Cesium carbonate → 2-Chloro-8-[4-(dimethyl-phosphinoyl)-phenyl]-[1,2,4]triazolo[1,5-a]pyridine

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Reaktionsschritte

198 b) To an oven dried tube was added 8-(4-bromo-phenyl)-2-chloro-[1,2,4]triazolo[1,5-a]pyridine (0.90 g, 2.9 mmol), methylphosphinoylmethane (0.24 g, 3.1 mmol) (prepared as described in WO2005/009348), palladium acetate (13.5 mg, 0.0601 mmol), 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene (36.0 mg, 0.0622 mmol), cesium carbonate (1422.0 mg, 4.3644 mmol) and 1,4-dioxane (9 mL). The tube was evacuated, carefully, and backflushed with nitrogen. The tube was sealed and heated at 90° C. for 24 hours then cooled to room temperature, diluted with dichloromethane (30 mL), filtered through a plug of diatomaceous earth and evaporated. The residue was purified via chromatography using an ISCO automated purification apparatus (silica gel column 40 g and 0%→7% dichloromethane:methanol). 2-Chloro-8-[4-(dimethyl-phosphinoyl)-phenyl]-[1,2,4]triazolo[1,5-a]pyridine was isolated as a white solid (0.303 g, 34%). MP=220-223° C. 1H NMR (400 MHz, CDCl3, δ, ppm): 8.55 (d, J=6.9 Hz, 1H), 8.11 (d, J=7.7 Hz, 2H), 7.94-7.86 (m, 2H), 7.77 (t, J=7.4 Hz, 1H), 7.21 (t, J=6.9 Hz, 1H), 1.80 (s, 3H), 1.77 (s, 3H). MS=306, 308 (MH)+.

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