5049-61-6, 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. 5049-61-6 name is Pyrazin-2-amine, 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.
A solution of 2-aminopyrazine 4 (3.81 g, 40.1 mmol) in DMSO (80 mL) and water (2 mL) was stirred at 0 C for 10 min. NBS (16.4 g, 92.2 mmol) was added portionwise to the solution over 50 min, keeping the temperature below 15 C. The reaction mixture was warmed to rt and stirred for 16 h. The solution was poured into ice-water (250 mL) and stirred. The orange solid was collected by filtration and dried. The filtrate was extracted with ethyl acetate (200 mL). The organic layer was washed with 5% aqueous sodium carbonate (50 mL) and water (50 mL), then dried, filtered and concentrated. The combined material was recrystallised from water (200 mL) to give 5 (7.80 g, 77%) as a brown solid. (Found: C, 19.33; H, 1.10; N, 16.68; C4H3N3Br2 requires C, 19.00; H, 1.20; N, 16.62%); deltaH (250 MHz; CDCl3) 5.08 (2H, br s, NH2), 8.07 (1H, s, 6-H); deltaC (125 MHz; CDCl3) 123.7, 123.9, 143.2, 151.9; LC-MS (15 min) m/z 256, 254, 252 (MH+); HPLC tR 4.45 min; purity 98%; (HRMS found: MH+ m/z 251.8776; requires 251.8766).
At the same time, in my other blogs, there are other synthetic methods of this type of compound, Pyrazin-2-amine, and friends who are interested can also refer to it.
Reference:
Article; Caldwell, John J.; Veillard, Nicolas; Collins, Ian; Tetrahedron; vol. 68; 47; (2012); p. 9713 – 9728,16;; ; Article; Caldwell, John J.; Veillard, Nicolas; Collins, Ian; Tetrahedron; vol. 68; 47; (2012); p. 9713 – 9728;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem