In the next few decades, the world population will flourish. As the population grows rapidly and people all over the world use more and more resources, all industries must consider their environmental impact. 5521-58-4, name is 5-Methylpyrazin-2-amine belongs to pyrazines compound, it is a common compound, a new synthetic route is introduced below. COA of Formula: C5H7N3
A solution of HBr/CH3CO2H (360 g (260 mL), 1.50 mol, 33% HBr in CH3CO2H) in anhydrous CHCl3 (300 mL) was added over 15 min to a solution of 5-methylpyrazin-2-amine 15 (42 g, 0.38 mmol) in CHCl3 (1 L). The reaction flask was wrapped in aluminum foil and heated to 50 C for 30 min in the dark whereupon a solution of Br2 (68 g, 0.42 mmol) in CHCl3 (500 mL) was added dropwise over 3 h during which time the internal temperature of the reaction never exceeded 55 C. After 18 h at 55 C the solvent was evaporated under reduced pressure. The crude mixture was diluted with water (200 mL) and the pH was adjusted to pH=9 by the addition of solid Na2CO3. The suspension was filtered under vacuum and the filtrate was extracted with EtOAc (1 L×5). The combined organic extracts were concentrated under reduced pressure and purified by flash silica gel chromatography eluting with petroleum ether/EtOAc (5:1?1:1) to give compound 6-bromo-5-methylpyrazin-2-amine 17a (36 g, 50%) as a light orange solid; mp 154-157 C; IR (KBr): 3315, 3188, 1744, 1638, 1575, 1482, 1375, 1308, 1051 cm-1; 1H NMR (400 MHz, CDCl3): delta=7.84 (s, 1H), 4.55 (br s, 2H), 2.52 (s, 3H); 13C NMR (100 MHz, CDCl3): delta=152.2, 141.8, 138.4, 129.2, 22.2; HRMS-ESI: calcd for C5H7BrN3 (M+H)+: 187.9823 and 189.9803; found: 187.9816 and 189.9796. An analytical sample of 3-bromo-5-methylpyrazin-2-amine (17b) was also isolated for spectroscopic analysis; mp 56-57 C. 1H NMR (400 MHz, CDCl3): delta=7.80 (s, 1H), 4.95 (br s, 2H), 2.38 (s, 3H); 13C NMR (100 MHz, CDCl3): delta=150.6, 142.8, 139.9, 125.2, 19.7; HRMS-ESI: calcd for C5H7BrN3 (M+H)+: 187.9823 and 189.9803; found: 187.9817 and 189.9796.
The synthetic route of 5521-58-4 has been constantly updated, and we look forward to future research findings.
Reference:
Article; Harris, Anthony R.; Nason, Deane M.; Collantes, Elizabeth M.; Xu, Wenjian; Chi, Yushi; Wang, Zhihan; Zhang, Bingzhi; Zhang, Qingjian; Gray, David L.; Davoren, Jennifer E.; Tetrahedron; vol. 67; 47; (2011); p. 9063 – 9066;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem