1,1'-Carbonyldiimidazole → Ethyl 2-(6-bromo-2-oxo-1,2-dihydropyrido[2,3-d]pyrimidin-3(4H)-yl)acetate
Reaction equation
C1N=CN([C:6](N2C=NC=C2)=[O:7])C=1.[NH2:13][C:14]1[C:19]([CH2:20][NH:21][CH2:22][C:23]([O:25][CH2:26][CH3:27])=[O:24])=[CH:18][C:17]([Br:28])=[CH:16][N:15]=1>O1CCOCC1>[Br:28][C:17]1[CH:16]=[N:15][C:14]2[NH:13][C:6](=[O:7])[N:21]([CH2:22][C:23]([O:25][CH2:26][CH3:27])=[O:24])[CH2:20][C:19]=2[CH:18]=1Participants
4
Procedure
CDI (1.8 g, 114 mmol) was added to a solution of ethyl 2-((2-amino-5-bromopyridin-3-yl)methylamino)acetate (1.1 g, 38.17 mmol) in dioxane (36 mL). The reaction mixture was stirred at reflux for 5 hours and then concentrated to dryness. The residue was partitioned between dichloromethane (40 mL) and water (30 mL). The aqueous phase was separated and extracted with dichloromethane (2×30 mL). The combined organic phases were washed with brine (50 mL), dried over sodium sulfate, filtered and concentrated to dryness. The isolated compound was finally precipitated from a mixture dichloromethane/pentane to give the title product as a yellow solid (670 mg, 56%).