Some common heterocyclic compound, 312736-49-5, name is 3,5-Dichloropyrazine-2-carboxylic acid, molecular formula is C5H2Cl2N2O2, 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. Computed Properties of C5H2Cl2N2O2
To a stirred heterogeneous mixture of 3,5-dichloropyrazine-2-carboxylic acid (2.21 g, 11.5 mmol) in anhydrous CH2Cl2 (20 mL), thionyl chloride (7.5 mL, 103 mmol) was added under an atmosphere of nitrogen, followed by anhydrous DMF (30 mg, 0.41 mmol) and the reaction mixture was stirred at room temperature for 1 hour. The reaction mixture was evaporated, dissolved in CH2Cl2 (40 mL) and added dropwise to a solution of 6-nitropyridine-2-sulfonamide (2.32 g, 11.5 mmol) with triethylamine (8.5 mL, 61.0 mmol) at 0 C., stirred overnight (24 h) while allowing to warm to ambient temperature. The reaction mixture was concentrated under reduced pressure. The residue was partitioned between CH2Cl2 (10 mL) and ice-water (200 mL) and acidified with 2 M HCl to pH about 4.0. The resulting solid was filtered, the layers separated and the aqueous layer was extract with CH2Cl2 (3×50 mL). The combined organics were washed sequentially with 1N HCl, saturated sodium chloride solution then dried over sodium sulfate, filtered and evaporated under reduced pressure. The crude material was purified by triturating with dichloromethane (10 mL), filtration and drying to give 3,5-dichloro-N-[(6-nitro-2-pyridyl)sulfonyl]pyrazine-2-carboxamide (2.90 g, 67%) as a white solid. ESI-MS m/z calc. 376.93884. found 378.0 (M+1)+. Retention time: 0.6 minutes.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 312736-49-5, its application will become more common.
Reference:
Patent; VERTEX PHARMACEUTICALS INCORPORATED; Miller, Mark Thomas; Anderson, Corey; Arumugam, Vijayalaksmi; Bear, Brian Richard; Binch, Hayley Marie; Clemens, Jeremy J.; Cleveland, Thomas; Conroy, Erica; Coon, Timothy Richard; Frieman, Bryan A.; Grootenhuis, Peter Diederik Jan; Gross, Raymond Stanley; Hadida-Ruah, Sara Sabina; Haripada, Khatuya; Joshi, Pramod Virupax; Krenitsky, Paul John; Lin, Chun-Chieh; Marelius, Gulin Erdgogan; Melillo, Vito; McCartney, Jason; Nicholls, Georgia McGaughey; Pierre, Fabrice Jean Denis; Silina, Alina; Termin, Andreas P.; Uy, Johnny; Zhou, Jinglan; (590 pag.)US2016/95858; (2016); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem