Reference of 5521-55-1, A common heterocyclic compound, 5521-55-1, name is 5-Methylpyrazine-2-carboxylic acid, molecular formula is C6H6N2O2, its 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.
EXAMPLE 2 The reaction is carried out, under nitrogen, in a 1 L*4 neck flask equipped with a mechanical stirrer, water condenser (with gas inlet), and a thermocouple. The reactor is charged with 5-methylpyrazinecarboxylic acid (100 g), ethanol,(300 g) and sulfuric acid (2 g). The contents are refluxed for eight hours at 78 C. The reaction mixture is cooled to ambient temperature and sodium bicarbonate (4 g) is added. About 75% of the solvent is removed under reduced pressure and the resulting suspension is allowed to stand overnight. The solids are filtered and washed with cold methanol (2*80 g). Drying under oven (25 inches of Hg) yielded 101.25 g (84%) of 5-methyl-2-pyrazonecarboxylic acid, ethyl ester.
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.
Reference:
Patent; ISP INVESTMENTS INC.; US2005/239803; (2005); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem