Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 59489-71-3, name is 2-Amino-5-bromopyrazine, A new synthetic method of this compound is introduced below., name: 2-Amino-5-bromopyrazine
Step 1. A solution of 5-bromopyrazin-2-amine (4.53 g, 26.03 mmol), (4-isopropylsulfonylphenyl)boronic acid (7.125 g, 31.24 mmol) and K3PO4 (11.05 g, 52.06 mmol) in MeCN (90.60 mL)/Water (22.65 mL) was degassed with nitrogen. Pd[P(tBu)3]2. (665.4 mg, 1.302 mmol) was added and the degassing/flushing with nitrogen repeated. The reaction mixture was heated at 60 C. for 4 hours. A further 300 mg catalyst added over the next 30 min and the reaction mixture was stirred for 2 hours at 66 C. to give complete disappearance of the 5-bromopyrazine-2-amine starting material. The reaction mixture was cooled to ambient temperature and diluted with ethylacetate/water. The organic layer was separated and the aqueous layer extracted again with ethylacetate. The combined organic extracts were washed with aq NaCl/NaHCO3, dried over MgSO4, then filtered through a short silica gel column washing through with ethylacetate. The eluant was concentrated in vacuo to about 40 ml volume. The product was filtered off and the product washed with ethylacetate, petrol ether to give 5-(4-(isopropylsulfonyl)phenyl)pyrazin-2-amine a pale yellow powder (5.65 g, 78%). %). 1H NMR (400.0 MHz, DMSO-d6) delta 8.70 (s, 1H), 8.2 (d, 2H), 8.02 (s, 1H), 7.90 (d, 2H), 6.9 (s, 2H), 5.76 (s, 1H), 3.4-3.5 (m, 1H), 1.20 (d, 6H); LC/MS m/z 278.0 [M+H]+.
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; Charrier, Jean-Damien; Storck, Pierre-Henri; Pinder, Joanne; Studley, John R.; US2013/115312; (2013); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem