Related Products of 28643-16-5, These common heterocyclic compound, 28643-16-5, name is Methyl 3-amino-5-chloropyrazine-2-carboxylate, 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.
Acid-5: 3-(di-tert-Butoxycarbonyl-amino)-5-difluoromethyl-pyrazine-2-carboxylic acid; a) 3-Amino-5-vinyl-pyrazine-2-carboxylic acid methyl ester; To a mixture of 161 mg (0.86 mmol) 3-amino-5-chloro-pyrazine-2-carboxylic acid methyl ester (GB 1248146) , 0.352 ml (1.204 mmol) tributyl(vinyl)tin and 102 mg (2.498 mmol) lithium chloride in DMF was added 30.2 mg (0.043 mmol) PdCI2(PPh3)2 and the mixture was heated to 85 C for 2.5 h. After cooling to room temperature water was added and the mixture was extracted with EtOAc, the combined organic layers were washed with water and half saturated aq. NaCI, dried with Na2S04 and evaporated. The residue was purified by chromatography on silica gel (cyclohexane to cyclohexane/EtOAc 1 :9) to provide the title compound as yellow solid.HPLC: 0.71 min; ESIMS [M+H]+ = 179.9;1H-NMR (600 MHz, DMSO-cfe): delta 8.04 (s, 1 H), 7.35 (br. s, 1 H), 6.75 (dd, 1 H), 6.38 (d, 1 H), 5.70 (d, 1 H), 3.84 (s, 3H).
The synthetic route of 28643-16-5 has been constantly updated, and we look forward to future research findings.
Reference:
Patent; NOVARTIS AG; HURTH, Konstanze; LUEOEND, Rainer Martin; MACHAUER, Rainer; NEUMANN, Ulf; RUEEGER, Heinrich; SCHAEFER, Michael; TINTELNOT-BLOMLEY, Marina; VEENSTRA, Siem Jacob; VOEGTLE, Markus; WO2012/95463; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem