Application of 21279-64-1, These common heterocyclic compound, 21279-64-1, name is 5-Chloropyrazine-2-carboxamide, 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.
3.3 2 -[[2-[4-(2-Methoxyphenyl)piperazin-1-yl]ethyl]amino]pyrazine-5-carboxamide (E)-but-2-enedioate 5.7 g (0.0242 mol) of 2-[4-(2-methoxyphenyl)-piperazin-1-yl]ethanamine, 3.82 g (0. 0242 mol) of 2-chloropyrazine-5-carboxamide, 200 ml of acetonitrile and 3.35 g (0.0242 mol) of sodium carbonate are introduced into a 500 ml round-bottomed flask equipped with a reflux condenser and placed under nitrogen. The mixture is heated at reflux for 22 h, is allowed to cool and the solvent is evaporated under reduced pressure. The residue is purified by chromatography on a column of silica gel, the eluent being a 100/0 to 85/15 dichloromethane/methanol mixture, and the solid obtained is recrystallized from ethyl acetate. 0.96 g (0.0027 mol) of base is obtained. The fumarate is prepared from 0.96 g of base in solution in 50 ml of methanol and from 0.31 g (0.0027 mol) of fumaric acid in solution in 50 ml of methanol. The mixture is concentrated under reduced pressure and the product crystallizes. 0.97 g of white solid is obtained. Melting point: 220-222 C.
Statistics shows that 5-Chloropyrazine-2-carboxamide is playing an increasingly important role. we look forward to future research findings about 21279-64-1.
Reference:
Patent; Synthelabo; US5420130; (1995); A;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem