Some common heterocyclic compound, 55557-52-3, name is 3-Chloropyrazine-2-carbonitrile, molecular formula is C5H2ClN3, 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. 55557-52-3
Step 1. Preparation of N-(3-cyano-pyrazin-2-yl)-N-methyl-methane sulfonamide (B2-1): A solution of chloropyrazine-2-carbonitrile (4.2 g, 30.21 mmol) in acetonitrile (200 mL) at 25 C. was treated sequentially with Cs2CO3 (13.7831 g, 42.293 mmol) and N-methyl-methane sulfonamide (3.957 g, 36.25 mmol). The mixture was then heated to 80 C. After about 20 hours the mixture was cooled to 25 and filtered. The solids were washed with EtOAc (3*25 mL) and the combined filtrates were concentrated. The resultant residue was treated with water (50 mL) and extracted with EtOAc (3*75 mL). The combined organic layers were washed with water (50 mL), brine, dried over anhydrous sodium sulfate and concentrated. The resultant residue was purified by column chromatography (100-200 mesh silica gel; 40% EtOAc in petroleum ether as eluding solvent) to provide B2-1 as a pale brown liquid. Yield: 4.7 g, 73.43%). 1H NMR (CDCl3) delta: 8.92 (d, 2H), 3.4 (s, 3H) and 3.25 (s, 3H). Mass: (M+1) 213 calculated for C7H8N4O2S. (Note: The product contained unreacted N-methanesulfonamide as an impurity.
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 55557-52-3, its application will become more common.
Reference:
Patent; Pfizer Inc.; US2009/54395; (2009); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem