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 (500 mg, crude) in DMSO (6 mL) was added DIEA (543 mg, 4.20 mmol), (2S)-2-methylpiperidine (104 mg, 1.05 mmol). The solution was stirred for 6 h at 100° C. Then the reaction was quenched by the addition of water (50 mL). The resulting solution was extracted with ethyl acetate (4×30 mL) and the organic layers were concentrated under vacuum. The residue was purified by a silica gel column with 1%-5% ethyl acetate in petroleum ether to afford methyl 3-[(2S)-2-methylpiperidin-1-yl]-2-oxo-1,2-dihydroquinoxaline-6-carboxylate as a yellow solid (98 mg).

Provenance & Evidence