Potassium Phosphate, Tribasic → 4-(5-(5-(2,5-Dimethyl-4-(oxetan-3-yl)piperazin-1-yl)pyridin-2-ylamino)-1-methyl-6-oxo-1,6-dihydropyridin-3-yl)-2-(1-oxo-3,4,6,7,8,9-hexahydropyrido[3,4-b]indolizin-2(1H)-yl)nicotinaldehyde

Participants

Reaction Steps

A 50-mL single-neck round-bottomed flask equipped with a magnetic stirrer and a reflux condenser was charged with 4-chloro-2-(1-oxo-3,4,6,7,8,9-hexahydropyrido[3,4-b]indolizin-2(1H)-yl)nicotinaldehyde 139a (133 mg, 0.40 mmol), 155a (198 mg, 0.40 mmol), Pd(dppf)Cl2 (17 mg, 0.020 mmol), K3PO4 (254 mg, 1.2 mmol), sodium acetate (98 mg, 1.2 mmol), water (5 drops), and acetonitrile (10 mL). After three cycles of vacuum/argon flush, the mixture was heated at reflux for 3 h. It was then cooled to room temperature and filtered. The filtrate was concentrated under reduced pressure and the resulting residue was purified by silica-gel column chromatography eluting with 30:1 dichloromethane/methanol to afford 155b as white solid (80 mg, 30%). MS-ESI: [M+H]+ 663.3.

Provenance & Evidence