38557-72-1, A common heterocyclic compound, 38557-72-1, name is 2-Chloro-3,5-dimethylpyrazine, molecular formula is C6H7ClN2, 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.
To a mixture of 2-chloro-3,5-dimethylpyrazine (2.8 g), 1-Boc-piperazine (3.7 g), palladium (II) acetate (225 mg), 2-(dicyclohexylphosphino)-2′,4′,6′-tri-isopropyl-1,1′-biphenyl (953 mg) and sodium tert-butoxide (2.7 g) was added toluene (40 mL), and the mixture was refluxed for 8 hr. After cooling, the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine, and the solvent was evaporated. The residue was purified by column chromatography (hexane:ethyl acetate) to give 3′,5′-dimethyl-2,3,5,6-tetrahydro[1,2′]bipyrazinyl-4-carboxylic acid tert-butyl ester (5 g). 3′,5′-Dimethyl-2,3,5,6-tetrahydro[1,2′]bipyrazinyl-4-carboxylic acid tert-butyl ester (5 g) was dissolved in chloroform (15 mL), 4N hydrogen chloride/ethyl acetate (15 mL) was added, and the mixture was stirred at room temperature overnight. Ethyl acetate (100 mL) was added, and the mixture was filtered to give the title compound (3.3 g).
The synthetic route of 38557-72-1 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; Mitsubishi Tanabe Pharma Corporation; EP2364975; (2011); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem