Diisopropylethylamine → (S)-methyl 3-(2-methylpiperidin-1-yl)-2-oxo-1,2-dihydroquinoxaline-6-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 3-chloro-2-oxo-1,2-dihydroquinoxaline-6-carboxylate (150 mg, 0.63 mmol) in DMSO (2 mL) was added (S)-2-methylpiperidine (166 mg, 1.7 mmol) and DIEA (217 mg, 1.7 mmol). The resulting solution was stirred for 3 hours at 80° C. and then quenched by the addition of water (250 mL), extracted with dichloromethane (3×100 mL), dried over anhydrous sodium sulfate, and then concentrated under vacuum to give a residue, which was purified via silica gel column chromatography (9% ethyl acetate in petroleum ether) to afford (S)-methyl 3-(2-methylpiperidin-1-yl)-2-oxo-1,2-dihydroquinoxaline-6-carboxylate as white solid (165 mg, 87%).

Provenance & Evidence