Reference of 87486-34-8,Some common heterocyclic compound, 87486-34-8, name is 3,5-Dibromo-1-methylpyrazin-2(1H)-one, molecular formula is C5H4Br2N2O, 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 109c 5-Bromo-3-(l-cyclopropyl-lH-pyrazol-4-ylamino)-l-methylpyrazin- -one 109cCGIPHARM60WOA 100-mL three-neck round-bottomed flask equipped with a reflux condenser, magnetic stirrer and nitrogen inlet was charged with 109b (378 mg, 3.07 mmol), 3,5- dibromo-l-methylpyrazin-2(lH)-one (906 mg, 3.38 mmol), cesium carbonate (3.00 g, 9.21 mmol), and 1,4-dioxane (45 mL). After bubbling nitrogen through the resulting suspension for 30 min, Xantphos (151 mg, 0.261 mmol) and tris(dibenzylidene-acetone)dipalladium(0) (141 mg, 0.154 mmol) were added, and the reaction mixture was heated at reflux for 3 h. After this time, the mixture was cooled to room tempera-ture and diluted with ethyl acetate (150 mL) and water (30 mL). The organic layer was separated, and the aqueous layer was extracted with ethyl acetate (3 x 45 mL). The combined organic layers were dried over sodium sulfate and concentrated under reduced pressure. The residue was purified by column chromatography (silica, 0percent to 10percent methanol/methylene chloride) to afford a 28percent yield (266 mg) of 109c as an off-white solid: mp 228-230 °C; ]H NMR (300 MHz, DMSO-i3/4) delta 9.90 (s, 1H), 8.06 (s, 1H), 7.69 (s, 1H), 7.21 (s, 1H), 3.70 (m, 1H), 3.41 (s, 3H), 0.96 (m, 4H); MS (ESI+) m/z 310.0 (M+H).
These compound has a wide range of applications. It is believed that with the continuous development of the source of the synthetic route 3,5-Dibromo-1-methylpyrazin-2(1H)-one, its application will become more common.
Reference:
Patent; GILEAD CONNECTICUT, INC.; GENENTECH, INC.; CURRIE, Kevin S.; WANG, Xiaojing; YOUNG, Wendy B.; WO2012/31004; (2012); A1;,
Pyrazine – Wikipedia,
Pyrazine | C4H4N2 – PubChem