Reference of 25710-18-3,Some common heterocyclic compound, 25710-18-3, name is 2,3-Dichloropyrido[2,3-b]pyrazine, molecular formula is C7H3Cl2N3, 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.
A mixture of 2,3-dichloropyrido[2,3-b]pyrazine (Intermediate F step 2) (5 g, 25 mmol), p- tolylboronic acid (4.08 g, 30.0 mmol), tricyclohexylphosphine (1 .682 g, 6.00 mmol), and cesium carbonate (16.29 g, 50.0 mmol) in dry dioxane (60ml) was degassed by bubbling nitrogen through (x3). Tris(dibenzylideneacetone)dipalladium (0) (2.289 g, 2.5 mmol) was added and the reaction mixture was degassed by bubbling nitrogen through (x3). The resulting mixture was stirred at 70 ¡ãC for 16 hours and at room temperature for 2 days. The mixture was diluted with water and EtOAc and filtered through Celite.(R).(filter material). The phases were separated and the aqueous extracted with EtOAc The combined organic extracts were washed with brine, dried over MgS04 and concentrated in vacuo. The crude product was purified bychromatography on silica eluting with 0-2percent THF/DCM to give a mixture of the mono and bis arylated products. The materials were re-purified by chromatography on silica eluting with 0-2percent THF/DCM] to afford the title compound;LCMS; Rt 1 .13 mins MS m/z 256/258 [M+H]+ Method 2minl_C_v003
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 2,3-Dichloropyrido[2,3-b]pyrazine, its application will become more common.
Reference:
Patent; NOVARTIS AG; CHARLTON, Steven, John; LEBLANC, Catherine; MCKEOWN, Stephen, Carl; WO2012/7539; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem