Cesium carbonate → 5-Bromo-3-(5-(3-methoxypropyl)-4,5,6,7-tetrahydropyrazolo[1,5-a]pyrazin-2-yl-amino)-1-methylpyridin-2(1H)-one

Participants

Reaction Conditions

Reaction Steps

A 100-mL single-neck round-bottomed flask equipped with a magnetic stirrer and a reflux condenser was charged with 3,5-dibromo-1-methylpyridin-2(1H)-one (320 mg, 1.2 mmol), 309b (250 mg, 1.2 mmol), tris(dibenzylideneacetone) dipalladium(0) (55 mg, 0.060 mmol), xantphos (70 mg, 0.12 mmol), cesium carbonate (782 mg, 2.4 mmol), and 1,4-dioxane (20 mL). The system was subjected to three cycles of vacuum/argon flush and heated at 100° C. for 5 h. It was then cooled to room temperature and filtered. The solid was washed with dichloromethane (2×10 mL). The combined filtrate was concentrated under reduced pressure. The residue was purified by silica-gel column chromatography eluting with dichloromethane/methanol (80:1 to 30:1) to afford 309c (200 mg, 42%) as yellow solid. MS-ESI: [M+H]+ 396.2

Provenance & Evidence