Related Products of 5049-61-6,Some common heterocyclic compound, 5049-61-6, name is Pyrazin-2-amine, molecular formula is C4H5N3, 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.
[0383] A solution of 2-aminopyrazine (23.86 g, 0.2509 mol) in methylene chloride (420 mL) was cooled to 0 C. and then treated with N-chlorosuccinimide (33.50 g, 0.2509 mol). The reaction mixture was stirred at 0 C. for 24 h. The resulting dark reaction mixture was diluted with water (500 mL) and then concentrated in vacuo to remove methylene chloride. The aqueous layer was continuously extracted with ethyl acetate until product was absence from the aqueous layer as determined by thin layer chromatography. The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 70-230 mesh, 25% ethyl acetate/hexanes) afforded 2-amino-5-chloropyrazine (2.66 g, 8.2%) as a yellow solid: mp 126-128 C.; EI-HRMS m/e calcd for C4H4ClN3 (M+) 129.0094, found 129.0090. [0384] A solution of 2(R)-(3-chloro-4-methanesulfonyl-phenyl)-3-(4-oxo-cyclohexyl)-propionic acid (prepared as in Example 60, 200 mg, 0.56 mmol) and triphenylphosphine (192 mg, 0.73 mmol) in methylene chloride (4.0 mL) cooled to 0 C. was treated with N-bromosuccinimide (128 mg, 0.73 mmol) in small portions. After the complete addition of N-bromosuccinimide, the reaction mixture was allowed to warm to 25 C. over 30 min. The bright orange reaction mixture was then treated with 2-amino-5-chloropyrazine (145 mg, 1.12 mmol) and 2,6-lutidine (0.28 mL, 2.24 mmol). The resulting reaction mixture was stirred at 25 C. for 4 h. The reaction mixture was then diluted with methylene chloride (25 mL) and was successively washed with a 10% aqueous hydrochloric acid solution (1¡Á20 mL), a saturated aqueous sodium bicarbonate solution (1¡Á20 mL) and water (1¡Á20 mL), dried over sodium sulfate, filtered, and concentrated in vacuo. Biotage chromatography (FLASH 40S, Silica, 13/7 hexanes/ethyl acetate to 2/3 hexanes/ethyl acetate) afforded 2(R)-(3-chloro-4-methanesulfonyl-phenyl)-N-(5-chloro-pyrazin-2-yl)-3-(4-oxo-cyclohexyl)-propionamide (137 mg, 52%) as a light yellow foam: [alpha]23589=-27.35 (c=0.49, chloroform); EI-HRMS m/e calcd for C20H21Cl2N3O4S (M+H)+ 470.0703, found 470.0705.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route Pyrazin-2-amine, its application will become more common.
Reference:
Patent; Corbett, Wendy Lea; Grimsby, Joseph Samuel; Haynes, Nancy-Ellen; Kester, Robert Francis; Mahaney, Paige Erin; Racha, Jagdish Kumar; Sarabu, Ramakanth; Wang, Ka; US2003/225283; (2003); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem