Dimethyl Sulfoxide → 4-(7-Methoxy-2-oxoquinoxalin-1(2H)-yl)butanal

Participants

Reaction Steps

A solution of oxalyl chloride (0.171 ml, 1.99 mmol) in dichloromethane (5 ml) was cooled to −78° C., a solution of dimethyl sulfoxide (0.283 ml, 3.99 mmol) in dichloromethane (5 ml) was added dropwise under a stream of argon and the reaction mixture was stirred at the same temperature for 15 minutes. A solution of 1-(4-hydroxybutyl)-7-methoxyquinoxalin-2(1H)-one (198 mg, 0.797 mmol) in dichloromethane (5 ml) was added dropwise and the reaction mixture was further stirred at the same temperature for 1 hour. Triethylamine (0.833 ml, 5.98 mmol) was added thereto, the temperature was raised to room temperature and a saturated ammonium chloride aqueous solution and dichloromethane were added. After stirring, the organic layer was separated, washed with water and saturated sodium chloride solution, dried over magnesium sulfate and the solvent was removed under reduced pressure. The obtained residue was purified by silica gel column chromatography (n-hexane/ethyl acetate) to yield 114 mg (58%) of the title compound in the form of a yellow solid.

Provenance & Evidence