 MHz, CDCI3): 7.44 (s, 1 H).
At the same time, in my other blogs, there are other synthetic methods of this type of compound, 2-Amino-3,5-dibromopyrazine, and friends who are interested can also refer to it.
Reference:
Patent; PFIZER INC.; NINKOVIC, Sacha; BRAGANZA, John Frederick; COLLINS, Michael Raymond; KATH, John Charles; LI, Hui; RICHTER, Daniel Tyler; WO2010/16005; (2010); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem