Electric Literature of 76537-18-3,Some common heterocyclic compound, 76537-18-3, name is 3-Bromo-5-chloropyrazin-2-amine, molecular formula is C4H3BrClN3, 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.
Into a three-neck flask equipped with a reflux pipe were put 2.48 g of 3-bromo-5-chloropyrazin-2-amine, 2.19 g of 5-chloro-2-methoxyphenylboronic acid, 2.26 g of potassium fluoride, and 43 mL of tetrahydrofuran, and the air in the flask was replaced with nitrogen. The mixture in the flask was degassed by being stirred under reduced pressure, and then 0.44 g of tris(dibenzylideneacetone)dipalladium(0) and 4.0 mL of tri-t-butyl phosphine were added thereto. The mixture was reacted by being stirred at 80 C for 42 hours. After a predetermined time elapsed, the obtained mixture was suction-filtered and the filtrate was concentrated. The obtained residue was purified by silica gel column chromatography using a developing solvent (toluene: ethyl acetate = 10: 1), whereby 1.00 g of 2,8-bis[3-(dibenzothiophen-4-yl)phenyl]benzofuro[2,3- )]pyrazine, which was a target substance, was obtained in a yield of 31 %. A synthesis scheme of Step 1 is shown in (b-1).
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3-Bromo-5-chloropyrazin-2-amine, its application will become more common.
Reference:
Patent; SEMICONDUCTOR ENERGY LABORATORY CO., LTD.; YAMAGUCHI, Tomoya; YOSHIZUMI, Hideko; KIDO, Hiromitsu; TAKAHASHI, Tatsuyoshi; SEO, Satoshi; (162 pag.)WO2018/122664; (2018); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem