Cesium carbonate → (4-(5-(5-((3R,5S)-3,5-Dimethylmorpholine-4-carbonyl)pyridin-2-ylamino)-1-methyl-6-oxo-1,6-dihydropyridin-3-yl)-2-(1-oxo-3,4,6,7,8,9-hexahydropyrazino[1,2-a]indol-2(1H)-yl)pyridin-3-yl)methyl Acetate

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Reaction Steps

A 25-mL round-bottomed flask equipped with a magnetic stirrer and a reflux condenser was charged with (6-aminopyridin-3-yl)((3R,5S)-3,5-dimethylmorpholino)methanone 320a (120 mg, 0.50 mmol), (4-(5-bromo-1-methyl-6-oxo-1,6-dihydropyridin-3-yl)-2-(1-oxo-3,4,6,7,8,9-hexahydropyrazino[1,2-a]indol-2(1H)-yl)pyridin-3-yl)methyl acetate 217a (262 mg, 0.50 mmol), cesium carbonate (326 mg, 1.0 mmol), and 1,4-dioxane (6 mL). After bubbling nitrogen through the suspension for 10 minutes, Xantphos (58 mg, 0.10 mmol) and tris(dibenzylideneacetone)dipalladium(0) (45 mg, 0.050 mmol) were added. The system was subjected to three cycles of vacuum/nitrogen flush and heated at reflux for 2.5 h. It was then cooled to room temperature and filtered. The solid was washed with dichloromethane (3×10 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 50/1) to afford 322a (200 mg, 59%) as a yellow solid. MS-ESI: [M+H]+ 680.3

Provenance & Evidence