Reference of 1458-18-0, In the chemical reaction process, reaction time, type of solvent, can easily affect the result of the reaction, thereby determining the yield and properties of the reaction product. An updated downstream synthesis route of 1458-18-0 as follows.
5,6-DICHLORO-3-HYDROXYPYRAZINE-2-CARBOXYLIC ACID (21). Methyl 3-amino-5,6-dichloropyrazine-2-carboxylate (5.0 g, 23 mmol) was stirred in conc. sulfuric acid (140 mL) and cooled to 0 C. Sodium nitrite was added slowly, maintaining the temperature close to 0 C. After an additional 30 minutes at 0 C. the mixture was allowed to warm to ambient temperature and stirred for 3 hours. The mixture was poured into 500 g of ice, resulting in bubbling and foaming. After 30 minutes, the mixture was extracted 3 times with EtOAc. The combined organic extract was dried (MgSO4), filtered and concentrated. The yellow solid which was left was washed with water and air-dried, to leave 5.0 g of a yellow solid, m.p. 114-116 C. whose 13C-NMR spectrum was consistent with the methyl ester of the title compound. This solid (5.0 g) was treated with 1N NaOH (20 mL) and the mixture heated at 90 C. for 1.5 hours. After allowing to cool, the mixture was acidified with conc. HCl, then extracted 3 times with EtOAc. Drying (MgSO4), filtration and concentration afforded 0.48 g of a dark yellow solid, whose 1H-NMR and MS spectra were consistent with the title acid 21.
According to the analysis of related databases, 1458-18-0, the application of this compound in the production field has become more and more popular.
Reference:
Patent; Dow AgroSciences LLC; US6355660; (2002); B1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem